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How to Un-install a Plugin From Eclipse / STS?
It is easy to do - a few button clicks (generally) - but the button location is damn unintuitive. So, this is what you have got to do Go to "Help" menu item. Click on "About ..." button (why on earth should I click that when I am trying to un-install a plugin. By the way, the menu item just above "About ..." is "Install New Software ...". Would it have been too much pain to have a "Manage plugins" and / or "Un-install plugins" right underneath it?) A form opens up. At the bottom of it there is button "Installation details". Click that. (Again, why on earth would anyone think "Installation details" would have anything to do with un-installing stuff. I would have expected only a static display of stuff that are already installed.) Another multi tabbed form opens up (Anyone keeping count of the number of windows opened already. This is the 3rd window by now, including the parent editor window) which shows all the installed plugins. If you select any of the installed plugins, a button to "uninstall" becomes available. Click that and you should be able to un-install and after a restart everything should be fine. My interest in software and IT has always been much more than a 9 to 5 job (and I am sure there is a huge population that it holds equally true for). I have always wanted software to be efficient and beautiful apart from doing it's job. However, it took an excellent session on usability (which I joined only with casual curiosity but left with renewed interest in the subject and admiration for David Travis who delivered the course) to get me to start looking at all software with an "user's" perspective. And I was surprised with what I found and how it changed my coding. I have been using Eclipse and STS for years now (nearing a decade now) and I absolutely love these software. However when you start looking at them as a "user" and not only as a developer, there are quite a few usability opportunities of improvement that meets the eye. This article - apart from helping folks looking to un-install plugins in Eclipse - is also intended at folks who design Eclipse - just a humble request to consider this also as a usability improvement.
January 1, 2013
by Partha Bhattacharjee
· 16,361 Views
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How to Change the Default Webapp Deployment Location of Tomcat in Eclipse
When you deploy your Java web application to the Apache Tomcat server, via Eclipse, by default the web app will be deployed under {YOUR_ECLIPSE_WORKSPACE}\.metadata\.plugins\org.eclipse.wst.server.core\tmp{a-number}\wtpwebapps. Suppose if you want to deploy your web app to a location that is easily navigable, follow these steps. First make sure you have removed all the web apps that are currently added to your server instance (In servers view, right click on the server name and then Add and Remove). And then double click on the server instance in servers view which will open up that server’s configuration page. On that page, see under Server Locations and select either the option Use Tomcat Installation to deploy the web app under the directory where the Tomcat server is installed or Use custom location to manually specify. Save, Re-add the web application and then Publish. Now the deployed web app will be under the directory of your choice.
December 15, 2012
by Veera Sundar
· 26,420 Views
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Spring Integration Mock SftpServer Example
In this example I will show how to test Spring Integration flow using Mock SftpServer.
December 14, 2012
by Krishna Prasad
· 47,764 Views · 3 Likes
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Using Spring FakeFtpServer to JUnit test a Spring Integration Flow
for people in hurry, get the latest code and the steps in github . to run the junit test, run “mvn test” and understand the test flow. introduction: fakeftpserver in this spring integration fakeftpserver example, i will demonstrate using spring fakeftpserver to junit test a spring integration flow. this is an interesting topic, and there are few articles on unit testing file transfers , which gives some insight on this topic. in this blog, we will test a spring integration flow which checks for a list of files, apply a splitter to separate each file and start downloading them into a local location. once the download is complete, it will delete the files on the ftp server. in my next blog, i will show how to do junit testing of spring integration flow with sftp server. spring integration flow spring integration fakeftpserver example in order to use fakeftpserver we need to have maven dependency as below, org.mockftpserver mockftpserver 2.3 test the first step to this is to create a fakeftpserver before every test runs as below, @before public void setup() throws exception { fakeftpserver = new fakeftpserver(); fakeftpserver.setservercontrolport(9999); // use any free port filesystem filesystem = new unixfakefilesystem(); filesystem.add(new fileentry(file, contents)); fakeftpserver.setfilesystem(filesystem); useraccount useraccount = new useraccount("user", "password", home_dir); fakeftpserver.adduseraccount(useraccount); fakeftpserver.start(); } @after public void teardown() throws exception { fakeftpserver.stop(); } finally run the junit test case as seen below, @autowired private filedownloadutil downloadutil; @test public void testftpdownload() throws exception { file file = new file("src/test/resources/output"); delete(file); ftpclient client = new ftpclient(); client.connect("localhost", 9999); client.login("user", "password"); string files[] = client.listnames("/dir"); client.help(); logger.debug("before delete" + files[0]); assertequals(1, files.length); downloadutil.downloadfilesfromremotedirectory(); logger.debug("after delete"); files = client.listnames("/dir"); client.help(); assertequals(0, files.length); assertequals(1, file.list().length); } i hope this blog helped.
December 13, 2012
by Krishna Prasad
· 17,632 Views
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Drag and Drop with AngularJS using jQuery UI
Use jQuery's UI To drag and drop within a single or multiple lists in AngularJS.
December 12, 2012
by Jos Dirksen
· 72,753 Views · 1 Like
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Using JUnit Theories with Spring and Mockito
What is a Theory? Functionally, a theory is an alternative to JUnit's parameterized tests. Semantically, a theory encapsulates the tester's understanding of an object's universal behavior. That is, whatever it is that a theory asserts, it is expected to be true for all data. Theories should be especially useful for finding bugs in edge cases. Contrast this with a typical unit test, which asserts that a specific data point will have a specific outcome, and only asserts that. (For this reason, typical unit tests are sometimes called example-based tests to contrast them with theories.) This is very nice in theory, but... A @Theory needs a special JUnit runner (Theories.class). So if you want to use Spring and/or Mockito together with theories, you have a problem. All of these features need a different runner and you can only use one on each test class. The solution For Mockito is easy. Instead of using the @Mock annotiation, you can use the static createMock method. One problem solved. For Spring is a little bit trickier. First of all, you have to use @ContextConfiguration to declare the XML with the bean definitions that you need. But the trickiest part is that you have to tell Spring how to do the autowiring without using its own runner. This can be accomplish adding this line to the @Before method: new TestContextManager(getClass()).prepareTestInstance(this); Basic Usage Example package org.mackenzine.theories; import static org.junit.Assert.assertEquals; import static org.junit.Assert.assertNotNull; import static org.mockito.Mockito.when; import java.util.Date; import org.junit.Before; import org.junit.experimental.theories.DataPoints; import org.junit.experimental.theories.Theories; import org.junit.experimental.theories.Theory; import org.junit.runner.RunWith; import org.mockito.Mockito; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.test.context.ContextConfiguration; import org.springframework.test.context.TestContextManager; @RunWith(Theories.class) @ContextConfiguration("classpath:parser.xml") public class QuoteTheoriesTest { private static String deleteMessage = "deleteMessage"; private static String updateMessage = "updateMessage"; private QuoteFactory factory; private final Event event = Mockito.mock(Event.class); private final Contract contract = Mockito.mock(Contract.class); private final Commodity commodity = Mockito.mock(Commodity.class); @Autowired private Parser parser; @Before public void setUp() throws Exception { factory = new QuoteFactory(); new TestContextManager(getClass()).prepareTestInstance(this); } @DataPoints public static String[] getEventTypes() { return new String[] { updateMessage, deleteMessage }; } @Theory public void shouldCreateQuote(final String message) throws Exception { Date now = new Date(); when(event.getParsedMessage()).thenReturn(parser.parse(message)); when(event.getContract()).thenReturn(contract); when(event.getTradeDate()).thenReturn(now); when(contract.getExternalCode()).thenReturn("externalCode"); when(contract.getCommodity()).thenReturn(commodity); when(commodity.getCommodityCode()).thenReturn("code"); Quote quote = factory.createQuote(event); assertNotNull(quote); assertEquals("code", quote.getCommodityCode()); assertEquals(now, quote.getTradeDate()); } } Sources Definition of Theories: https://blogs.oracle.com/jacobc/entry/junit_theories Original Idea for Parameterized Tests: http://stackoverflow.com/questions/8974977/spring-parameterized-theories-junit-tests Thread on SpringSource: http://forum.springsource.org/showthread.php?78929-Is-Theory-supported Open Issue in SpringSource for Parameterized Tests (not for Theories): https://jira.springsource.org/browse/SPR-5292
December 11, 2012
by Lucas Godoy
· 17,651 Views · 1 Like
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Configuring IIS methods for ASP.NET Web API on Windows Azure Websites
That’s a pretty long title, I agree. When working on my implementation of RFC2324, also known as the HyperText Coffee Pot Control Protocol, I’ve been struggling with something that you will struggle with as well in your ASP.NET Web API’s: supporting additional HTTP methods like HEAD, PATCH or PROPFIND. ASP.NET Web API has no issue with those, but when hosting them on IIS you’ll find yourself in Yellow-screen-of-death heaven. The reason why IIS blocks these methods (or fails to route them to ASP.NET) is because it may happen that your IIS installation has some configuration leftovers from another API: WebDAV. WebDAV allows you to work with a virtual filesystem (and others) using a HTTP API. IIS of course supports this (because flagship product “SharePoint” uses it, probably) and gets in the way of your API. Bottom line of the story: if you need those methods or want to provide your own HTTP methods, here’s the bit of configuration to add to your Web.config file: Here’s what each part does: Under modules, the WebDAVModule is being removed. Just to make sure that it’s not going to get in our way ever again. The security/requestFiltering element I’ve added only applies if you want to define your own HTTP methods. So unless you need the XYZ method I’ve defined here, don’t add it to your config. Under handlers, I’m removing the default handlers that route into ASP.NET. Then, I’m adding them again. The important part? The "verb attribute. You can provide a list of comma-separated methods that you want to route into ASP.NET. Again, I’ve added my XYZ methodbut you probably don’t need it. This will work on any IIS server as well as on Windows Azure Websites. It will make your API… happy.
December 11, 2012
by Maarten Balliauw
· 20,727 Views
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Hazelcast Distributed Execution with Spring
The ExecutorService feature had come with Java 5 and is under the java.util.concurrent package. It extends the Executor interface and provides a thread pool functionality to execute asynchronous short tasks. Java Executor Service Types is suggested to look over basic ExecutorService implementation. Also ThreadPoolExecutor is a very useful implementation of ExecutorService ınterface. It extends AbstractExecutorService providing default implementations of ExecutorService execution methods. It provides improved performance when executing large numbers of asynchronous tasks and maintains basic statistics, such as the number of completed tasks. How to develop and monitor Thread Pool Services by using Spring is also suggested to investigate how to develop and monitor Thread Pool Services. So far, we have just talked Undistributed Executor Service implementation. Let us also investigate Distributed Executor Service. Hazelcast Distributed Executor Service feature is a distributed implementation of java.util.concurrent.ExecutorService. It allows to execute business logic in cluster. There are four alternative ways to realize it : 1) The logic can be executed on a specific cluster member which is chosen. 2) The logic can be executed on the member owning the key which is chosen. 3) The logic can be executed on the member Hazelcast will pick. 4) The logic can be executed on all or subset of the cluster members. This article shows how to develop Distributed Executor Service via Hazelcast and Spring. Used Technologies : JDK 1.7.0_09 Spring 3.1.3 Hazelcast 2.4 Maven 3.0.4 STEP 1 : CREATE MAVEN PROJECT A maven project is created as below. (It can be created by using Maven or IDE Plug-in). STEP 2 : LIBRARIES Firstly, Spring dependencies are added to Maven’ s pom.xml 3.1.3.RELEASE UTF-8 org.springframework spring-core ${spring.version} org.springframework spring-context ${spring.version} com.hazelcast hazelcast-all 2.4 log4j log4j 1.2.16 maven-compiler-plugin(Maven Plugin) is used to compile the project with JDK 1.7 org.apache.maven.plugins maven-compiler-plugin 3.0 1.7 1.7 maven-shade-plugin(Maven Plugin) can be used to create runnable-jar org.apache.maven.plugins maven-shade-plugin 2.0 package shade com.onlinetechvision.exe.Application META-INF/spring.handlers META-INF/spring.schemas STEP 3 : CREATE Customer BEAN A new Customer bean is created. This bean will be distributed between two node in OTV cluster. In the following sample, all defined properties(id, name and surname)’ types are String and standart java.io.Serializable interface has been implemented for serializing. If custom or third-party object types are used, com.hazelcast.nio.DataSerializable interface can be implemented for better serialization performance. package com.onlinetechvision.customer; import java.io.Serializable; /** * Customer Bean. * * @author onlinetechvision.com * @since 27 Nov 2012 * @version 1.0.0 * */ public class Customer implements Serializable { private static final long serialVersionUID = 1856862670651243395L; private String id; private String name; private String surname; public String getId() { return id; } public void setId(String id) { this.id = id; } public String getName() { return name; } public void setName(String name) { this.name = name; } public String getSurname() { return surname; } public void setSurname(String surname) { this.surname = surname; } @Override public int hashCode() { final int prime = 31; int result = 1; result = prime * result + ((id == null) ? 0 : id.hashCode()); result = prime * result + ((name == null) ? 0 : name.hashCode()); result = prime * result + ((surname == null) ? 0 : surname.hashCode()); return result; } @Override public boolean equals(Object obj) { if (this == obj) return true; if (obj == null) return false; if (getClass() != obj.getClass()) return false; Customer other = (Customer) obj; if (id == null) { if (other.id != null) return false; } else if (!id.equals(other.id)) return false; if (name == null) { if (other.name != null) return false; } else if (!name.equals(other.name)) return false; if (surname == null) { if (other.surname != null) return false; } else if (!surname.equals(other.surname)) return false; return true; } @Override public String toString() { return "Customer [id=" + id + ", name=" + name + ", surname=" + surname + "]"; } } STEP 4 : CREATE ICacheService INTERFACE A new ICacheService Interface is created for service layer to expose cache functionality. package com.onlinetechvision.cache.srv; import com.hazelcast.core.IMap; import com.onlinetechvision.customer.Customer; /** * A new ICacheService Interface is created for service layer to expose cache functionality. * * @author onlinetechvision.com * @since 27 Nov 2012 * @version 1.0.0 * */ public interface ICacheService { /** * Adds Customer entries to cache * * @param String key * @param Customer customer * */ void addToCache(String key, Customer customer); /** * Deletes Customer entries from cache * * @param String key * */ void deleteFromCache(String key); /** * Gets Customer cache * * @return IMap Coherence named cache */ IMap getCache(); } STEP 5 : CREATE CacheService IMPLEMENTATION CacheService is implementation of ICacheService Interface. package com.onlinetechvision.cache.srv; import com.hazelcast.core.IMap; import com.onlinetechvision.customer.Customer; import com.onlinetechvision.test.listener.CustomerEntryListener; /** * CacheService Class is implementation of ICacheService Interface. * * @author onlinetechvision.com * @since 27 Nov 2012 * @version 1.0.0 * */ public class CacheService implements ICacheService { private IMap customerMap; /** * Constructor of CacheService * * @param IMap customerMap * */ @SuppressWarnings("unchecked") public CacheService(IMap customerMap) { setCustomerMap(customerMap); getCustomerMap().addEntryListener(new CustomerEntryListener(), true); } /** * Adds Customer entries to cache * * @param String key * @param Customer customer * */ @Override public void addToCache(String key, Customer customer) { getCustomerMap().put(key, customer); } /** * Deletes Customer entries from cache * * @param String key * */ @Override public void deleteFromCache(String key) { getCustomerMap().remove(key); } /** * Gets Customer cache * * @return IMap Coherence named cache */ @Override public IMap getCache() { return getCustomerMap(); } public IMap getCustomerMap() { return customerMap; } public void setCustomerMap(IMap customerMap) { this.customerMap = customerMap; } } STEP 6 : CREATE IDistributedExecutorService INTERFACE A new IDistributedExecutorService Interface is created for service layer to expose distributed execution functionality. package com.onlinetechvision.executor.srv; import java.util.Collection; import java.util.Set; import java.util.concurrent.Callable; import java.util.concurrent.ExecutionException; import com.hazelcast.core.Member; /** * A new IDistributedExecutorService Interface is created for service layer to expose distributed execution functionality. * * @author onlinetechvision.com * @since 27 Nov 2012 * @version 1.0.0 * */ public interface IDistributedExecutorService { /** * Executes the callable object on stated member * * @param Callable callable * @param Member member * @throws InterruptedException * @throws ExecutionException * */ String executeOnStatedMember(Callable callable, Member member) throws InterruptedException, ExecutionException; /** * Executes the callable object on member owning the key * * @param Callable callable * @param Object key * @throws InterruptedException * @throws ExecutionException * */ String executeOnTheMemberOwningTheKey(Callable callable, Object key) throws InterruptedException, ExecutionException; /** * Executes the callable object on any member * * @param Callable callable * @throws InterruptedException * @throws ExecutionException * */ String executeOnAnyMember(Callable callable) throws InterruptedException, ExecutionException; /** * Executes the callable object on all members * * @param Callable callable * @param Set all members * @throws InterruptedException * @throws ExecutionException * */ Collection executeOnMembers(Callable callable, Set members) throws InterruptedException, ExecutionException; } STEP 7 : CREATE DistributedExecutorService IMPLEMENTATION DistributedExecutorService is implementation of IDistributedExecutorService Interface. package com.onlinetechvision.executor.srv; import java.util.Collection; import java.util.Set; import java.util.concurrent.Callable; import java.util.concurrent.ExecutionException; import java.util.concurrent.ExecutorService; import java.util.concurrent.Future; import java.util.concurrent.FutureTask; import org.apache.log4j.Logger; import com.hazelcast.core.DistributedTask; import com.hazelcast.core.Member; import com.hazelcast.core.MultiTask; /** * DistributedExecutorService Class is implementation of IDistributedExecutorService Interface. * * @author onlinetechvision.com * @since 27 Nov 2012 * @version 1.0.0 * */ public class DistributedExecutorService implements IDistributedExecutorService { private static final Logger logger = Logger.getLogger(DistributedExecutorService.class); private ExecutorService hazelcastDistributedExecutorService; /** * Executes the callable object on stated member * * @param Callable callable * @param Member member * @throws InterruptedException * @throws ExecutionException * */ @SuppressWarnings("unchecked") public String executeOnStatedMember(Callable callable, Member member) throws InterruptedException, ExecutionException { logger.debug("Method executeOnStatedMember is called..."); ExecutorService executorService = getHazelcastDistributedExecutorService(); FutureTask task = (FutureTask) executorService.submit( new DistributedTask(callable, member)); String result = task.get(); logger.debug("Result of method executeOnStatedMember is : " + result); return result; } /** * Executes the callable object on member owning the key * * @param Callable callable * @param Object key * @throws InterruptedException * @throws ExecutionException * */ @SuppressWarnings("unchecked") public String executeOnTheMemberOwningTheKey(Callable callable, Object key) throws InterruptedException, ExecutionException { logger.debug("Method executeOnTheMemberOwningTheKey is called..."); ExecutorService executorService = getHazelcastDistributedExecutorService(); FutureTask task = (FutureTask) executorService.submit(new DistributedTask(callable, key)); String result = task.get(); logger.debug("Result of method executeOnTheMemberOwningTheKey is : " + result); return result; } /** * Executes the callable object on any member * * @param Callable callable * @throws InterruptedException * @throws ExecutionException * */ public String executeOnAnyMember(Callable callable) throws InterruptedException, ExecutionException { logger.debug("Method executeOnAnyMember is called..."); ExecutorService executorService = getHazelcastDistributedExecutorService(); Future task = executorService.submit(callable); String result = task.get(); logger.debug("Result of method executeOnAnyMember is : " + result); return result; } /** * Executes the callable object on all members * * @param Callable callable * @param Set all members * @throws InterruptedException * @throws ExecutionException * */ public Collection executeOnMembers(Callable callable, Set members) throws ExecutionException, InterruptedException { logger.debug("Method executeOnMembers is called..."); MultiTask task = new MultiTask(callable, members); ExecutorService executorService = getHazelcastDistributedExecutorService(); executorService.execute(task); Collection results = task.get(); logger.debug("Result of method executeOnMembers is : " + results.toString()); return results; } public ExecutorService getHazelcastDistributedExecutorService() { return hazelcastDistributedExecutorService; } public void setHazelcastDistributedExecutorService(ExecutorService hazelcastDistributedExecutorService) { this.hazelcastDistributedExecutorService = hazelcastDistributedExecutorService; } } STEP 8 : CREATE TestCallable CLASS TestCallable Class shows business logic to be executed. TestCallable task for first member of the cluster : package com.onlinetechvision.task; import java.io.Serializable; import java.util.concurrent.Callable; /** * TestCallable Class shows business logic to be executed. * * @author onlinetechvision.com * @since 27 Nov 2012 * @version 1.0.0 * */ public class TestCallable implements Callable, Serializable{ private static final long serialVersionUID = -1839169907337151877L; /** * Computes a result, or throws an exception if unable to do so. * * @return String computed result * @throws Exception if unable to compute a result */ public String call() throws Exception { return "First Member' s TestCallable Task is called..."; } } TestCallable task for second member of the cluster : package com.onlinetechvision.task; import java.io.Serializable; import java.util.concurrent.Callable; /** * TestCallable Class shows business logic to be executed. * * @author onlinetechvision.com * @since 27 Nov 2012 * @version 1.0.0 * */ public class TestCallable implements Callable, Serializable{ private static final long serialVersionUID = -1839169907337151877L; /** * Computes a result, or throws an exception if unable to do so. * * @return String computed result * @throws Exception if unable to compute a result */ public String call() throws Exception { return "Second Member' s TestCallable Task is called..."; } } STEP 9 : CREATE AnotherAvailableMemberNotFoundException CLASS AnotherAvailableMemberNotFoundException is thrown when another available member is not found. To avoid this exception, first node should be started before the second node. package com.onlinetechvision.exception; /** * AnotherAvailableMemberNotFoundException is thrown when another available member is not found. * To avoid this exception, first node should be started before the second node. * * @author onlinetechvision.com * @since 27 Nov 2012 * @version 1.0.0 * */ public class AnotherAvailableMemberNotFoundException extends Exception { private static final long serialVersionUID = -3954360266393077645L; /** * Constructor of AnotherAvailableMemberNotFoundException * * @param String Exception message * */ public AnotherAvailableMemberNotFoundException(String message) { super(message); } } STEP 10 : CREATE CustomerEntryListener CLASS CustomerEntryListener Class listens entry changes on named cache object. package com.onlinetechvision.test.listener; import com.hazelcast.core.EntryEvent; import com.hazelcast.core.EntryListener; /** * CustomerEntryListener Class listens entry changes on named cache object. * * @author onlinetechvision.com * @since 27 Nov 2012 * @version 1.0.0 * */ @SuppressWarnings("rawtypes") public class CustomerEntryListener implements EntryListener { /** * Invoked when an entry is added. * * @param EntryEvent * */ public void entryAdded(EntryEvent ee) { System.out.println("EntryAdded... Member : " + ee.getMember() + ", Key : "+ee.getKey()+", OldValue : "+ee.getOldValue()+", NewValue : "+ee.getValue()); } /** * Invoked when an entry is removed. * * @param EntryEvent * */ public void entryRemoved(EntryEvent ee) { System.out.println("EntryRemoved... Member : " + ee.getMember() + ", Key : "+ee.getKey()+", OldValue : "+ee.getOldValue()+", NewValue : "+ee.getValue()); } /** * Invoked when an entry is evicted. * * @param EntryEvent * */ public void entryEvicted(EntryEvent ee) { } /** * Invoked when an entry is updated. * * @param EntryEvent * */ public void entryUpdated(EntryEvent ee) { } } STEP 11 : CREATE Starter CLASS Starter Class loads Customers to cache and executes distributed tasks. Starter Class of first member of the cluster : package com.onlinetechvision.exe; import com.onlinetechvision.cache.srv.ICacheService; import com.onlinetechvision.customer.Customer; /** * Starter Class loads Customers to cache and executes distributed tasks. * * @author onlinetechvision.com * @since 27 Nov 2012 * @version 1.0.0 * */ public class Starter { private ICacheService cacheService; /** * Loads cache and executes the tasks * */ public void start() { loadCacheForFirstMember(); } /** * Loads Customers to cache * */ public void loadCacheForFirstMember() { Customer firstCustomer = new Customer(); firstCustomer.setId("1"); firstCustomer.setName("Jodie"); firstCustomer.setSurname("Foster"); Customer secondCustomer = new Customer(); secondCustomer.setId("2"); secondCustomer.setName("Kate"); secondCustomer.setSurname("Winslet"); getCacheService().addToCache(firstCustomer.getId(), firstCustomer); getCacheService().addToCache(secondCustomer.getId(), secondCustomer); } public ICacheService getCacheService() { return cacheService; } public void setCacheService(ICacheService cacheService) { this.cacheService = cacheService; } } Starter Class of second member of the cluster : package com.onlinetechvision.exe; import java.util.Set; import java.util.concurrent.ExecutionException; import com.hazelcast.core.Hazelcast; import com.hazelcast.core.HazelcastInstance; import com.hazelcast.core.Member; import com.onlinetechvision.cache.srv.ICacheService; import com.onlinetechvision.customer.Customer; import com.onlinetechvision.exception.AnotherAvailableMemberNotFoundException; import com.onlinetechvision.executor.srv.IDistributedExecutorService; import com.onlinetechvision.task.TestCallable; /** * Starter Class loads Customers to cache and executes distributed tasks. * * @author onlinetechvision.com * @since 27 Nov 2012 * @version 1.0.0 * */ public class Starter { private String hazelcastInstanceName; private Hazelcast hazelcast; private IDistributedExecutorService distributedExecutorService; private ICacheService cacheService; /** * Loads cache and executes the tasks * */ public void start() { loadCache(); executeTasks(); } /** * Loads Customers to cache * */ public void loadCache() { Customer firstCustomer = new Customer(); firstCustomer.setId("3"); firstCustomer.setName("Bruce"); firstCustomer.setSurname("Willis"); Customer secondCustomer = new Customer(); secondCustomer.setId("4"); secondCustomer.setName("Colin"); secondCustomer.setSurname("Farrell"); getCacheService().addToCache(firstCustomer.getId(), firstCustomer); getCacheService().addToCache(secondCustomer.getId(), secondCustomer); } /** * Executes Tasks * */ public void executeTasks() { try { getDistributedExecutorService().executeOnStatedMember(new TestCallable(), getAnotherMember()); getDistributedExecutorService().executeOnTheMemberOwningTheKey(new TestCallable(), "3"); getDistributedExecutorService().executeOnAnyMember(new TestCallable()); getDistributedExecutorService().executeOnMembers(new TestCallable(), getAllMembers()); } catch (InterruptedException | ExecutionException | AnotherAvailableMemberNotFoundException e) { e.printStackTrace(); } } /** * Gets cluster members * * @return Set Set of Cluster Members * */ private Set getAllMembers() { Set members = getHazelcastLocalInstance().getCluster().getMembers(); return members; } /** * Gets an another member of cluster * * @return Member Another Member of Cluster * @throws AnotherAvailableMemberNotFoundException An Another Available Member can not found exception */ private Member getAnotherMember() throws AnotherAvailableMemberNotFoundException { Set members = getAllMembers(); for(Member member : members) { if(!member.localMember()) { return member; } } throw new AnotherAvailableMemberNotFoundException("No Other Available Member on the cluster. Please be aware that all members are active on the cluster"); } /** * Gets Hazelcast local instance * * @return HazelcastInstance Hazelcast local instance */ @SuppressWarnings("static-access") private HazelcastInstance getHazelcastLocalInstance() { HazelcastInstance instance = getHazelcast().getHazelcastInstanceByName(getHazelcastInstanceName()); return instance; } public String getHazelcastInstanceName() { return hazelcastInstanceName; } public void setHazelcastInstanceName(String hazelcastInstanceName) { this.hazelcastInstanceName = hazelcastInstanceName; } public Hazelcast getHazelcast() { return hazelcast; } public void setHazelcast(Hazelcast hazelcast) { this.hazelcast = hazelcast; } public IDistributedExecutorService getDistributedExecutorService() { return distributedExecutorService; } public void setDistributedExecutorService(IDistributedExecutorService distributedExecutorService) { this.distributedExecutorService = distributedExecutorService; } public ICacheService getCacheService() { return cacheService; } public void setCacheService(ICacheService cacheService) { this.cacheService = cacheService; } } STEP 12 : CREATE hazelcast-config.properties FILE hazelcast-config.properties file shows the properties of cluster members. First member properties : hz.instance.name = OTVInstance1 hz.group.name = dev hz.group.password = dev hz.management.center.enabled = true hz.management.center.url = http://localhost:8080/mancenter hz.network.port = 5701 hz.network.port.auto.increment = false hz.tcp.ip.enabled = true hz.members = 192.168.1.32 hz.executor.service.core.pool.size = 2 hz.executor.service.max.pool.size = 30 hz.executor.service.keep.alive.seconds = 30 hz.map.backup.count=2 hz.map.max.size=0 hz.map.eviction.percentage=30 hz.map.read.backup.data=true hz.map.cache.value=true hz.map.eviction.policy=NONE hz.map.merge.policy=hz.ADD_NEW_ENTRY Second member properties : hz.instance.name = OTVInstance2 hz.group.name = dev hz.group.password = dev hz.management.center.enabled = true hz.management.center.url = http://localhost:8080/mancenter hz.network.port = 5702 hz.network.port.auto.increment = false hz.tcp.ip.enabled = true hz.members = 192.168.1.32 hz.executor.service.core.pool.size = 2 hz.executor.service.max.pool.size = 30 hz.executor.service.keep.alive.seconds = 30 hz.map.backup.count=2 hz.map.max.size=0 hz.map.eviction.percentage=30 hz.map.read.backup.data=true hz.map.cache.value=true hz.map.eviction.policy=NONE hz.map.merge.policy=hz.ADD_NEW_ENTRY STEP 13 : CREATE applicationContext-hazelcast.xml Spring Hazelcast Configuration file, applicationContext-hazelcast.xml, is created and Hazelcast Distributed Executor Service and Hazelcast Instance are configured. ${hz.instance.name} ${hz.members} STEP 14 : CREATE applicationContext.xml Spring Configuration file, applicationContext.xml, is created. classpath:/hazelcast-config.properties STEP 15 : CREATE Application CLASS Application Class is created to run the application. ackage com.onlinetechvision.exe; import org.springframework.context.ApplicationContext; import org.springframework.context.support.ClassPathXmlApplicationContext; /** * Application class starts the application * * @author onlinetechvision.com * @since 27 Nov 2012 * @version 1.0.0 * */ public class Application { /** * Starts the application * * @param String[] args * */ public static void main(String[] args) { ApplicationContext context = new ClassPathXmlApplicationContext("applicationContext.xml"); Starter starter = (Starter) context.getBean("starter"); starter.start(); } } STEP 16 : BUILD PROJECT After OTV_Spring_Hazelcast_DistributedExecution Project is built, OTV_Spring_Hazelcast_DistributedExecution-0.0.1-SNAPSHOT.jar will be created. Important Note : The Members of the cluster have got different configuration for Coherence so the project should be built separately for each member. STEP 17 : INTEGRATION with HAZELCAST MANAGEMENT CENTER Hazelcast Management Center enables to monitor and manage nodes in the cluster. Entity and backup counts which are owned by customerMap, can be seen via Map Memory Data Table. We have distributed 4 entries via customerMap as shown below : Sample keys and values can be seen via Map Browser : Added First Entry : Added Third Entry : hazelcastDistributedExecutorService details can be seen via Executors tab. We have executed 3 task on first member and 2 tasks on second member as shown below : STEP 18 : RUN PROJECT BY STARTING THE CLUSTER’ s MEMBER After created OTV_Spring_Hazelcast_DistributedExecution-0.0.1-SNAPSHOT.jar file is run at the cluster’ s members, the following console output logs will be shown : First member console output : Kas 25, 2012 4:07:20 PM com.hazelcast.impl.AddressPicker INFO: Interfaces is disabled, trying to pick one address from TCP-IP config addresses: [x.y.z.t] Kas 25, 2012 4:07:20 PM com.hazelcast.impl.AddressPicker INFO: Prefer IPv4 stack is true. Kas 25, 2012 4:07:20 PM com.hazelcast.impl.AddressPicker INFO: Picked Address[x.y.z.t]:5701, using socket ServerSocket[addr=/0:0:0:0:0:0:0:0,localport=5701], bind any local is true Kas 25, 2012 4:07:21 PM com.hazelcast.system INFO: [x.y.z.t]:5701 [dev] Hazelcast Community Edition 2.4 (20121017) starting at Address[x.y.z.t]:5701 Kas 25, 2012 4:07:21 PM com.hazelcast.system INFO: [x.y.z.t]:5701 [dev] Copyright (C) 2008-2012 Hazelcast.com Kas 25, 2012 4:07:21 PM com.hazelcast.impl.LifecycleServiceImpl INFO: [x.y.z.t]:5701 [dev] Address[x.y.z.t]:5701 is STARTING Kas 25, 2012 4:07:24 PM com.hazelcast.impl.TcpIpJoiner INFO: [x.y.z.t]:5701 [dev] --A new cluster is created and First Member joins the cluster. Members [1] { Member [x.y.z.t]:5701 this } Kas 25, 2012 4:07:24 PM com.hazelcast.impl.MulticastJoiner INFO: [x.y.z.t]:5701 [dev] Members [1] { Member [x.y.z.t]:5701 this } ... -- First member adds two new entries to the cache... EntryAdded... Member : Member [x.y.z.t]:5701 this, Key : 1, OldValue : null, NewValue : Customer [id=1, name=Jodie, surname=Foster] EntryAdded... Member : Member [x.y.z.t]:5701 this, Key : 2, OldValue : null, NewValue : Customer [id=2, name=Kate, surname=Winslet] ... --Second Member joins the cluster. Members [2] { Member [x.y.z.t]:5701 this Member [x.y.z.t]:5702 } ... -- Second member adds two new entries to the cache... EntryAdded... Member : Member [x.y.z.t]:5702, Key : 4, OldValue : null, NewValue : Customer [id=4, name=Colin, surname=Farrell] EntryAdded... Member : Member [x.y.z.t]:5702, Key : 3, OldValue : null, NewValue : Customer [id=3, name=Bruce, surname=Willis] Second member console output : Kas 25, 2012 4:07:48 PM com.hazelcast.impl.AddressPicker INFO: Interfaces is disabled, trying to pick one address from TCP-IP config addresses: [x.y.z.t] Kas 25, 2012 4:07:48 PM com.hazelcast.impl.AddressPicker INFO: Prefer IPv4 stack is true. Kas 25, 2012 4:07:48 PM com.hazelcast.impl.AddressPicker INFO: Picked Address[x.y.z.t]:5702, using socket ServerSocket[addr=/0:0:0:0:0:0:0:0,localport=5702], bind any local is true Kas 25, 2012 4:07:49 PM com.hazelcast.system INFO: [x.y.z.t]:5702 [dev] Hazelcast Community Edition 2.4 (20121017) starting at Address[x.y.z.t]:5702 Kas 25, 2012 4:07:49 PM com.hazelcast.system INFO: [x.y.z.t]:5702 [dev] Copyright (C) 2008-2012 Hazelcast.com Kas 25, 2012 4:07:49 PM com.hazelcast.impl.LifecycleServiceImpl INFO: [x.y.z.t]:5702 [dev] Address[x.y.z.t]:5702 is STARTING Kas 25, 2012 4:07:49 PM com.hazelcast.impl.Node INFO: [x.y.z.t]:5702 [dev] ** setting master address to Address[x.y.z.t]:5701 Kas 25, 2012 4:07:49 PM com.hazelcast.impl.MulticastJoiner INFO: [x.y.z.t]:5702 [dev] Connecting to master node: Address[x.y.z.t]:5701 Kas 25, 2012 4:07:49 PM com.hazelcast.nio.ConnectionManager INFO: [x.y.z.t]:5702 [dev] 55715 accepted socket connection from /x.y.z.t:5701 Kas 25, 2012 4:07:55 PM com.hazelcast.cluster.ClusterManager INFO: [x.y.z.t]:5702 [dev] --Second Member joins the cluster. Members [2] { Member [x.y.z.t]:5701 Member [x.y.z.t]:5702 this } Kas 25, 2012 4:07:56 PM com.hazelcast.impl.LifecycleServiceImpl INFO: [x.y.z.t]:5702 [dev] Address[x.y.z.t]:5702 is STARTED -- Second member adds two new entries to the cache... EntryAdded... Member : Member [x.y.z.t]:5702 this, Key : 3, OldValue : null, NewValue : Customer [id=3, name=Bruce, surname=Willis] EntryAdded... Member : Member [x.y.z.t]:5702 this, Key : 4, OldValue : null, NewValue : Customer [id=4, name=Colin, surname=Farrell] 25.11.2012 16:07:56 DEBUG (DistributedExecutorService.java:42) - Method executeOnStatedMember is called... 25.11.2012 16:07:56 DEBUG (DistributedExecutorService.java:46) - Result of method executeOnStatedMember is : First Member' s TestCallable Task is called... 25.11.2012 16:07:56 DEBUG (DistributedExecutorService.java:61) - Method executeOnTheMemberOwningTheKey is called... 25.11.2012 16:07:56 DEBUG (DistributedExecutorService.java:65) - Result of method executeOnTheMemberOwningTheKey is : First Member' s TestCallable Task is called... 25.11.2012 16:07:56 DEBUG (DistributedExecutorService.java:78) - Method executeOnAnyMember is called... 25.11.2012 16:07:57 DEBUG (DistributedExecutorService.java:82) - Result of method executeOnAnyMember is : Second Member' s TestCallable Task is called... 25.11.2012 16:07:57 DEBUG (DistributedExecutorService.java:96) - Method executeOnMembers is called... 25.11.2012 16:07:57 DEBUG (DistributedExecutorService.java:101) - Result of method executeOnMembers is : [First Member' s TestCallable Task is called..., Second Member' s TestCallable Task is called...] STEP 19 : DOWNLOAD https://github.com/erenavsarogullari/OTV_Spring_Hazelcast_DistributedExecution REFERENCES : Java ExecutorService Interface Hazelcast Distributed Executor Service
December 11, 2012
by Eren Avsarogullari
· 30,135 Views · 1 Like
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Enterprise-ready Tool Support for Apache Camel
apache camel is my favorite integration framework on the java platform due to great dsls, a huge community, and so many different components. camel is used by many developers from different companies all over the world. however, most guys are not aware that some really cool and – more important – enterprise-ready tooling is available for camel, too. many people ask me about camel tooling when i do talks at conferences. this is the reason for this short blog post about camel tooling. [fyi: i work for talend (one of the vendors).] ide support camel consists of a set of normal java libraries and is therefore usable with any java ide (such as eclipse, netbeans or intellij idea) or even a classic text editor. programming dsls are available for java, groovy, and scala. even a kotlin dsl is in the works, thanks to camel’s founder james strachan. all familiar ide features such as code completion or javadoc view are available for these dsls. in the spring xml dsl, the eclipse-based springsource tool suite (sts) should be emphasized, which provides the best support for the spring framework and xml configurations. camel-specific tooling besides classical ide support, further products are available to provide additional functionality. integration problems can be modeled with the help of enterprise integration patterns (eip, http://www.eaipatterns.com/). eips are implemented by camel. visual designers are available to help modeling integration problems with these eips. these tools even generate the corresponding source code automatically. ideally, developers do not have to write any source code by hand. camel tooling is offered by talend with talend esb (http://de.talend.com/products/esb) and jboss, formerly fusesource, with fuse ide (http://fusesource.com/products/fuse-ide). both companies also provide full-time committers for the apache camel project. let’s take a short look at these two products in the following. open studio for talend esb talend esb is an eclipse-based integration platform within the talend unified platform. the familiar “look and feel” and the intuitive use of eclipse remain. the esb is open source and freely available. the paid enterprise version offers additional features and support. the esb can be used independently or in combination with other parts of the talend unified platform, such as BPM, big data, or master data management. the great benefit is that everything can be done within one suite using the same gui and concepts, based on eclipse. the entire talend unified platform is based on the “zero-coding” approach. this way, a very efficient implementation of integration problems is possible using the eips and components. routes are modeled and configured with intuitive tool support, all source code is generated. of course, custom integration logic can still be written and included, for example, pojos, spring beans, scripts in different languages, or own camel components. plenty of other components besides camel’s ones are available for talend esb – for example connectors to alfresco, jasper, sap, salesforce, or host systems. figure 1: visual designer of talend’s esb fuse ide the fuse ide is an eclipse plugin, which is installed from the eclipse update site. the visual designer (see figure 2) generates camel routes as xml code using the spring xml dsl. the generated code is editable vice-versa, i.e. the developer can change the source code. the graphical model applies changes automatically. fuse ide is intuitive to use for creating camel routes. fusesource offers some other products, which can be used in combination with fuse ide – such as management console or fuse mq for messaging. under fusesource, fuse ide was a proprietary product. however, fusesource was recently taken over by redhat (http://www.redhat.com/about/news/press-archive/2012/6/red-hat-to-acquire-fusesource) and now belongs to the jboss division. in the new roadmap, the fuse ide is still included. it will probably be integrated into the jboss enterprise soa platform and become “open sourced”. the integration of fusesource will take at least a few more months time to complete (http://www.redhat.com/promo/jboss_integration_week/). jboss now “owns” three esb products (jboss esb, switchyard and fuse esb). probably, these will be merged into one product in the end (switchyard is also based on camel). nevertheless, the fusesource products will also be supported for some time – primarily in order to satisfy existing customers (my guess). figure 2: visual designer of fuse ide (jboss, former fusesource) enterprise-ready tooling is already available for apache camel! the bottom line is that enterprise-ready tooling is already available for apache camel. it is great to see different companies working on tooling for apache camel. the winner definitely is apache camel… and there is no loser! talend esb and fuse ide are two different approaches for different kinds of projects. if you like the „zero-coding“ approach, then take a closer look at talend’s esb. it is really easy and efficient to realize integration projects without writing source code – nevertheless, there is enough flexibility for customization and adding own source code. the combination with bpm, mdm or big data (based on hadoop) is also supported within the unified platform using the same open source and „zero-coding“ concepts. if you „insist“ on writing and refactoring all source code by yourself within the text editor of an ide, then take a look at fuse ide. your best would be to try out both and see which one fits best into your next enterprise integration project. if you know any other cool camel tooling (no matter if it is enterprise-ready or not), or if you have any other feedback, please write a comment. thank you. best regards, kai wähner (twitter: @kaiwaehner) content from my blog: http://www.kai-waehner.de/blog/2012/11/23/enterprise-ready-tool-support-for-apache-camel/
November 26, 2012
by Kai Wähner DZone Core CORE
· 15,724 Views
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A Node.js speed dilemma: AJAX or Socket.IO?
Originally posted by Daniel Chirca One the first things I stumbled upon when I started my first Node.js project was how to handle the communication between the browser (the client) and my middleware (the middleware being a Node.js application using the CUBRID Node.js driver (node-cubrid) to exchange information with a CUBRID 8.4.1 database). I am already familiar with AJAX (btw, thanks God for jQuery!! ) but, while studying Node.js, I found out about the Socket.IO module and even found some pretty nice code examples on the internet... Examples which were very-very easy to (re)use... So this quickly become a dilemma: what to choose, AJAX or sockets.io? Obviously, as my experience was quite limited, I needed first more information from out there... In other words, it was time to do some quality Google search :) There’s a lot of information available and, obviously, one would need to filter out all the “noise” and keep what is really useful. Let me share with you some of the goods links I found on the topic: http://stackoverflow.com/questions/7193033/nodejs-ajax-vs-socket-io-pros-and-cons http://podefr.tumblr.com/post/22553968711/an-innovative-way-to-replace-ajax-and-jsonp-using http://stackoverflow.com/questions/4848642/what-is-the-disadvantage-of-using-websocket-socket-io-where-ajax-will-do?rq=1 http://howtonode.org/websockets-socketio To summarize, here’s what I quickly found: Socket.IO (usually) uses persistent connection between the client and the server (the middleware), so you can reach a maximum limit of concurrent connections depending on the resources you have on server side (while more AJAX async requests can be served with the same resources). With AJAX you can do RESTful requests. This means that you can take advantage of existing HTTP-infrastructure like e.g. proxies to cache requests and use conditional get requests. There is more (communication) data overhead in AJAX when compared to Socket.IO (HTTP headers, cookies etc.) AJAX is usually faster than Socket.IO to “code”... When using Socket.IO, it is possible to have a two-way communication where each side – client or server - can initiate a request. In AJAX, it is only the client who can initiate a request! Socket.IO has more transport options, including Adobe Flash. Now, for my own application, what I was most interested in was the speed of making requests and getting data from the (Node.js) server! Regarding the middleware data communication with the CUBRID database, as ~90% of my data access was read-only, a good data caching mechanism is obviously a great way to go! But about this, I’ll talk next time. So I decided to put up their (AJAX and socket.io) speed to test, to see which one is faster (at least on my hardware & software environment)....! My middleware was setup to run on an i5 processor, 8GB of RAM and an Intel X25 SSD drive. But seriously, every speed test and, generally speaking, any performance test depends so much(!) on your hardware and software configuration, that it is always a great idea to try the things on your own environment, rely less on various information you find on internet and more on your own findings! The tests I decided to do have to meet the following requirements: Test: AJAX Socket.IO persistent connection Socket.IO non-persistent connections Test 10, 100, 250 and 500 data exchanges between the client and the server Each data exchange between the middleware SERVER (a Node.js web server) and the client (a browser) is a 4KBytes random data string Run the server in release (not debug) mode Use Firefox as the client Minimize the console messages output, for both server and client Do each test after a client full page reload Repeat each test at least 3 times, to make sure the results are consistent Testing Socket.IO, using a persistent connection I've created a small Node.js server, which was handling the client requests: io.sockets.on('connection', function (client) { client.on('send_me_data', function (idx) { client.emit('you_have_data', idx, random_string(4096)); }); }); And this is the JS client script I used for test: var socket = io.connect(document.location.href); socket.on('you_have_data', function (idx, data) { var end_time = new Date(); total_time += end_time - start_time; logMsg(total_time + '(ms.) [' + idx + '] - Received ' + data.length + ' bytes.'); if (idx++ < countMax) { setTimeout(function () { start_time = new Date(); socket.emit('send_me_data', idx); }, 500); } }); Testing Socket.IO, using NON-persistent connection This time, for each data exchange, I opened a new socket-io connection. The Node.js server code was similar with the previous one, but I decided to send back the client data immediately after connect, as a new connection was initiated every time, for each data exchange: io.sockets.on('connection', function (client) { client.emit('you_have_data', random_string(4096)); }); The client test code was: function exchange(idx) { var start_time = new Date(); var socket = io.connect(document.location.href, {'force new connection' : true}); socket.on('you_have_data', function (data) { var end_time = new Date(); total_time += end_time - start_time; socket.removeAllListeners(); socket.disconnect(); logMsg(total_time + '(ms.) [' + idx + '] - Received ' + data.length + ' bytes.'); if (idx++ < countMax) { setTimeout(function () { exchange(idx); }, 500); } }); } Testing AJAX Finally, I put AJAX to test... The Node.js server code was, again, not that different from the previous ones: res.writeHead(200, {'Content-Type' : 'text/plain'}); res.end('_testcb(\'{"message": "' + random_string(4096) + '"}\')'); As for the client code, this is what I used to test: function exchange(idx) { var start_time = new Date(); $.ajax({ url : 'http://localhost:8080/', dataType : "jsonp", jsonpCallback : "_testcb", timeout : 300, success : function (data) { var end_time = new Date(); total_time += end_time - start_time; logMsg(total_time + '(ms.) [' + idx + '] - Received ' + data.length + ' bytes.'); if (idx++ < countMax) { setTimeout(function () { exchange(idx); }, 500); } }, error : function (jqXHR, textStatus, errorThrown) { alert('Error: ' + textStatus + " " + errorThrown); } }); } Remember, when coding together AJAX and Node.js, you need to take into account the you might be doing cross-domain requests and violating same origin policy, therefore you should use the JSONP based format! Btw, as you can see, I quoted only the most significant parts of the test code, to save space. If anyone needs the full code, server and client, please let me know – I’ll be happy to share them. OK – it’s time now to see what we got after all this work! I have run each test for 10, 100, 250 and 500 data exchanges and this is what I got in the end: Data exchanges Socket.IO NON-persistent (ms.) AJAX (ms.) Socket.IO persistent (ms.) 10 90 40 32 100 900 320 340 250 2,400 800 830 500 4,900 1,500 1,600 Looking into the results, we can notice a few things right away: For each type of test, the results behave quite linear; this is good – it shows that the results are consistent. The results clearly show that when using Socket.IO non-persistent connections, the performance numbers are significantly worse than others. It doesn’t seem to be a big difference between AJAX and the Socket.IO persistent connections – we are talking only about some milliseconds differences. This means that if you can live with less than 10,000 data exchanges per day, for example, there are high chances that the user won’t notice a speed difference... The graph below illustrates the numbers I obtained in test: ...So what’s next...? ...Well, I have to figure out what kind of traffic I need to support and then I will re-run the tests for those numbers, but this time excluding Socket.IO non-persistent connections. That’s because it is obvious that I need to choose between AJAX and persistent Socket.IO connections. And I also learned that, most probably, the difference in speed would not be as much as one would expect... at least not for a “small-traffic” web site, so I need to start looking into other advantages and disadvantages for each approach/technology when choosing my solution! That’s pretty much for this post - see you next time with a post about Node.js and caching! P.S. Here are a few more nice resources to find interesting stuff about Node.js, Socket.IO and AJAX: http://socket.io/#how-to-use http://www.hacksparrow.com/jquery-with-node-js.html http://www.slideshare.net/toddeichel/nodejs-talk-at-jquery-pittsburgh http://tech.burningbird.net/article/node-references-and-resources http://davidwalsh.name/websocket
November 22, 2012
by Esen Sagynov
· 17,633 Views
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Spring JMS, Message Automatic Conversion, JMS Template
In one of my projects I was supposed to create a message router that like all routers was supposed to take the JMS messages from one topic and put it into another one. The message itself was a JMS text message that in fact contained an XML message. What is more after having received it I was supposed to enrich the message with some additional data. We were not allowed to use neither Spring nor JAXB nor any other useful library so I decided to check how easy it would be to do it using them. Initially I wanted to use only Spring and JAXB but in the next post I will try to repeat the same scenario by using Apache Camel (that's why you will find the word "camel" in the package name). The JMS communication was present thanks to the ActiveMQ messaging server. Anyway coming back to the code. I used maven to resolve dependencies and these are the dependencies that were mandatory i n terms of JMS and JAXB and message conversion: pom.xml org.springframework spring-jms 3.1.1.RELEASE com.sun.xml.bind jaxb-impl 2.2.6 org.springframework spring-oxm 3.1.1.RELEASE This is how I divided the project (the camel part of the package will make more sense in the next article). In order to have my message converted to objects via JAXB I needed a schema: Player.xsd I had to download JAXB binaries and executed the following command to have my objects created: ./xjc.sh -p pl.grzejszczak.marcin.camel.jaxb.generated ~/PATH/TO/THE/SCHEMA/FILE/Player.xsd An example of the outcome of this command is the: PlayerDetails.java // // This file was generated by the JavaTM Architecture for XML Binding(JAXB) Reference Implementation, v2.2.6 // See http://java.sun.com/xml/jaxb // Any modifications to this file will be lost upon recompilation of the source schema. // Generated on: 2012.11.05 at 09:23:22 PM CET // package pl.grzejszczak.marcin.camel.jaxb.generated; import javax.xml.bind.annotation.XmlAccessType; import javax.xml.bind.annotation.XmlAccessorType; import javax.xml.bind.annotation.XmlElement; import javax.xml.bind.annotation.XmlRootElement; import javax.xml.bind.annotation.XmlType; /** * Java class for anonymous complex type. * * The following schema fragment specifies the expected content contained within this class. * * * * * * * * * * * * * * * * * * */ @XmlAccessorType(XmlAccessType.FIELD) @XmlType(name = "", propOrder = { "name", "surname", "position", "age", "teamName" }) @XmlRootElement(name = "PlayerDetails") public class PlayerDetails { @XmlElement(name = "Name", required = true) protected String name; @XmlElement(name = "Surname", required = true) protected String surname; @XmlElement(name = "Position", required = true) protected PositionType position; @XmlElement(name = "Age") protected int age; @XmlElement(name = "TeamName", required = true) protected String teamName; /** * Gets the value of the name property. * * @return * possible object is * {@link String } * */ public String getName() { return name; } /** * Sets the value of the name property. * * @param value * allowed object is * {@link String } * */ public void setName(String value) { this.name = value; } /** * Gets the value of the surname property. * * @return * possible object is * {@link String } * */ public String getSurname() { return surname; } /** * Sets the value of the surname property. * * @param value * allowed object is * {@link String } * */ public void setSurname(String value) { this.surname = value; } /** * Gets the value of the position property. * * @return * possible object is * {@link PositionType } * */ public PositionType getPosition() { return position; } /** * Sets the value of the position property. * * @param value * allowed object is * {@link PositionType } * */ public void setPosition(PositionType value) { this.position = value; } /** * Gets the value of the age property. * */ public int getAge() { return age; } /** * Sets the value of the age property. * */ public void setAge(int value) { this.age = value; } /** * Gets the value of the teamName property. * * @return * possible object is * {@link String } * */ public String getTeamName() { return teamName; } /** * Sets the value of the teamName property. * * @param value * allowed object is * {@link String } * */ public void setTeamName(String value) { this.teamName = value; } } The @XmlRootElement(name = "PlayerDetails") means that this class will output a Root node in the XML file. The @XmlAccessorType(XmlAccessType.FIELD) as the JavaDoc says means that "Every non static, non transient field in a JAXB-bound class will be automatically bound to XML, unless annotated by XmlTransient." In other words, if you have a field annotated by the XmlTransient annotation it won't get serialized. Then we have the @XmlType(name = "", propOrder = { "name", "surname", "position", "age", "teamName" })which as JavaDoc sates "Maps a class or an enum type to a XML Schema type" . In other words our class is mapped to the PlayerDetails element in the schema. Finally we have the @XmlElement(name = "Name", required = true) annotation which is a mapping of the XML node (element) to a field in the class. This is my message to be sent, received, enriched and routed: RobertLewandowski.xml Robert Lewandowski ATT Now off to my JMS configuration - I have configured the Queues of origin and destination jms.properties jms.origin=Initial.Queue jms.destination=Routed.Queue This is my Spring configuration (I added comments inside the config that explain the origin of those components): jmsApplicationContext.xml Now let's take a look at the Java code - let's start with the class that has the main function ActiveMQRouter.java package pl.grzejszczak.marcin.camel.manual; import java.io.File; import java.util.Scanner; import javax.jms.JMSException; import org.springframework.context.ApplicationContext; import org.springframework.context.support.ClassPathXmlApplicationContext; import org.springframework.core.io.ClassPathResource; import org.springframework.core.io.Resource; import pl.grzejszczak.marcin.camel.jaxb.PlayerDetailsConverter; import pl.grzejszczak.marcin.camel.jaxb.generated.PlayerDetails; import pl.grzejszczak.marcin.camel.manual.jms.Sender; public class ActiveMQRouter { /** * @param args * @throws JMSException */ public static void main(String[] args) throws Exception { ApplicationContext context = new ClassPathXmlApplicationContext("/camel/jmsApplicationContext.xml"); @SuppressWarnings("unchecked") Sender sender = (Sender) context.getBean("originPlayerSender"); Resource resource = new ClassPathResource("/camel/RobertLewandowski.xml"); Scanner scanner = new Scanner(new File(resource.getURI())).useDelimiter("\\Z"); String contents = scanner.next(); PlayerDetailsConverter converter = context.getBean(PlayerDetailsConverter.class); sender.sendMessage(converter.unmarshal(contents)); } } What we can see here is that we initialize the Spring context from the classpath and retrieve the bean named originPlayerSender. This component is used for sending a message to the initial queue. In order to have a message to send we are retrieving a file RobertLewandowski.xml from the classpath and read it to a String variable through the Scanner class. Next we use our custom PlayerDetailsConverter class to unmarshall the String contents into a PlayerDetails object, which in effect is sent by the originPlayerSender to the origin queue. Now let's take a look at the sender logic: PlayerDetailsSenderImpl.java package pl.grzejszczak.marcin.camel.manual.jms; import javax.jms.Destination; import javax.jms.JMSException; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.jms.core.JmsTemplate; import org.springframework.stereotype.Component; import pl.grzejszczak.marcin.camel.jaxb.generated.PlayerDetails; @Component public class PlayerDetailsSenderImpl implements Sender { private static final Logger LOGGER = LoggerFactory.getLogger(PlayerDetailsSenderImpl.class); private Destination destination; @Autowired private JmsTemplate jmsTemplate; @Override public void sendMessage(final PlayerDetails object) throws JMSException { LOGGER.debug("Sending [{}] to topic [{}]", new Object[] { object, destination }); jmsTemplate.convertAndSend(destination, object); } public Destination getDestination() { return destination; } public void setDestination(Destination destination) { this.destination = destination; } } This class is implementing my Sender interface that provides the sendMessage function. We are using the JmsTemplate object to convert and send the message to the given destination that is injected via Spring. Ok, now that we've sent the message someone has to retrieve it: ListenerImpl.java package pl.grzejszczak.marcin.camel.manual.jms; import java.util.List; import javax.jms.BytesMessage; import javax.jms.Message; import javax.jms.MessageListener; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.beans.factory.annotation.Qualifier; import org.springframework.jms.support.converter.MessageConverter; import org.springframework.stereotype.Component; import pl.grzejszczak.marcin.camel.enricher.Enrichable; import pl.grzejszczak.marcin.camel.jaxb.Convertable; import pl.grzejszczak.marcin.camel.jaxb.generated.PlayerDetails; @Component public class ListenerImpl implements MessageListener { private static final Logger LOG = LoggerFactory.getLogger(ListenerImpl.class); @Autowired private Convertable playerDetailsConverter; @Autowired private List> listOfEnrichers; @Autowired private MessageConverter messageConverter; @Autowired @Qualifier("destinationPlayerSender") private Sender sender; @Override public void onMessage(Message message) { if (!(message instanceof BytesMessage)) { LOG.error("Wrong msg!"); return; } PlayerDetails playerDetails = null; try { playerDetails = (PlayerDetails) messageConverter.fromMessage(message); LOG.debug("Enriching the input message"); for (Enrichable enrichable : listOfEnrichers) { enrichable.enrich(playerDetails); } LOG.debug("Enriched text message: [{}]", new Object[] { playerDetailsConverter.marshal(playerDetails) }); sender.sendMessage(playerDetails); } catch (Exception e) { LOG.error("Exception occured", e); } } } This class has the list of all the classes implementing the Enrichable interface thanks to which it will provide the enrichment of the message without the necessity of knowing the amount of enrichers in the system. There is also the PlayerDetailsConverter class that helps with marshalling and unmarshalling PlayerDetails. Once the message is enriched it is sent to the destination queue through the bean that implements the Sender interface and has the id of destinationPlayerSender. It is important to remember that what we receive from the queue is a BytesMessage thus that's why we are doing the initial check. Let's take a look at one of the enrichers (the other one is a setting another field in the PlayerDetails object) ClubEnricher.java package pl.grzejszczak.marcin.camel.enricher; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import org.springframework.stereotype.Component; import pl.grzejszczak.marcin.camel.jaxb.generated.PlayerDetails; @Component("ClubEnricher") public class ClubEnricher implements Enrichable { private static final Logger LOGGER = LoggerFactory.getLogger(ClubEnricher.class); @Override public void enrich(PlayerDetails inputObject) { LOGGER.debug("Enriching player [{}] with club data", new Object[] { inputObject.getSurname() }); // Simulating accessing DB or some other service try { Thread.sleep(2000); } catch (InterruptedException e) { LOGGER.error("Exception while sleeping occured", e); } inputObject.setTeamName("Borussia Dortmund"); } } As you can see the class is just simulating some access to the DB or any other service and afterwards is setting the team name in the input PlayerDetails object. Let's now take a look a the conversion mechanism: PlayerDetailsConverter.java package pl.grzejszczak.marcin.camel.jaxb; import java.io.ByteArrayOutputStream; import java.io.OutputStream; import javax.xml.bind.JAXBContext; import javax.xml.bind.JAXBException; import javax.xml.bind.Marshaller; import javax.xml.bind.Unmarshaller; import org.apache.activemq.util.ByteArrayInputStream; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import org.springframework.stereotype.Component; import pl.grzejszczak.marcin.camel.jaxb.generated.PlayerDetails; @Component("PlayerDetailsConverter") public class PlayerDetailsConverter implements Convertable { private static final Logger LOGGER = LoggerFactory.getLogger(PlayerDetailsConverter.class); private final JAXBContext jaxbContext; private final Marshaller jaxbMarshaller; private final Unmarshaller jaxbUnmarshaller; public PlayerDetailsConverter() throws JAXBException { jaxbContext = JAXBContext.newInstance(PlayerDetails.class); jaxbMarshaller = jaxbContext.createMarshaller(); jaxbMarshaller.setProperty(Marshaller.JAXB_FORMATTED_OUTPUT, true); jaxbUnmarshaller = jaxbContext.createUnmarshaller(); } @Override public String marshal(PlayerDetails object) { OutputStream stream = new ByteArrayOutputStream(); try { jaxbMarshaller.marshal(object, stream); } catch (JAXBException e) { LOGGER.error("Exception occured while marshalling", e); } return stream.toString(); } @Override public PlayerDetails unmarshal(String objectAsString) { try { return (PlayerDetails) jaxbUnmarshaller.unmarshal(new ByteArrayInputStream(objectAsString.getBytes())); } catch (JAXBException e) { LOGGER.error("Exception occured while marshalling", e); } return null; } } In the constructor we are setting some JAXB components - the JAXBContext, JAXB Marshaller and JAXB Unmarshaller that have the necessary marshal and unmarshal methods. Last but not least is the FinalListenerImpl that is listening to the inbound message from the destination queue and shuts the application. FinalListenerImpl.java package pl.grzejszczak.marcin.camel.manual.jms; import javax.jms.BytesMessage; import javax.jms.Message; import javax.jms.MessageListener; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.jms.support.converter.MessageConverter; import org.springframework.stereotype.Component; import pl.grzejszczak.marcin.camel.jaxb.generated.PlayerDetails; @Component public class FinalListenerImpl implements MessageListener { private static final Logger LOG = LoggerFactory.getLogger(FinalListenerImpl.class); @Autowired private MessageConverter messageConverter; @Override public void onMessage(Message message) { if (!(message instanceof BytesMessage)) { LOG.error("Wrong msg!"); return; } PlayerDetails playerDetails = null; try { playerDetails = (PlayerDetails) messageConverter.fromMessage(message); if (playerDetails.getTeamName() != null) { LOG.debug("Message already enriched! Shutting down the system"); } else { LOG.debug("The message should have been enriched but wasn't"); } } catch (Exception e) { LOG.error("Exception occured", e); } finally { System.exit(0); } } } By using the MessageConverter, after having verified if the message is of proper type, we check if the team name has already been filled in - if that is the case we are terminating the application. And the logs are as follows: 2012-11-05 [main] org.springframework.context.support.ClassPathXmlApplicationContext:495 Refreshing org.springframework.context.support.ClassPathXmlApplicationContext@34fbb7cb: startup date [Mon Nov 05 21:47:00 CET 2012]; root of context hierarchy 2012-11-05 [main] org.springframework.beans.factory.xml.XmlBeanDefinitionReader:315 Loading XML bean definitions from class path resource [camel/jmsApplicationContext.xml] 2012-11-05 [main] org.springframework.beans.factory.config.PropertyPlaceholderConfigurer:177 Loading properties file from class path resource [camel/jms.properties] 2012-11-05 [main] org.springframework.beans.factory.support.DefaultListableBeanFactory:557 Pre-instantiating singletons in org.springframework.beans.factory.support.DefaultListableBeanFactory@3313beb5: defining beans [org.springframework.context.annotation.internalConfigurationAnnotationProcessor,org.springframework.context.annotation.internalAutowiredAnnotationProcessor,org.springframework.context.annotation.internalRequiredAnnotationProcessor,org.springframework.context.annotation.internalCommonAnnotationProcessor,org.springframework.context.annotation.internalPersistenceAnnotationProcessor,myRoute,AgeEnricher,ClubEnricher,PlayerDetailsConverter,finalListenerImpl,listenerImpl,playerDetailsSenderImpl,org.springframework.beans.factory.config.PropertyPlaceholderConfigurer#0,activeMQConnectionFactory,cachingConnectionFactory,origin,destination,producerTemplate,originPlayerSender,destinationPlayerSender,originListenerImpl,destinationListenerImpl,jmsOriginContainer,jmsDestinationContainer,oxmMessageConverter,marshaller,org.springframework.context.annotation.ConfigurationClassPostProcessor$ImportAwareBeanPostProcessor#0]; root of factory hierarchy 2012-11-05 [main] org.springframework.oxm.jaxb.Jaxb2Marshaller:436 Creating JAXBContext with classes to be bound [class pl.grzejszczak.marcin.camel.jaxb.generated.PlayerDetails] 2012-11-05 [main] org.springframework.context.support.DefaultLifecycleProcessor:334 Starting beans in phase 2147483647 2012-11-05 [main] org.springframework.jms.connection.CachingConnectionFactory:291 Established shared JMS Connection: ActiveMQConnection {id=ID:marcin-SR700-38535-1352148424687-1:1,clientId=null,started=false} 2012-11-05 [main] pl.grzejszczak.marcin.camel.manual.jms.PlayerDetailsSenderImpl:26 Sending [pl.grzejszczak.marcin.camel.jaxb.generated.PlayerDetails@6ae2d0b2] to topic [queue://Initial.Queue] 2012-11-05 [jmsOriginContainer-1] pl.grzejszczak.marcin.camel.manual.jms.ListenerImpl:49 Enriching the input message 2012-11-05 [jmsOriginContainer-1] pl.grzejszczak.marcin.camel.enricher.AgeEnricher:17 Enriching player [Lewandowski] with age data 2012-11-05 [jmsOriginContainer-1] pl.grzejszczak.marcin.camel.enricher.ClubEnricher:16 Enriching player [Lewandowski] with club data 2012-11-05 [jmsOriginContainer-1] pl.grzejszczak.marcin.camel.manual.jms.ListenerImpl:53 Enriched text message: [ Robert Lewandowski ATT 19 Borussia Dortmund ] 2012-11-05 [jmsOriginContainer-1] pl.grzejszczak.marcin.camel.manual.jms.PlayerDetailsSenderImpl:26 Sending [pl.grzejszczak.marcin.camel.jaxb.generated.PlayerDetails@3dca1588] to topic [queue://Routed.Queue] 2012-11-05 [jmsDestinationContainer-1] pl.grzejszczak.marcin.camel.manual.jms.FinalListenerImpl:35 Message already enriched! Shutting down the system This is how thanks to the Spring JMS module and the JAXB library you can easilly create JMS listeners, senders and message convertors for the XML messages.
November 13, 2012
by Marcin Grzejszczak
· 75,916 Views · 2 Likes
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Integration Testing with MongoDB & Spring Data
Integration Testing is an often overlooked area in enterprise development. This is primarily due to the associated complexities in setting up the necessary infrastructure for an integration test. For applications backed by databases, it’s fairly complicated and time-consuming to setup databases for integration tests, and also to clean those up once test is complete (ex. data files, schemas etc.), to ensure repeatability of tests. While there have been many tools (ex. DBUnit) and mechanisms (ex. rollback after test) to assist in this, the inherent complexity and issues have been there always. But if you are working with MongoDB, there’s a cool and easy way to do your unit tests, with almost the simplicity of writing a unit test with mocks. With ‘EmbedMongo’, we can easily setup an embedded MongoDB instance for testing, with in-built clean up support once tests are complete. In this article, we will walkthrough an example where EmbedMongo is used with JUnit for integration testing a Repository Implementation. Here’s the technology stack that we will be using. MongoDB 2.2.0 EmbedMongo 1.26 Spring Data – Mongo 1.0.3 Spring Framework 3.1 The Maven POM for the above setup looks like this. 4.0.0 com.yohanliyanage.blog.mongoit mongo-it 1.0 org.springframework.data spring-data-mongodb 1.0.3.RELEASE compile junit junit 4.10 test org.springframework spring-context 3.1.3.RELEASE compile de.flapdoodle.embed de.flapdoodle.embed.mongo 1.26 test Or if you prefer Gradle (by the way, Gradle is an awesome build tool which you should check out if you haven’t done so already). apply plugin: 'java' apply plugin: 'eclipse' sourceCompatibility = 1.6 group = "com.yohanliyanage.blog.mongoit" version = '1.0' ext.springVersion = '3.1.3.RELEASE' ext.junitVersion = '4.10' ext.springMongoVersion = '1.0.3.RELEASE' ext.embedMongoVersion = '1.26' repositories { mavenCentral() maven { url 'http://repo.springsource.org/release' } } dependencies { compile "org.springframework:spring-context:${springVersion}" compile "org.springframework.data:spring-data-mongodb:${springMongoVersion}" testCompile "junit:junit:${junitVersion}" testCompile "de.flapdoodle.embed:de.flapdoodle.embed.mongo:${embedMongoVersion}" } To begin with, here’s the document that we will be storing in Mongo. package com.yohanliyanage.blog.mongoit.model; import org.springframework.data.mongodb.core.index.Indexed; import org.springframework.data.mongodb.core.mapping.Document; /** * A Sample Document. * * @author Yohan Liyanage * */ @Document public class Sample { @Indexed private String key; private String value; public Sample(String key, String value) { super(); this.key = key; this.value = value; } public String getKey() { return key; } public void setKey(String key) { this.key = key; } public String getValue() { return value; } public void setValue(String value) { this.value = value; } } To assist with storing and managing this document, let’s write up a simple Repository implementation. The Repository Interface is as follows. package com.yohanliyanage.blog.mongoit.repository; import java.util.List; import com.yohanliyanage.blog.mongoit.model.Sample; /** * Sample Repository API. * * @author Yohan Liyanage * */ public interface SampleRepository { /** * Persists the given Sample. * @param sample */ void save(Sample sample); /** * Returns the list of samples with given key. * @param sample * @return */ List findByKey(String key); } And the implementation… package com.yohanliyanage.blog.mongoit.repository; import java.util.List; import static org.springframework.data.mongodb.core.query.Query.query; import static org.springframework.data.mongodb.core.query.Criteria.*; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.data.mongodb.core.MongoOperations; import org.springframework.stereotype.Repository; import com.yohanliyanage.blog.mongoit.model.Sample; /** * Sample Repository MongoDB Implementation. * * @author Yohan Liyanage * */ @Repository public class SampleRepositoryMongoImpl implements SampleRepository { @Autowired private MongoOperations mongoOps; /** * {@inheritDoc} */ public void save(Sample sample) { mongoOps.save(sample); } /** * {@inheritDoc} */ public List findByKey(String key) { return mongoOps.find(query(where("key").is(key)), Sample.class); } /** * Sets the MongoOps implementation. * * @param mongoOps the mongoOps to set */ public void setMongoOps(MongoOperations mongoOps) { this.mongoOps = mongoOps; } } To wire this up, we need a Spring Bean Configuration. Note that we do not need this for testing. But for the sake of completion, I have included this. The XML configuration is as follows. And now we are ready to write the Integration Test for our Repository Implementation using Embed Mongo. Ideally, the integration tests should be placed in a separate source directory, just like we place our unit tests (ex. src/test/java => src/integration-test/java). However, neither Maven nor Gradle supports this out of the box (yet – v1.2. For Gradle, there’s an on going discussion for this facility). Nevertheless, both Maven and Gradle are flexible, so you can configure the POM / build.gradle to handle this. However, to keep this discussion simple and focused, I will be placing the Integration Tests in the ‘src/test/java’, but I do not recommend this for a real application. Let’s start writing up the Integration Test. First, let’s begin with a simple JUnit based Test for the methods. package com.yohanliyanage.blog.mongoit.repository; import static org.junit.Assert.fail; import org.junit.After; import org.junit.Before; import org.junit.Test; /** * Integration Test for {@link SampleRepositoryMongoImpl}. * * @author Yohan Liyanage */ public class SampleRepositoryMongoImplIntegrationTest { private SampleRepositoryMongoImpl repoImpl; @Before public void setUp() throws Exception { repoImpl = new SampleRepositoryMongoImpl(); } @After public void tearDown() throws Exception { } @Test public void testSave() { fail("Not yet implemented"); } @Test public void testFindByKey() { fail("Not yet implemented"); } } When this JUnit Test Case initializes, we need to fire up EmbedMongo to start an embedded Mongo server. Also, when the Test Case ends, we need to cleanup the DB. The below code snippet does this. package com.yohanliyanage.blog.mongoit.repository; import static org.junit.Assert.fail; import java.io.IOException; import org.junit.*; import org.springframework.data.mongodb.core.MongoTemplate; import com.mongodb.Mongo; import com.yohanliyanage.blog.mongoit.model.Sample; import de.flapdoodle.embed.mongo.MongodExecutable; import de.flapdoodle.embed.mongo.MongodProcess; import de.flapdoodle.embed.mongo.MongodStarter; import de.flapdoodle.embed.mongo.config.MongodConfig; import de.flapdoodle.embed.mongo.config.RuntimeConfig; import de.flapdoodle.embed.mongo.distribution.Version; import de.flapdoodle.embed.process.extract.UserTempNaming; /** * Integration Test for {@link SampleRepositoryMongoImpl}. * * @author Yohan Liyanage */ public class SampleRepositoryMongoImplIntegrationTest { private static final String LOCALHOST = "127.0.0.1"; private static final String DB_NAME = "itest"; private static final int MONGO_TEST_PORT = 27028; private SampleRepositoryMongoImpl repoImpl; private static MongodProcess mongoProcess; private static Mongo mongo; private MongoTemplate template; @BeforeClass public static void initializeDB() throws IOException { RuntimeConfig config = new RuntimeConfig(); config.setExecutableNaming(new UserTempNaming()); MongodStarter starter = MongodStarter.getInstance(config); MongodExecutable mongoExecutable = starter.prepare(new MongodConfig(Version.V2_2_0, MONGO_TEST_PORT, false)); mongoProcess = mongoExecutable.start(); mongo = new Mongo(LOCALHOST, MONGO_TEST_PORT); mongo.getDB(DB_NAME); } @AfterClass public static void shutdownDB() throws InterruptedException { mongo.close(); mongoProcess.stop(); } @Before public void setUp() throws Exception { repoImpl = new SampleRepositoryMongoImpl(); template = new MongoTemplate(mongo, DB_NAME); repoImpl.setMongoOps(template); } @After public void tearDown() throws Exception { template.dropCollection(Sample.class); } @Test public void testSave() { fail("Not yet implemented"); } @Test public void testFindByKey() { fail("Not yet implemented"); } } The initializeDB() method is annotated with @BeforeClass to start this before test case beings. This method fires up an embedded MongoDB instance which is bound to the given port, and exposes a Mongo object which is set to use the given database. Internally, EmbedMongo creates the necessary data files in temporary directories. When this method executes for the first time, EmbedMongo will download the necessary Mongo implementation (denoted by Version.V2_2_0 in above code) if it does not exist already. This is a nice facility specially when it comes to Continuous Integration servers. You don’t have to manually setup Mongo in each of the CI servers. That’s one less external dependency for the tests. In the shutdownDB() method, which is annotated with @AfterClass, we stop the EmbedMongo process. This triggers the necessary cleanups in EmbedMongo to remove the temporary data files, restoring the state to where it was before Test Case was executed. We have now updated setUp() method to build a Spring MongoTemplate object which is backed by the Mongo instance exposed by EmbedMongo, and to setup our RepoImpl with that template. The tearDown() method is updated to drop the ‘Sample’ collection to ensure that each of our test methods start with a clean state. Now it’s just a matter of writing the actual test methods. Let’s start with the save method test. @Test public void testSave() { Sample sample = new Sample("TEST", "2"); repoImpl.save(sample); int samplesInCollection = template.findAll(Sample.class).size(); assertEquals("Only 1 Sample should exist collection, but there are " + samplesInCollection, 1, samplesInCollection); } We create a Sample object, pass it to repoImpl.save(), and assert to make sure that there’s only one Sample in the Sample collection. Simple, straight-forward stuff. And here’s the test method for findByKey method. @Test public void testFindByKey() { // Setup Test Data List samples = Arrays.asList( new Sample("TEST", "1"), new Sample("TEST", "25"), new Sample("TEST2", "66"), new Sample("TEST2", "99")); for (Sample sample : samples) { template.save(sample); } // Execute Test List matches = repoImpl.findByKey("TEST"); // Note: Since our test data (populateDummies) have only 2 // records with key "TEST", this should be 2 assertEquals("Expected only two samples with key TEST, but there are " + matches.size(), 2, matches.size()); } Initially, we setup the data by adding a set of Sample objects into the data store. It’s important that we directly use template.save() here, because repoImpl.save() is a method under-test. We are not testing that here, so we use the underlying “trusted” template.save() during data setup. This is a basic concept in Unit / Integration testing. Then we execute the method under test ‘findByKey’, and assert to ensure that only two Samples matched our query. Likewise, we can continue to write more tests for each of the repository methods, including negative tests. And here’s the final Integration Test file. package com.yohanliyanage.blog.mongoit.repository; import static org.junit.Assert.*; import java.io.IOException; import java.util.Arrays; import java.util.List; import org.junit.*; import org.springframework.data.mongodb.core.MongoTemplate; import com.mongodb.Mongo; import com.yohanliyanage.blog.mongoit.model.Sample; import de.flapdoodle.embed.mongo.MongodExecutable; import de.flapdoodle.embed.mongo.MongodProcess; import de.flapdoodle.embed.mongo.MongodStarter; import de.flapdoodle.embed.mongo.config.MongodConfig; import de.flapdoodle.embed.mongo.config.RuntimeConfig; import de.flapdoodle.embed.mongo.distribution.Version; import de.flapdoodle.embed.process.extract.UserTempNaming; /** * Integration Test for {@link SampleRepositoryMongoImpl}. * * @author Yohan Liyanage */ public class SampleRepositoryMongoImplIntegrationTest { private static final String LOCALHOST = "127.0.0.1"; private static final String DB_NAME = "itest"; private static final int MONGO_TEST_PORT = 27028; private SampleRepositoryMongoImpl repoImpl; private static MongodProcess mongoProcess; private static Mongo mongo; private MongoTemplate template; @BeforeClass public static void initializeDB() throws IOException { RuntimeConfig config = new RuntimeConfig(); config.setExecutableNaming(new UserTempNaming()); MongodStarter starter = MongodStarter.getInstance(config); MongodExecutable mongoExecutable = starter.prepare(new MongodConfig(Version.V2_2_0, MONGO_TEST_PORT, false)); mongoProcess = mongoExecutable.start(); mongo = new Mongo(LOCALHOST, MONGO_TEST_PORT); mongo.getDB(DB_NAME); } @AfterClass public static void shutdownDB() throws InterruptedException { mongo.close(); mongoProcess.stop(); } @Before public void setUp() throws Exception { repoImpl = new SampleRepositoryMongoImpl(); template = new MongoTemplate(mongo, DB_NAME); repoImpl.setMongoOps(template); } @After public void tearDown() throws Exception { template.dropCollection(Sample.class); } @Test public void testSave() { Sample sample = new Sample("TEST", "2"); repoImpl.save(sample); int samplesInCollection = template.findAll(Sample.class).size(); assertEquals("Only 1 Sample should exist in collection, but there are " + samplesInCollection, 1, samplesInCollection); } @Test public void testFindByKey() { // Setup Test Data List samples = Arrays.asList( new Sample("TEST", "1"), new Sample("TEST", "25"), new Sample("TEST2", "66"), new Sample("TEST2", "99")); for (Sample sample : samples) { template.save(sample); } // Execute Test List matches = repoImpl.findByKey("TEST"); // Note: Since our test data (populateDummies) have only 2 // records with key "TEST", this should be 2 assertEquals("Expected only two samples with key TEST, but there are " + matches.size(), 2, matches.size()); } } On a side note, one of the key concerns with Integration Tests is the execution time. We all want to keep our test execution times as low as possible, ideally a couple of seconds to make sure that we can run all the tests during CI, with minimal build and verification times. However, since Integration Tests rely on underlying infrastructure, usually Integration Tests take time to run. But with EmbedMongo, this is not the case. In my machine, above test suite runs in 1.8 seconds, and each test method takes only .166 seconds max. See the screenshot below. I have uploaded the code for above project into GitHub. You can download / clone it from here: https://github.com/yohanliyanage/blog-mongo-integration-tests. For more information regarding EmbedMongo, refer to their site at GitHub https://github.com/flapdoodle-oss/embedmongo.flapdoodle.de.
November 11, 2012
by Yohan Liyanage
· 26,665 Views
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Control Bus Pattern with Spring Integration and JMS
for people in hurry, refer the steps and the demo . introduction control bus pattern is a enterprise integration pattern is used to control distributed systems in spring integration . in this blog, i will show you how a control bus can control your application or a component to start or stop listening to jms message . in this example, we are using jms queue to start and stop the jms inbound-channel-adapter , we can also do this with jdbc inbound-channel-adapter and control this thru an external application. the other way to do the same is by using mbean as in this example . in this use case, there is a spring integration flow. this spring integration flow can be controlled by sending start / stop message to inbound-channel-adapter from a activemq jms queue. details control bus with spring integration control bus spring integration jms to start implementing this use case, we write the junit test 1st. if you notice once the inboundadapter is started the message is received from the adapteroutchannel. once the inboundadapter is stopped no message is received. this is demonstrated as below, @test public void democontrolbus() { assertnull(adapteroutputchanel.receive(1000)); controlchannel.send(new genericmessage("@inboundadapter.start()")); assertnotnull(adapteroutputchanel.receive(1000)); controlchannel.send(new genericmessage("@inboundadapter.stop()")); assertnull(adapteroutputchanel.receive(1000)); } the test configuration looks as below, if you run the “mvn test” the tests work. in the main configuration, we will be configuring actual queues and jms inbound-channel-adapter as below, now when you start the component as “run on server” in sts ide and post a message on myqueue, you can see the subscribers received the messages on the console. you can issue “@inboundadapter.stop()” on the controlbusqueue, it will stop the inbound-channel-adapter, it will also throw java.lang.interruptedexception, it looks like a false alarm. to test if the inbound-channel-adapter is stopped, post a message on to myqueue, the component will not process the message. now issue “@inboundadapter.start()” on the controlbusqueue, it will process the earlier message and start listening for new messages. conclusion if you notice in this blog, we can control the component to listen to message using control bus. the other way to do the same is by using mbean as in this example .
November 8, 2012
by Krishna Prasad
· 13,899 Views
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Spring AOP in Security - Controlling Creation of UI Components via Aspects
The following post will show how in one of the projects that I took part in we used Spring's AOP to introduce some security related functionalities. The concept was such that in order for the user to see some UI components he needed to have a certain level of security privillages. If that requirement was not met then the UIComponent was not presented. Let's take a look at the project structure: Then there were also the aopApplicationContext.xml : Now let's take a look at the most interesting lines of the Spring's application context. First we have all the required schemas - I don't think that this needs to be explained in more depth. Then we have: which enables the @AspectJ support. Next there is the first we are turning on Spring configuration via annotations. Then deliberatly we exclude aspects from being initialized as beans by Spring itself. Why? Because... we want to create the aspect by ourselves and provide the factory-method="aspectOf" . By doing so our aspect will be included in the autowiring process of our beans - thus all the fields annotated with the @Autowired annotation will get the beans injected. Now let's move on to the code: UserServiceImpl.java package pl.grzejszczak.marcin.aop.service; import org.springframework.stereotype.Service; import pl.grzejszczak.marcin.aop.type.Role; import pl.grzejszczak.marcin.aop.user.UserHolder; @Service public class UserServiceImpl implements UserService { private UserHolder userHolder; @Override public UserHolder getCurrentUser() { return userHolder; } @Override public void setCurrentUser(UserHolder userHolder) { this.userHolder = userHolder; } @Override public Role getUserRole() { if (userHolder == null) { return null; } return userHolder.getUserRole(); } } The class UserServiceImpl is immitating a service that would get the current user information from the db or from the current application context. UserHolder.java package pl.grzejszczak.marcin.aop.user; import pl.grzejszczak.marcin.aop.type.Role; public class UserHolder { private Role userRole; public UserHolder(Role userRole) { this.userRole = userRole; } public Role getUserRole() { return userRole; } public void setUserRole(Role userRole) { this.userRole = userRole; } } This is a simple holder class that holds information about current user Role. Role.java package pl.grzejszczak.marcin.aop.type; public enum Role { ADMIN("ADM"), WRITER("WRT"), GUEST("GST"); private String name; private Role(String name) { this.name = name; } public static Role getRoleByName(String name) { for (Role role : Role.values()) { if (role.name.equals(name)) { return role; } } throw new IllegalArgumentException("No such role exists [" + name + "]"); } public String getName() { return this.name; } @Override public String toString() { return name; } } Role is an enum that defines a role for a person being an Admin, Writer or a Guest. UIComponent.java package pl.grzejszczak.marcin.aop.ui; public abstract class UIComponent { protected String componentName; protected String getComponentName() { return componentName; } } An abstraction over concrete implementations of some UI components. SomeComponentForAdminAndGuest.java package pl.grzejszczak.marcin.aop.ui; import pl.grzejszczak.marcin.aop.annotation.SecurityAnnotation; import pl.grzejszczak.marcin.aop.type.Role; @SecurityAnnotation(allowedRole = { Role.ADMIN, Role.GUEST }) public class SomeComponentForAdminAndGuest extends UIComponent { public SomeComponentForAdminAndGuest() { this.componentName = "SomeComponentForAdmin"; } public static UIComponent getComponent() { return new SomeComponentForAdminAndGuest(); } } This component is an example of a UI component extention that can be seen only by users who have roles of Admin or Guest. SecurityAnnotation.java package pl.grzejszczak.marcin.aop.annotation; import java.lang.annotation.Retention; import java.lang.annotation.RetentionPolicy; import pl.grzejszczak.marcin.aop.type.Role; @Retention(RetentionPolicy.RUNTIME) public @interface SecurityAnnotation { Role[] allowedRole(); } Annotation that defines a roles that can have this component created. UIFactoryImpl.java package pl.grzejszczak.marcin.aop.ui; import org.apache.commons.lang.NullArgumentException; import org.springframework.stereotype.Component; @Component public class UIFactoryImpl implements UIFactory { @Override public UIComponent createComponent(Class componentClass) throws Exception { if (componentClass == null) { throw new NullArgumentException("Provide class for the component"); } return (UIComponent) Class.forName(componentClass.getName()).newInstance(); } } A factory class that given the class of an object that extends UIComponent returns a new instance of the given UIComponent. SecurityInterceptor.java package pl.grzejszczak.marcin.aop.interceptor; import java.lang.annotation.Annotation; import java.lang.reflect.AnnotatedElement; import java.util.Arrays; import java.util.List; import org.aspectj.lang.ProceedingJoinPoint; import org.aspectj.lang.annotation.Around; import org.aspectj.lang.annotation.Aspect; import org.aspectj.lang.annotation.Pointcut; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import org.springframework.beans.factory.annotation.Autowired; import pl.grzejszczak.marcin.aop.annotation.SecurityAnnotation; import pl.grzejszczak.marcin.aop.service.UserService; import pl.grzejszczak.marcin.aop.type.Role; import pl.grzejszczak.marcin.aop.ui.UIComponent; @Aspect public class SecurityInterceptor { private static final Logger LOGGER = LoggerFactory.getLogger(SecurityInterceptor.class); public SecurityInterceptor() { LOGGER.debug("Security Interceptor created"); } @Autowired private UserService userService; @Pointcut("execution(pl.grzejszczak.marcin.aop.ui.UIComponent pl.grzejszczak.marcin.aop.ui.UIFactory.createComponent(..))") private void getComponent(ProceedingJoinPoint thisJoinPoint) { } @Around("getComponent(thisJoinPoint)") public UIComponent checkSecurity(ProceedingJoinPoint thisJoinPoint) throws Throwable { LOGGER.info("Intercepting creation of a component"); Object[] arguments = thisJoinPoint.getArgs(); if (arguments.length == 0) { return null; } Annotation annotation = checkTheAnnotation(arguments); boolean securityAnnotationPresent = (annotation != null); if (securityAnnotationPresent) { boolean userHasRole = verifyRole(annotation); if (!userHasRole) { LOGGER.info("Current user doesn't have permission to have this component created"); return null; } } LOGGER.info("Current user has required permissions for creating a component"); return (UIComponent) thisJoinPoint.proceed(); } /** * Basing on the method's argument check if the class is annotataed with * {@link SecurityAnnotation} * * @param arguments * @return */ private Annotation checkTheAnnotation(Object[] arguments) { Object concreteClass = arguments[0]; LOGGER.info("Argument's class - [{}]", new Object[] { arguments }); AnnotatedElement annotatedElement = (AnnotatedElement) concreteClass; Annotation annotation = annotatedElement.getAnnotation(SecurityAnnotation.class); LOGGER.info("Annotation present - [{}]", new Object[] { annotation }); return annotation; } /** * The function verifies if the current user has sufficient privilages to * have the component built * * @param annotation * @return */ private boolean verifyRole(Annotation annotation) { LOGGER.info("Security annotation is present so checking if the user can use it"); SecurityAnnotation annotationRule = (SecurityAnnotation) annotation; List requiredRolesList = Arrays.asList(annotationRule.allowedRole()); Role userRole = userService.getUserRole(); return requiredRolesList.contains(userRole); } } This is the aspect defined at the pointcut of executing a function createComponent of the UIFactory interface. Inside the Around advice there is the logic that first checks what kind of an argument has been passed to the method createComponent (for example SomeComponentForAdminAndGuest.class). Next it is checking if this class is annotated with SecurityAnnotation and if that is the case it checks what kind of Roles are required to have the component created. Afterwards it checks if the current user (from UserService to UserHolder's Roles) has the required role to present the component. If that is the case thisJoinPoint.proceed() is called which in effect returns the object of the class that extends UIComponent. Now let's test it - here comes the SpringJUnit4ClassRunner AopTest.java package pl.grzejszczak.marcin.aop; import org.junit.Assert; import org.junit.Test; import org.junit.runner.RunWith; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.test.context.ContextConfiguration; import org.springframework.test.context.junit4.SpringJUnit4ClassRunner; import pl.grzejszczak.marcin.aop.service.UserService; import pl.grzejszczak.marcin.aop.type.Role; import pl.grzejszczak.marcin.aop.ui.SomeComponentForAdmin; import pl.grzejszczak.marcin.aop.ui.SomeComponentForAdminAndGuest; import pl.grzejszczak.marcin.aop.ui.SomeComponentForGuest; import pl.grzejszczak.marcin.aop.ui.SomeComponentForWriter; import pl.grzejszczak.marcin.aop.ui.UIFactory; import pl.grzejszczak.marcin.aop.user.UserHolder; @RunWith(SpringJUnit4ClassRunner.class) @ContextConfiguration(locations = { "classpath:aopApplicationContext.xml" }) public class AopTest { @Autowired private UIFactory uiFactory; @Autowired private UserService userService; @Test public void adminTest() throws Exception { userService.setCurrentUser(new UserHolder(Role.ADMIN)); Assert.assertNotNull(uiFactory.createComponent(SomeComponentForAdmin.class)); Assert.assertNotNull(uiFactory.createComponent(SomeComponentForAdminAndGuest.class)); Assert.assertNull(uiFactory.createComponent(SomeComponentForGuest.class)); Assert.assertNull(uiFactory.createComponent(SomeComponentForWriter.class)); } } And the logs: pl.grzejszczak.marcin.aop.interceptor.SecurityInterceptor:26 Security Interceptor created pl.grzejszczak.marcin.aop.interceptor.SecurityInterceptor:38 Intercepting creation of a component pl.grzejszczak.marcin.aop.interceptor.SecurityInterceptor:48 Argument's class - [[class pl.grzejszczak.marcin.aop.ui.SomeComponentForAdmin]] pl.grzejszczak.marcin.aop.interceptor.SecurityInterceptor:54 Annotation present - [@pl.grzejszczak.marcin.aop.annotation.SecurityAnnotation(allowedRole=[ADM])] pl.grzejszczak.marcin.aop.interceptor.SecurityInterceptor:57 Security annotation is present so checking if the user can use it pl.grzejszczak.marcin.aop.interceptor.SecurityInterceptor:70 Current user has required permissions for creating a component pl.grzejszczak.marcin.aop.interceptor.SecurityInterceptor:38 Intercepting creation of a component pl.grzejszczak.marcin.aop.interceptor.SecurityInterceptor:48 Argument's class - [[class pl.grzejszczak.marcin.aop.ui.SomeComponentForAdminAndGuest]] pl.grzejszczak.marcin.aop.interceptor.SecurityInterceptor:54 Annotation present - [@pl.grzejszczak.marcin.aop.annotation.SecurityAnnotation(allowedRole=[ADM, GST])] pl.grzejszczak.marcin.aop.interceptor.SecurityInterceptor:57 Security annotation is present so checking if the user can use it pl.grzejszczak.marcin.aop.interceptor.SecurityInterceptor:70 Current user has required permissions for creating a component pl.grzejszczak.marcin.aop.interceptor.SecurityInterceptor:38 Intercepting creation of a component pl.grzejszczak.marcin.aop.interceptor.SecurityInterceptor:48 Argument's class - [[class pl.grzejszczak.marcin.aop.ui.SomeComponentForGuest]] pl.grzejszczak.marcin.aop.interceptor.SecurityInterceptor:54 Annotation present - [@pl.grzejszczak.marcin.aop.annotation.SecurityAnnotation(allowedRole=[GST])] pl.grzejszczak.marcin.aop.interceptor.SecurityInterceptor:57 Security annotation is present so checking if the user can use it pl.grzejszczak.marcin.aop.interceptor.SecurityInterceptor:66 Current user doesn't have permission to have this component created pl.grzejszczak.marcin.aop.interceptor.SecurityInterceptor:38 Intercepting creation of a component pl.grzejszczak.marcin.aop.interceptor.SecurityInterceptor:48 Argument's class - [[class pl.grzejszczak.marcin.aop.ui.SomeComponentForWriter]] pl.grzejszczak.marcin.aop.interceptor.SecurityInterceptor:54 Annotation present - [@pl.grzejszczak.marcin.aop.annotation.SecurityAnnotation(allowedRole=[WRT])] pl.grzejszczak.marcin.aop.interceptor.SecurityInterceptor:57 Security annotation is present so checking if the user can use it pl.grzejszczak.marcin.aop.interceptor.SecurityInterceptor:66 Current user doesn't have permission to have this component created The unit test shows that for given Admin role only first two components get created whereas for the two others nulls are returned (due to the fact that user doesn't have proper rights). That is how in our project we used Spring's AOP to create a simple framework that would check if the user can have the given component created or not. Thanks to this after having programmed the aspects one doesn't have to remember about writing any security related code since it will be done for him. If you have any suggestions related to this post please feel free to comment it :)
November 7, 2012
by Marcin Grzejszczak
· 25,905 Views · 2 Likes
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Using Spock to Test Spring Classes
As the previous post mentioned, Spock is a powerful DSL built on Groovy ideal for TDD and BDD testing and this post will describe how easy it is to use Spock to test Spring classes, in this case the CustomerService class from the post Using Spring Data to access MongoDB. It will also cover using Spock for mocking. Spock relies heavily on the Spring's TestContext framework and does this via the @ContextConfiguration annotation. This allows the test specification class to load an application context from one or more locations. This will then allow the test specification to access beans either via the annotation @Autowired or @Resource. The test below shows how an injected CusotmerService instance can be tested using Spock and the Spring TestContext: (This is a slightly contrived example as to properly unit test the CustomerService class as you would create a CustomerService class in the test as opposed to one created and injected by Spring.) package com.city81.mongodb.springdata.dao import org.springframework.beans.factory.annotation.Autowired import org.springframework.test.context.ContextConfiguration import spock.lang.* import com.city81.mongodb.springdata.entity.Account import com.city81.mongodb.springdata.entity.Address import com.city81.mongodb.springdata.entity.Customer @ContextConfiguration(locations = "classpath:spring/applicationContext.xml") class CustomerServiceTest extends Specification { @Autowired CustomerService customerService def setup() { customerService.dropCustomerCollection() } def "insert customer"() { setup: // setup test class args Address address = new Address() address.setNumber("81") address.setStreet("Mongo Street") address.setTown("City") address.setPostcode("CT81 1DB") Account account = new Account() account.setAccountName("Personal Account") List accounts = new ArrayList() accounts.add(account) Customer customer = new Customer() customer.setAddress(address) customer.setName("Mr Bank Customer") customer.setAccounts(accounts) when: customerService.insertCustomer(customer) then: def customers = customerService.findAllCustomers() customers.size == 1 customers.get(0).name == "Mr Bank Customer" customers.get(0).address.street == "Mongo Street" } } The problem though with the above test is that MongoDB needs to be up and running so to remove this dependency we can Mock out the interaction the database. Spock's mocking framework provides many of the features you'd find in similar frameworks like Mockito. The enhanced CustomerServiceTest mocks the CustomerRepository and sets the mocked object on the CustomerService. package com.city81.mongodb.springdata.dao import org.springframework.beans.factory.annotation.Autowired import org.springframework.test.context.ContextConfiguration import spock.lang.* import com.city81.mongodb.springdata.entity.Account import com.city81.mongodb.springdata.entity.Address import com.city81.mongodb.springdata.entity.Customer @ContextConfiguration(locations = "classpath:spring/applicationContext.xml") class CustomerServiceTest extends Specification { @Autowired CustomerService customerService CustomerRepository customerRepository = Mock() def setup() { customerService.customerRepository = customerRepository customerService.dropCustomerCollection() } def "insert customer"() { setup: // setup test class args Address address = new Address() address.setNumber("81") address.setStreet("Mongo Street") address.setTown("City") address.setPostcode("CT81 1DB") Account account = new Account() account.setAccountName("Personal Account") List accounts = new ArrayList() accounts.add(account) Customer customer = new Customer() customer.setAddress(address) customer.setName("Mr Bank Customer") customer.setAccounts(accounts) when: customerService.insertCustomer(customer) then: 1 * customerRepository.save(customer) } def "find all customers"() { setup: // setup test class args Address address = new Address() address.setStreet("Mongo Street") Customer customer = new Customer() customer.setAddress(address) customer.setName("Mr Bank Customer") // setup mocking def mockCustomers = [] mockCustomers << customer customerRepository.findAll() >> mockCustomers when: def customers = customerService.findAllCustomers() then: customers.size() == 1 customers.get(0).name == "Mr Bank Customer" } } The CustomerRepository is by way of name and type although it could be inferred by just the name eg def customerRepository = Mock(CustomerRepository) The injected customerRepository is overwritten by the mocked instance and then in the test setup, functionality can be mocked. In the then block of the insert customer feature, the number of interactions with the save method of customerRepository is tested and in the find all customers feature, the return list of customers from the findAll call is a mocked List,as opposed to one retrieved from the database. More detail on Spock's mocking capabilities can be found on the project's home page.
October 23, 2012
by Geraint Jones
· 48,960 Views · 1 Like
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XA Transactions (2 Phase Commit): A Simple Guide
Explaining the details of XA transactions and use of XA Transactions in Spring framework.
October 22, 2012
by Yusuf Aytaş
· 227,472 Views · 12 Likes
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From API Key to User with ASP.NET Web API
ASP.NET Web API is a great tool to build an API with. Or as my buddy Kristof Rennen (and the French) always say: “it makes you ‘api”. One of the things I like a lot is the fact that you can do very powerful things that you know and love from the ASP.NET MVC stack, like, for example, using filter attributes. Action filters, result filters and… authorization filters. Say you wanted to protect your API and make use of the controller’s User property to return user-specific information. You probably will add an [Authorize] attribute (to ensure the user is authenticated) to either the entire API controller or to one of its action methods, like this: [Authorize] public class SuperSecretController : ApiController { public string Get() { return string.Format("Hello, {0}", User.Identity.Name); } } Great! But how will your application know who’s calling? Forms authentication doesn’t really make sense for a lot of API’s. Configuring IIS and switching to Windows authentication or basic authentication may be an option. But not every ASP.NET Web API will live in IIS, right? And maybe you want to use some other form of authentication for your API, for example one that uses a custom HTTP header containing an API key? Let’s see how you can do that… Our API authentication? An API key API keys may make sense for your API. They provide an easy means of authenticating your API consumers based on a simple token that is passed around in a custom header. OAuth2 may make sense as well, but even that one boils down to a custom Authorization header at the HTTP level. (hint: the approach outlined in this post can be used for OAuth2 tokens as well) Let’s build our API and require every API consumer to pass in a custom header, named “X-ApiKey”. Calls to our API will look like this: GET http://localhost:60573/api/v1/SuperSecret HTTP/1.1 Host: localhost:60573 X-ApiKey: 12345 In our SuperSecretController above, we want to make sure that we’re working with a traditional IPrincipal which we can query for username, roles and possibly even claims if needed. How do we get that identity there? Translating the API key using a DelegatingHandler The title already gives you a pointer. We want to add a plugin into ASP.NET Web API’s pipeline which replaces the current thread’s IPrincipal with one that is mapped from the incoming API key. That plugin will come in the form of a DelegatingHandler, a class that’s plugged in really early in the ASP.NET Web API pipeline. I’m not going to elaborate on what DelegatingHandler does and where it fits, there’s a perfect post on that to be found here. Our handler, which I’ll call AuthorizationHeaderHandler will be inheriting ASP.NET Web API’s DelegatingHandler. The method we’re interested in is SendAsync, which will be called on every request into our API. public class AuthorizationHeaderHandler : DelegatingHandler { protected override Task SendAsync( HttpRequestMessage request, CancellationToken cancellationToken) { // ... } } This method offers access to the HttpRequestMessage, which contains everything you’ll probably be needing such as… HTTP headers! Let’s read out our X-ApiKey header, convert it to a ClaimsIdentity (so we can add additional claims if needed) and assign it to the current thread: public class AuthorizationHeaderHandler : DelegatingHandler { protected override Task SendAsync( HttpRequestMessage request, CancellationToken cancellationToken) { IEnumerable apiKeyHeaderValues = null; if (request.Headers.TryGetValues("X-ApiKey", out apiKeyHeaderValues)) { var apiKeyHeaderValue = apiKeyHeaderValues.First(); // ... your authentication logic here ... var username = (apiKeyHeaderValue == "12345" ? "Maarten" : "OtherUser"); var usernameClaim = new Claim(ClaimTypes.Name, username); var identity = new ClaimsIdentity(new[] {usernameClaim}, "ApiKey"); var principal = new ClaimsPrincipal(identity); Thread.CurrentPrincipal = principal; } return base.SendAsync(request, cancellationToken); } } Easy, no? The only thing left to do is registering this handler in the pipeline during your application’s start: GlobalConfiguration.Configuration.MessageHandlers.Add(new AuthorizationHeaderHandler()); From now on, any request coming in with the X-ApiKey header will be translated into an IPrincipal which you can easily use throughout your web API. Enjoy! PS: if you’re looking into OAuth2, I’ve used a similar approach in “ASP.NET Web API OAuth2 delegation with Windows Azure Access Control Service” to handle OAuth2 tokens.
October 19, 2012
by Maarten Balliauw
· 43,988 Views · 1 Like
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Implementing Repository Pattern with Entity Framework
When working with Entity Framework - Code First model approach, a developer creates POCO entities for database tables. The benefit of using Code First model is to have POCO entity for each table that can be used as either WCF Data Contracts or you can apply your own custom attributes to handle Security, Logging, etc. and there is no mapping needed as we used to do in Entity Framework (Model First) approach if the application architecture is n-tier based. Considering the Data Access layer, we will implement a repository pattern that encapsulates the persistence logic in a separate class. This class will be responsible to perform database operations. Let’s suppose the application is based on n-tier architecture and having 3 tiers namely Presentation, Business and Data Access. Common library contains all our POCO entities that will be used by all the layers. Presentation Layer: Contains Views, Forms Business Layer: Managers that handle logic functionality Data Access Layer: Contains Repository class that handles CRUD operations Common Library: Contain POCO entities. We will implement an interface named “IRepository” that defines the signature of all the appropriate generic methods needed to perform CRUD operation and then implement the Repository class that defines the actual implementation of each method. We can also instantiate Repository object using Dependency Injection or apply Factory pattern. Code Snippet: IRepository public interface IRepository : IDisposable { /// /// Gets all objects from database /// /// IQueryable All() where T : class; /// /// Gets objects from database by filter. /// /// Specified a filter /// IQueryable Filter(Expression> predicate) where T : class; /// /// Gets objects from database with filting and paging. /// /// /// Specified a filter /// Returns the total records count of the filter. /// Specified the page index. /// Specified the page size /// IQueryable Filter(Expression> filter, out int total, int index = 0, int size = 50) where T : class; /// /// Gets the object(s) is exists in database by specified filter. /// /// Specified the filter expression /// bool Contains(Expression> predicate) where T : class; /// /// Find object by keys. /// /// Specified the search keys. /// T Find(params object[] keys) where T : class; /// /// Find object by specified expression. /// /// /// T Find(Expression> predicate) where T : class; /// /// Create a new object to database. /// /// Specified a new object to create. /// T Create(T t) where T : class; /// /// Delete the object from database. /// /// Specified a existing object to delete. int Delete(T t) where T : class; /// /// Delete objects from database by specified filter expression. /// /// /// int Delete(Expression> predicate) where T : class; /// /// Update object changes and save to database. /// /// Specified the object to save. /// int Update(T t) where T : class; /// /// Select Single Item by specified expression. /// /// /// /// T Single(Expression> expression) where T : class; void SaveChanges(); void ExecuteProcedure(String procedureCommand, params SqlParameter[] sqlParams); } Code Snippet: Repository public class Repository : IRepository { DbContext Context; public Repository() { Context = new DBContext(); } public Repository(DBContext context) { Context = context; } public void CommitChanges() { Context.SaveChanges(); } public T Single(Expression> expression) where T : class { return All().FirstOrDefault(expression); } public IQueryable All() where T : class { return Context.Set().AsQueryable(); } public virtual IQueryable Filter(Expression> predicate) where T : class { return Context.Set().Where(predicate).AsQueryable(); } public virtual IQueryable Filter(Expression> filter, out int total, int index = 0, int size = 50) where T : class { int skipCount = index * size; var _resetSet = filter != null ? Context.Set().Where(filter).AsQueryable() : Context.Set().AsQueryable(); _resetSet = skipCount == 0 ? _resetSet.Take(size) : _resetSet.Skip(skipCount).Take(size); total = _resetSet.Count(); return _resetSet.AsQueryable(); } public virtual T Create(T TObject) where T : class { var newEntry = Context.Set().Add(TObject); Context.SaveChanges(); return newEntry; } public virtual int Delete(T TObject) where T : class { Context.Set().Remove(TObject); return Context.SaveChanges(); } public virtual int Update(T TObject) where T : class { try { var entry = Context.Entry(TObject); Context.Set().Attach(TObject); entry.State = EntityState.Modified; return Context.SaveChanges(); } catch (OptimisticConcurrencyException ex) { throw ex; } } public virtual int Delete(Expression> predicate) where T : class { var objects = Filter(predicate); foreach (var obj in objects) Context.Set().Remove(obj); return Context.SaveChanges(); } public bool Contains(Expression> predicate) where T : class { return Context.Set().Count(predicate) > 0; } public virtual T Find(params object[] keys) where T : class { return (T)Context.Set().Find(keys); } public virtual T Find(Expression> predicate) where T : class { return Context.Set().FirstOrDefault(predicate); } public virtual void ExecuteProcedure(String procedureCommand, params SqlParameter[] sqlParams){ Context.Database.ExecuteSqlCommand(procedureCommand, sqlParams); } public virtual void SaveChanges() { Context.SaveChanges(); } public void Dispose() { if (Context != null) Context.Dispose(); } } The benefit of using Repository pattern is that all the database operations will be managed centrally and in future if you want to change the underlying database connector you can add another Repository class and defines its own implementation or change the existing one.
October 13, 2012
by Ovais Mehboob Ahmed Khan
· 31,984 Views
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Redis pub/sub Using Spring
Continuing to discover the powerful set of Redis features, the one worth mentioning about is out of the box support of pub/sub messaging. Pub/Sub messaging is essential part of many software architectures. Some software systems demand from messaging solution to provide high-performance, scalability, queues persistence and durability, fail-over support, transactions, and many more nice-to-have features, which in Java world mostly always leads to using one of JMS implementation providers. In my previous projects I have actively used Apache ActiveMQ (now moving towards Apache ActiveMQ Apollo). Though it's a great implementation, sometimes I just needed simple queuing support and Apache ActiveMQ just looked overcomplicated for that. Alternatives? Please welcome Redis pub/sub! If you are already using Redis as key/value store, few additional lines of configuration will bring pub/sub messaging to your application in no time. Spring Data Redis project abstracts very well Redis pub/sub API and provides the model so familiar to everyone who uses Spring capabilities to integrate with JMS. As always, let's start with the POM configuration file. It's pretty small and simple, includes necessary Spring dependencies, Spring Data Redis and Jedis, great Java client for Redis. 4.0.0 com.example.spring redis 0.0.1-SNAPSHOT jar UTF-8 3.1.1.RELEASE org.springframework.data spring-data-redis 1.0.1.RELEASE cglib cglib-nodep 2.2 log4j log4j 1.2.16 redis.clients jedis 2.0.0 jar org.springframework spring-core ${spring.version} org.springframework spring-context ${spring.version} org.apache.maven.plugins maven-compiler-plugin 2.3.2 1.6 1.6 Moving on to configuring Spring context, let's understand what we need to have in order for a publisher to publish some messages and for a consumer to consume them. Knowing the respective Spring abstractions for JMS will help a lot with that. we need connection factory -> JedisConnectionFactory we need a template for publisher to publish messages -> RedisTemplate we need a message listener for consumer to consume messages -> RedisMessageListenerContainer Using Spring Java configuration, let's describe our context: package com.example.redis.config; import org.springframework.context.annotation.Bean; import org.springframework.context.annotation.Configuration; import org.springframework.data.redis.connection.jedis.JedisConnectionFactory; import org.springframework.data.redis.core.RedisTemplate; import org.springframework.data.redis.listener.ChannelTopic; import org.springframework.data.redis.listener.RedisMessageListenerContainer; import org.springframework.data.redis.listener.adapter.MessageListenerAdapter; import org.springframework.data.redis.serializer.GenericToStringSerializer; import org.springframework.data.redis.serializer.StringRedisSerializer; import org.springframework.scheduling.annotation.EnableScheduling; import com.example.redis.IRedisPublisher; import com.example.redis.impl.RedisMessageListener; import com.example.redis.impl.RedisPublisherImpl; @Configuration @EnableScheduling public class AppConfig { @Bean JedisConnectionFactory jedisConnectionFactory() { return new JedisConnectionFactory(); } @Bean RedisTemplate< String, Object > redisTemplate() { final RedisTemplate< String, Object > template = new RedisTemplate< String, Object >(); template.setConnectionFactory( jedisConnectionFactory() ); template.setKeySerializer( new StringRedisSerializer() ); template.setHashValueSerializer( new GenericToStringSerializer< Object >( Object.class ) ); template.setValueSerializer( new GenericToStringSerializer< Object >( Object.class ) ); return template; } @Bean MessageListenerAdapter messageListener() { return new MessageListenerAdapter( new RedisMessageListener() ); } @Bean RedisMessageListenerContainer redisContainer() { final RedisMessageListenerContainer container = new RedisMessageListenerContainer(); container.setConnectionFactory( jedisConnectionFactory() ); container.addMessageListener( messageListener(), topic() ); return container; } @Bean IRedisPublisher redisPublisher() { return new RedisPublisherImpl( redisTemplate(), topic() ); } @Bean ChannelTopic topic() { return new ChannelTopic( "pubsub:queue" ); } } Very easy and straightforward. The presence of @EnableScheduling annotation is not necessary and is required only for our publisher implementation: the publisher will publish a string message every 100 ms. package com.example.redis.impl; import java.util.concurrent.atomic.AtomicLong; import org.springframework.data.redis.core.RedisTemplate; import org.springframework.data.redis.listener.ChannelTopic; import org.springframework.scheduling.annotation.Scheduled; import com.example.redis.IRedisPublisher; public class RedisPublisherImpl implements IRedisPublisher { private final RedisTemplate< String, Object > template; private final ChannelTopic topic; private final AtomicLong counter = new AtomicLong( 0 ); public RedisPublisherImpl( final RedisTemplate< String, Object > template, final ChannelTopic topic ) { this.template = template; this.topic = topic; } @Scheduled( fixedDelay = 100 ) public void publish() { template.convertAndSend( topic.getTopic(), "Message " + counter.incrementAndGet() + ", " + Thread.currentThread().getName() ); } } And finally our message listener implementation (which just prints message on a console). package com.example.redis.impl; import org.springframework.data.redis.connection.Message; import org.springframework.data.redis.connection.MessageListener; public class RedisMessageListener implements MessageListener { @Override public void onMessage( final Message message, final byte[] pattern ) { System.out.println( "Message received: " + message.toString() ); } } Awesome, just two small classes, one configuration to wire things together and we have full pub/sub messaging support in our application! Let's run the application as standalone ... package com.example.redis; import org.springframework.context.ApplicationContext; import org.springframework.context.annotation.AnnotationConfigApplicationContext; import com.example.redis.config.AppConfig; public class RedisPubSubStarter { public static void main(String[] args) { new AnnotationConfigApplicationContext( AppConfig.class ); } } ... and see following output in a console: ... Message received: Message 1, pool-1-thread-1 Message received: Message 2, pool-1-thread-1 Message received: Message 3, pool-1-thread-1 Message received: Message 4, pool-1-thread-1 Message received: Message 5, pool-1-thread-1 Message received: Message 6, pool-1-thread-1 Message received: Message 7, pool-1-thread-1 Message received: Message 8, pool-1-thread-1 Message received: Message 9, pool-1-thread-1 Message received: Message 10, pool-1-thread-1 Message received: Message 11, pool-1-thread-1 Message received: Message 12, pool-1-thread-1 Message received: Message 13, pool-1-thread-1 Message received: Message 14, pool-1-thread-1 Message received: Message 15, pool-1-thread-1 Message received: Message 16, pool-1-thread-1 ... Great! There is much more which you could do with Redis pub/sub, excellent documentation is available for you on Redis official web site.
October 13, 2012
by Andriy Redko
· 43,044 Views · 4 Likes
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Eventing with Spring Framework
Spring Framework, since it’s inception, included an eventing mechanism which can be used for application-wide eventing. This eventing mechanism was developed to be used internally by Spring Framework for eventing, such as notification of context being refreshed, etc, but it can be used for application specific custom events as well. This eventing API is based on an interface named org.springframework.context.ApplicationListener, which defined one method named onApplicationEvent. Below code snippet shows a simple events listener which just logs the event information. package com.yohanliyanage.blog.springevents; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import org.springframework.context.ApplicationEvent; import org.springframework.context.ApplicationListener; public class MyEventListener implements ApplicationListener { private static final Log LOG = LogFactory.getLog(MyEventListener.class); public void onApplicationEvent(ApplicationEvent event) { LOG.info("Event Occurred : " + event); } } To register this event listener, all that we have to do is to add it as a Spring managed bean. If we just add it as a bean in Spring Bean Configuration XML, or if we have annotation scanning enabled, adding an annotation such as @Component, would ensure that our listener will receive events via Spring. Below XML block shows the simple bean definition in XML for registering this listener. < ?xml version="1.0" encoding="UTF-8"?> Now, to test this code, let’s write up a main method which creates the Spring Application Context. In this code, it’s assumed that the Spring bean definition file is located at META-INF/spring/application-context.xml, which is in class path. You can download the sample code here. public class Main { public static void main(String[] args) throws InterruptedException { ApplicationContext context = new ClassPathXmlApplicationContext("classpath:META-INF/spring/application-context.xml"); } } When we run this, we get the following output. 18:45:00 INFO Refreshing org.springframework.context.support.ClassPathXmlApplicationContext@7a982589: startup date [Sun Sep 30 18:45:00 IST 2012]; root of context hierarchy 18:45:00 INFO Loading XML bean definitions from class path resource [META-INF/spring/application-context.xml] 18:45:00 INFO Pre-instantiating singletons in org.springframework.beans.factory.support.DefaultListableBeanFactory@33e228bc: defining beans [com.yohanliyanage.blog.springevents.MyEventListener#0]; root of factory hierarchy 18:45:00 INFO Event Occurred : org.springframework.context.event.ContextRefreshedEvent[source=org.springframework.context.support.ClassPathXmlApplicationContext@7a982589: startup date [Sun Sep 30 18:45:00 IST 2012]; root of context hierarchy] As highlighted above, our listener gets notified by the framework when Spring Context is refreshed during initialization. This is a framework event, and of course, there’s no magic to it. But how can we generate application specific, custom events? As you will see in the blow code block, this is also very simple and straight-forward. First, let’s create our own event implementation. For this, we just have to write a class that extends from ApplicationEvent. package com.yohanliyanage.blog.springevents; import org.springframework.context.ApplicationEvent; public class MyCustomEvent extends ApplicationEvent { private static final long serialVersionUID = -5308299518665062983L; public MyCustomEvent(Object source) { super(source); } } Next, we have to write a class which does the event publishing. In order to publish an event, we need to get a reference to ApplicationEventPublisher. This can be easily done by implementing the ApplicationEventPublisherAware, as shown in the code block below. package com.yohanliyanage.blog.springevents; import org.springframework.context.ApplicationEventPublisher; import org.springframework.context.ApplicationEventPublisherAware; public class MyEventPublisher implements ApplicationEventPublisherAware { private ApplicationEventPublisher publisher; public void setApplicationEventPublisher(ApplicationEventPublisher publisher) { this.publisher = publisher; } public void publish() { this.publisher.publishEvent(new MyCustomEvent(this)); } } Now, this bean also should be added to the Spring bean configuration, as follows. Note that you do not have to write a separate publisher class in your application. Your existing Spring beans can easily to this by just implementing the ApplicationEventPublisherAware interface. Now, let’s slightly modify the Main class to invoke the publish() method in our event publisher. public static void main(String[] args) throws InterruptedException { ApplicationContext context = new ClassPathXmlApplicationContext("classpath:META-INF/spring/application-context.xml"); MyEventPublisher publisher = context.getBean(MyEventPublisher.class); publisher.publish(); } When we run the application now, we get the following output. 19:21:18 INFO Refreshing org.springframework.context.support.ClassPathXmlApplicationContext@7a982589: startup date [Sun Sep 30 19:21:18 IST 2012]; root of context hierarchy 19:21:18 INFO Loading XML bean definitions from class path resource [META-INF/spring/application-context.xml] 19:21:19 INFO Pre-instantiating singletons in org.springframework.beans.factory.support.DefaultListableBeanFactory@2565a3c2: defining beans [com.yohanliyanage.blog.springevents.MyEventListener#0,com.yohanliyanage.blog.springevents.MyEventPublisher#0]; root of factory hierarchy 19:21:19 INFO Event Occurred : org.springframework.context.event.ContextRefreshedEvent[source=org.springframework.context.support.ClassPathXmlApplicationContext@7a982589: startup date [Sun Sep 30 19:21:18 IST 2012]; root of context hierarchy] 19:21:19 INFO Event Occurred : com.yohanliyanage.blog.springevents.MyCustomEvent[source=com.yohanliyanage.blog.springevents.MyEventPublisher@5a676437] As highlighted above, our custom event has been triggered, and our listener was able to handle that event. So far, so good. But if you have noticed, our listener gets invoked for all of the events that occurs in the application, including framework events. But in most of the cases, this is not desirable. The listener will be interested in one or more specific events. Up until Spring 3.0, this eventing mechanism did not had support for filtering events. That is, if you implement an ApplicationListener, you would end up receiving all events that occurs in the application, and you had to manually look into the ApplicationEvent object that gets passed in to your listener to identify and discard events that you are not interested in. This of course, was a hassle, and probably due to this, Spring Eventing did not get attention of most of the developers. With Spring 3.0, this API was enhanced with Generics support, to provide filtering of events. Now, the ApplicationListener interface is parameterized as follows. public interface ApplicationListener < E extends ApplicationEvent > extends EventListener The onApplicationEvent method parameter uses generic type E. With this, we can implement our listener as follows. package com.yohanliyanage.blog.springevents; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import org.springframework.context.ApplicationListener; public class MyEventListener implements ApplicationListener < MyCustomEvent > { private static final Log LOG = LogFactory.getLog(MyEventListener.class); public void onApplicationEvent(MyCustomEvent event) { LOG.info("Event Occurred : " + event); } } This listener implementation’s onApplicationEvent method will be called only for MyCustomEvent based events. This in turn provides the necessary event filtering, where we don’t have to write boilerplate code to discard unnecessary events. The log output is as follows. 19:29:31 INFO Refreshing org.springframework.context.support.ClassPathXmlApplicationContext@7a982589: startup date [Sun Sep 30 19:29:31 IST 2012]; root of context hierarchy 19:29:31 INFO Loading XML bean definitions from class path resource [META-INF/spring/application-context.xml] 19:29:31 INFO Pre-instantiating singletons in org.springframework.beans.factory.support.DefaultListableBeanFactory@2565a3c2: defining beans [com.yohanliyanage.blog.springevents.MyEventListener#0,com.yohanliyanage.blog.springevents.MyEventPublisher#0]; root of factory hierarchy 19:29:31 INFO Event Occurred : com.yohanliyanage.blog.springevents.MyCustomEvent[source=com.yohanliyanage.blog.springevents.MyEventPublisher@5a676437] As seen above in the output, we no longer receive the unwanted framework specific events, or any other events that we are not interested in. So in conclusion, Spring does provide a decent eventing mechanism which is quite useful for implementing eventing support in applications. While this has been around since the early days of Spring, it did not see wide adoption primarily due to it’s incapability of filtering out specific events for a listener. But with Spring 3.0, things are improved, and now it has reached a state where we can leverage it to broadcast events in our applications with ease. One thing to note is that by default, Spring Eventing is synchronous. But this can be made asynchronous by providing a custom ApplicationEventMulticaster implementation that would make use of a TaskExecutor. Download Source Code – Spring Eventing Example Project
October 12, 2012
by Yohan Liyanage
· 38,809 Views · 5 Likes
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