this tutorial will walk you through how to setup ibatis ( mybatis ) in a simple java project and will present how to work with stored procedures using mysql.the goal os this tutorial is to demonstrate how to execute/call stored procedures using ibatis/ mybatis . pre-requisites for this tutorial i am using: ide: eclipse (you can use your favorite one) database: mysql libs/jars: mybatis , mysql conector and junit (for testing) this is how your project should look like: sample database please run the script into your database before getting started with the project implementation. you will find the script (with dummy data) inside the sql folder. as we are going to work with stored procedures, you will also have to execute a script with procedures. here are the procedures: use `blog_ibatis`;drop procedure if exists `gettotalcity`;delimiter $$use `blog_ibatis`$$create procedure `blog_ibatis`.`gettotalcity` (out total integer)begin select count(*) into total from city;end$$delimiter ; -- -------------------------------------------------------------------------------- use `blog_ibatis`;drop procedure if exists `gettotalcitystateid`;delimiter $$use `blog_ibatis`$$create procedure `blog_ibatis`.`gettotalcitystateid` (in stateid smallint, out total integer)begin select count(*) into total from city where state_id = stateid;end$$delimiter ; -- -------------------------------------------------------------------------------- use `blog_ibatis`;drop procedure if exists `getstates`;delimiter $$use `blog_ibatis`$$create procedure `blog_ibatis`.`getstates` ()begin select state_id, state_code, state_name from state;end$$delimiter ; 1 – spmapper – xml i did not find anything on the user manual about how to call stored procedures, so i decided to search on the mailing list. and i found some tips of how to call stores procedures. on the previous version, ibatis has a special xml tag for stored procedures. but there is no xml tag for it on current mybatis version (version 3). to call a stored procedure usgin mybatis/ibatis 3 you will have to follow some tips: must set the statement type to callable must use the jdbc standard escape sequence for stored procedures: { call xxx (parm1, parm2) } must set the mode of all parameters ( in, out, inout ) all in, out, and inout parameters must be a part of the parametertype or parametermap (discouraged). the only exception is if you are using a map as a parameter object. in that case you do not need to add out parameters to the map before calling , mybatis will add them for you automatically. resulttype or resultmap (more typically) is only used if the procedure returns a result set. important : oracle ref cursors are usually returned as parameters, not directly from the stored proc. so with ref cursors, resultmap and/or resulttype is usually not used. first example: we want to call the procedure gettotalcity and this procedure only have one out parameter, and no in/inout parameter. how to do it? we are going to ser inline parameters in this first example. to use inline parameters, create a pojo class to represent your parameters, set the parametertype to the class you created and you are going to use this notation to represent each parameter: #{parametername, mode=out, jdbctype=integer} mode can be in, out, inout and specify the jdbctype of your parameter to create the mybatis xml configuration, you can use the select ou update tag. do not forget to set the statementtype to callable . here is how our mybatis statement is going to look like: { call gettotalcity(#{total, mode=out, jdbctype=integer})} and this is the pojo class which represents the parameter for gettotalcity procedure: package com.loiane.model; public class param { private int total; public int gettotal() { return total; } public void settotal(int total) { this.total = total; } second example: now we are going to try to call the same stored procedure we demonstrated on the first example, but we are going to use a parametermap, like you used to do in version 2.x. a very important note: this is discouraged, please use inline parameters. let’s declare the param pojo class as a parametermap: and the stored procedure statment: { call gettotalcity(?) } note that now we use “ ? ” (question mark) to represent each parameter. third example: now we are going to call a stored procedure with in and out parameters. let’s follow the same rules as the fisrt example. we are going to use inline parameters and we are going to create a pojo class to represent our parameter. mybatis code: { call gettotalcitystateid( #{stateid, mode=in, jdbctype=integer}, #{total, mode=out, jdbctype=integer})} param2 pojo: package com.loiane.model; public class param2 { private int total; private int stateid; public int gettotal() { return total; } public void settotal(int total) { this.total = total; } public int getstateid() { return stateid; } public void setstateid(int stateid) { this.stateid = stateid; } fourth example: now let’s try to retrieve a resultset from the stored procedure. for this we are going to use a resultmap. { call getstates()} state pojo class: package com.loiane.model; public class state { private int id; private string code; private string name; public int getid() { return id; } public void setid(int id) { this.id = id; } public string getcode() { return code; } public void setcode(string code) { this.code = code; } public string getname() { return name; } public void setname(string name) { this.name = name; } 2- spmapper – annotations now let’s try to do the same thing we did using xml config. annotation for first example (xml): @select(value= "{ call gettotalcity( #{total, mode=out, jdbctype=integer} )}")@options(statementtype = statementtype.callable)object callgettotalcityannotations(param param); it is very similiar to a simple select statement, but we have to set the statement type to callable. to do it, we can use the annotation @options . with annotations, we can only use inline parameters, so we will not be able to represent the second exemple using annotations. annotation for third example (xml): the explanation is the same as first example, i am just going to list the code: @select(value= "{ call gettotalcitystateid( #{stateid, mode=in, jdbctype=integer}, #{total, mode=out, jdbctype=integer})}")@options(statementtype = statementtype.callable)object callgettotalcitystateidannotations(param2 param2); annotation for fourth example (xml): i tried to set the fourth example with annotation, but the only thing i’ve got is this: //todo: set resultmap with annotations/*@select(value= "{ call gettotalcitystateid()}")@options(statementtype = statementtype.callable)/*@results(value = { @result(property="id", column="state_id"), @result(property="name", column="state_name"), @result(property="code", column="state_code"),})*/list callgetstatesannotations(); and it does not work. i tried to search on the mailing list, no luck. i could not find a way to represent a resultmap with annotation and stored procedures. i don’t know if it is a limitation. if you have any clue how to do it, please leave a comment, i will appreciate it! download if you want to download the complete sample project, you can get it from my github account: https://github.com/loiane/ibatis-stored-procedures if you want to download the zip file of the project, just click on download: there are more articles about ibatis to come. stay tooned! from http://loianegroner.com/2011/03/ibatis-mybatis-working-with-stored-procedures/

I’ve written a couple of posts (here and here) about Java and the JDBC Driver for SQL Server with the promise of eventually writing about how to get a Java application running on the Windows Azure platform. In this post, I’ll deliver on that promise. Specifically, I’ll show you two things: 1) how to connect to a SQL Azure Database from a Java application running locally, and 2) how to connect to a SQL Azure database from an application running in Windows Azure. You should consider these as two ordered steps in moving an application from running locally against SQL Server to running in Windows Azure against SQL Azure. In both steps, connection to SQL Azure relies on the JDBC Driver for SQL Server and SQL Azure. The instructions below assume that you already have a Windows Azure subscription. If you don’t already have one, you can create one here: http://www.microsoft.com/windowsazure/offers/. (You’ll need a Windows Live ID to sign up.) I chose the Free Trial Introductory Special, which allows me to get started for free as long as keep my usage limited. (This is a limited offer. For complete pricing details, see http://www.microsoft.com/windowsazure/pricing/.) After you purchase your subscription, you will have to activate it before you can begin using it (activation instructions will be provided in an email after signing up). Connecting to SQL Azure from an application running locally I’m going to assume you already have an application running locally and that it uses the JDBC Driver for SQL Server. If that isn’t the case, then you can start from scratch by following the steps in this post: Getting Started with the SQL Server JDBC Driver. Once you have an application running locally, then the process for running that application with a SQL Azure back-end requires two steps: 1. Migrate your database to SQL Azure. This only takes a couple of minutes (depending on the size of your database) with the SQL Azure Migration Wizard - follow the steps in the Creating a SQL Azure Server and Creating a SQL Azure Database sections of this post. 2. Change the database connection string in your application. Once you have moved your local database to SQL Azure, you only have to change the connection string in your application to use SQL Azure as your data store. In my case (using the Northwind database), this meant changing this… String connectionUrl = "jdbc:sqlserver://serverName\\sqlexpress;" + "database=Northwind;" + "user=UserName;" + "password=Password"; …to this… String connectionUrl = "jdbc:sqlserver://xxxxxxxxxx.database.windows.net;" + "database=Northwind;" + "user=UserName@xxxxxxxxxx;" + "password=Password"; (where xxxxxxxxxx is your SQL Azure server ID). Connecting to SQL Azure from an application running in Windows Azure The heading for this section might be a bit misleading. Once you have a locally running application that is using SQL Azure, then all you have to do is move your application to Windows Azure. The connecting part is easy (see above), but moving your Java application to Windows Azure takes a bit more work. Fortunately, Ben Lobaugh has written a great post that that shows how to use the Windows Azure Starter Kit for Java to get a Java application (a JSP application, actually) running in Windows Azure: Deploying a Java application to Windows Azure with Command-Line Ant. (If you are using Eclipse, see Ben’s related post: Deploying a Java application to Windows Azure with Eclipse.) I won’t repeat his work here, but I will call out the steps I took in modifying his instructions to deploy a simple JSP page that connects to SQL Azure. 1. Add the JDBC Driver for SQL Server to the Java archive. One step in Ben’s tutorial (see the Select the Java Runtime Environment section) requires that you create a .zip file from your local Java installation and add it to your Java/Azure application. Most likely, your local Java installation references the JDBC driver by setting the classpath environment variable. When you create a .zip file from your java installation, the JDBC driver will not be included and the classpath variable will not be set in the Azure environment. I found the easiest way around this was to simply add the sqljdbc4.jar file (probably located in C:\Program Files\Microsoft SQL Server JDBC Driver\sqljdbc_3.0\enu) to the \lib\ext directory of my local Java installation before creating the .zip file. Note: You can put the JDBC driver in a separate directory, include it when you create the .zip folder, and set the classpath environment variable in the startup.bat script. But, I found the above approach to be easier. 2. Modify the JSP page. Instead of the code Ben suggests for the HelloWorld.jsp file (see the Prepare your Java Application section), use code from your locally running application. In my case, I just used the code from this post after changing the connection string and making a couple minor JSP-specific changes: Northwind Customers That’s it!. To summarize the steps… Migrate your database to SQL Azure with the SQL Azure Migration Wizard. Change the database connection in your locally running application. Use the Windows Azure Starter Kit for Java to move your application to Windows Azure. (You’ll need to follow instructions in this post and instructions above.) Thanks. -Brian

This article discusses dependency injection in a tutorial format. It covers some of the features of CDI such as type safe annotations configuration, alternatives and more.

this tutorial will walk you through how to setup ibatis ( mybatis ) in a simple java project and will present how to work with dynamic queries (sql). pre-requisites for this tutorial i am using: ide: eclipse (you can use your favorite one) database: mysql libs/jars: mybatis , mysql conector and junit (for testing) this is how your project should look like: sample database please run the script into your database before getting started with the project implementation. you will find the script (with dummy data) inside the sql folder. 1 – article pojo i represented the pojo we are going to use in this tutorial with a uml diagram, but you can download the complete source code in the end of this article. the goal of this tutorial is to demonstrate how to retrieve the article information from database using dynamic sql to filter the data. 2 – article mapper – xml one of the most powerful features of mybatis has always been its dynamic sql capabilities. if you have any experience with jdbc or any similar framework, you understand how painful it is to conditionally concatenate strings of sql together, making sure not to forget spaces or to omit a comma at the end of a list of columns. dynamic sql can be downright painful to deal with. while working with dynamic sql will never be a party, mybatis certainly improves the situation with a powerful dynamic sql language that can be used within any mapped sql statement. the dynamic sql elements should be familiar to anyone who has used jstl or any similar xml based text processors. in previous versions of mybatis, there were a lot of elements to know and understand. mybatis 3 greatly improves upon this, and now there are less than half of those elements to work with. mybatis employs powerful ognl based expressions to eliminate most of the other elements. if choose (when, otherwise) trim (where, set) foreach let’s explain each one with examples. 1 – first scenario : we want to retrieve all the articles from database with an optional filter: title. in other words, if user specify an article title, we are going to retrieve the articles that match with the title, otherwise we are going to retrieve all the articles from database. so we are going to implement a condition (if) : select id, title, author from article where id_status = 1 and title like #{title} 2 – second scenario : now we have two optional filters: article title and author. the user can specify both, none or only one filter. so we are going to implement two conditions: select id, title, author from article where id_status = 1 and title like #{title} and author like #{author} 3 – third scenario : now we want to give the user only one option: the user will have to specify only one of the following filters: title, author or retrieve all the articles from ibatis category. so we are going to use a choose element: select id, title, author from article where id_status = 1 and title like #{title} and author like #{author} and id_category = 3 4 – fourth scenario : take a look at all three statements above. they all have a condition in common: where id_status = 1. it means we are already filtering the active articles let’s remove this condition to make it more interesting. select id, title, author from article where title like #{title} and author like #{author} what if both title and author are null? we are going to have the following statement: select id, title, authorfrom articlewhere and what if only the author is not null? we are going to have the fololwing statement: select id, title, authorfrom articlewhereand author like #{author} and both fails! how to fix it? 5 – fifth scenario : we want to retrieve all the articles with two optional filters: title and author. to avoid the 4th scenatio, we are going to use a where element: select id, title, author from article title like #{title} and author like #{author} mybatis has a simple answer that will likely work in 90% of the cases. and in cases where it doesn’t, you can customize it so that it does. the where element knows to only insert “where” if there is any content returned by the containing tags. furthermore, if that content begins with “and” or “or”, it knows to strip it off. if the where element does not behave exactly as you like, you can customize it by defining your own trim element. for example,the trim equivalent to the where element is: select id, title, author from article title like #{title} and author like #{author} the overrides attribute takes a pipe delimited list of text to override, where whitespace is relevant. the result is the removal of anything specified in the overrides attribute, and the insertion of anything in the with attribute. you can also use the trim element with set. 6 – sixth scenario : the user will choose all the categories an article can belong to. so in this case, we have a list (a collection), and we have to interate this collection and we are going to use a foreach element: select id, title, author from article title like #{title} and author like #{author} the foreach element is very powerful, and allows you to specify a collection, declare item and index variables that can be used inside the body of the element. it also allows you to specify opening and closing strings, and add a separator to place in between iterations. the element is smart in that it won’t accidentally append extra separators. note : you can pass a list instance or an array to mybatis as a parameter object. when you do, mybatis will automatically wrap it in a map, and key it by name. list instances will be keyed to the name “list” and array instances will be keyed to the name “array”. the complete article.xml file looks like this: select id, title, author from article where id_status = 1 and title like #{title} select id, title, author from article where id_status = 1 and title like #{title} and author like #{author} select id, title, author from article where id_status = 1 and title like #{title} and author like #{author} and id_category = 3 select id, title, author from article title like #{title} and author like #{author} select id, title, author from article title like #{title} and author like #{author} select id, title, author from article where id_category in #{category} download if you want to download the complete sample project, you can get it from my github account: https://github.com/loiane/ibatis-dynamic-sql if you want to download the zip file of the project, just click on download: there are more articles about ibatis to come. stay tooned! happy coding! from http://loianegroner.com/2011/03/ibatis-mybatis-working-with-dynamic-queries-sql/

This tutorial will walk you through how to setup iBatis (MyBatis) in a simple Java project and will present an example using a discriminator column, in another words it is a inheritance mapping tutorial. Pre-Requisites For this tutorial I am using: IDE: Eclipse (you can use your favorite one) DataBase: MySQL Libs/jars: Mybatis, MySQL conector and JUnit (for testing) This is how your project should look like: Sample Database Please run the script into your database before getting started with the project implementation. You will find the script (with dummy data) inside the sql folder. 1 – POJOs – Beans I represented the beans here with a UML model, but you can download the complete source code in the end of this article. As you can see on the Data Modeling Diagram and the UML diagram above, we have a class Employee and two subclasses: Developer and Manager. The goal of this tutorial is to retrieve all the Employees from the database, but these employees can be an instance of Developer or Manager, and we are going to use a discriminator column to see which class we are going to instanciate. 2 – Employee Mapper – XML Sometimes a single database query might return result sets of many different (but hopefully somewhat related) data types. The discriminator element was designed to deal with this situation, and others, including class inheritance hierarchies. The discriminator is pretty simple to understand, as it behaves much like a switch statement in Java. A discriminator definition specifies column and javaType attributes. The column is where MyBatis will look for the value to compare. The javaType is required to ensure the proper kind of equality test is performed (although String would probably work for almost any situation). SELECT id, name, employee_type, manager_id, info, developer_id, product FROM employee E left join manager M on M.employee_id = E.id left join developer D on D.employee_id = E.id In this example, MyBatis would retrieve each record from the result set and compare its employee type value. If it matches any of the discriminator cases, then it will use the resultMap specified by the case. This is done exclusively, so in other words, the rest of the resultMap is ignored (unless it is extended, which we talk about in a second). If none of the cases match, then MyBatis simply uses the resultMap as defined outside of the discriminator block. So, if the managerResult was declared as follows: Now all of the properties from both the managerResult and developerResult will be loaded. Once again though, some may find this external definition of maps somewhat tedious. Thereforethere’s an alternative syntax for those that prefer a more concise mapping style. For example: SELECT id, name, employee_type, manager_id, info, developer_id, product FROM employee E left join manager M on M.employee_id = E.id left join developer D on D.employee_id = E.id Remember that these are all Result Maps, and if you don’t specify any results at all, then MyBatis willautomatically match up columns and properties for you. So most of these examples are more verbosethan they really need to be. That said, most databases are kind of complex and it’s unlikely that we’ll beable to depend on that for all cases. 3 - Employee Mapper – Annotations We did the configuration in XML, now let’s try to use annotations to do the same thing we did using XML. This is the code for EmployeeMapper.java: package com.loiane.data; import java.util.List; import org.apache.ibatis.annotations.Case;import org.apache.ibatis.annotations.Result;import org.apache.ibatis.annotations.Select;import org.apache.ibatis.annotations.TypeDiscriminator; import com.loiane.model.Developer;import com.loiane.model.Employee;import com.loiane.model.Manager; public interface EmployeeMapper { final String SELECT_EMPLOYEE = "SELECT id, name, employee_type, manager_id, info, developer_id, product " + "FROM employee E left join manager M on M.employee_id = E.id " + "left join developer D on D.employee_id = E.id "; /** * Returns the list of all Employee instances from the database. * @return the list of all Employee instances from the database. */ @Select(SELECT_EMPLOYEE) @TypeDiscriminator(column = "employee_type", cases = { @Case (value="1", type = Manager.class, results={ @Result(property="managerId", column="manager_id"), @Result(property="info"), }), @Case (value="2", type = Developer.class, results={ @Result(property="developerId", column="developer_id"), @Result(property="project", column="product"), }) }) List getAllEmployeesAnnotation();} If you are reading this blog lately, you are already familiar with the @Select and @Result annotations. So let’s skip it. Let’s talk about the @TypeDiscriminator and @Case annotations. @TypeDiscriminator A group of value cases that can be used to determine the result mapping to perform. Attributes: column, javaType, jdbcType, typeHandler, cases. The cases attribute is an array of Cases. @Case A single case of a value and its corresponding mappings. Attributes: value, type, results. The results attribute is an array of Results, thus this Case Annotation is similar to an actual ResultMap, specified by the Results annotation below. In this example: We set the column atribute for @TypeDiscriminator to determine which column MyBatis will look for the value to compare. And we set an array of @Case. For each @Case we set the value, so if the column matches the value, MyBatis will instanciate a object of type we set and we also set an array of @Result to match column with class atribute. Note one thing: using XML we set the id and name properties. We did not set these properties using annotations. It is not necessary, because the column matches the atribute name. But if you need to set, it is going to look like this: @Select(SELECT_EMPLOYEE)@Results(value = { @Result(property="id"), @Result(property="name")})@TypeDiscriminator(column = "employee_type", cases = { @Case (value="1", type = Manager.class, results={ @Result(property="managerId", column="manager_id"), @Result(property="info"), }), @Case (value="2", type = Developer.class, results={ @Result(property="developerId", column="developer_id"), @Result(property="project", column="product"), })})List getAllEmployeesAnnotation(); 4 – EmployeeDAO In the DAO, we have two methods: the first one will call the select statement from the XML and the second one will call the annotation method. Both returns the same result. package com.loiane.dao; import java.util.List; import org.apache.ibatis.session.SqlSession;import org.apache.ibatis.session.SqlSessionFactory; import com.loiane.data.EmployeeMapper;import com.loiane.model.Employee; public class EmployeeDAO { /** * Returns the list of all Employee instances from the database. * @return the list of all Employee instances from the database. */ @SuppressWarnings("unchecked") public List selectAll(){ SqlSessionFactory sqlSessionFactory = MyBatisConnectionFactory.getSqlSessionFactory(); SqlSession session = sqlSessionFactory.openSession(); try { List list = session.selectList("Employee.getAllEmployees"); return list; } finally { session.close(); } } /** * Returns the list of all Employee instances from the database. * @return the list of all Employee instances from the database. */ public List selectAllUsingAnnotations(){ SqlSessionFactory sqlSessionFactory = MyBatisConnectionFactory.getSqlSessionFactory(); SqlSession session = sqlSessionFactory.openSession(); try { EmployeeMapper mapper = session.getMapper(EmployeeMapper.class); List list = mapper.getAllEmployeesAnnotation(); return list; } finally { session.close(); } } The output if you call one of these methods and print: Employee ID = 1 Name = Kate Manager ID = 1 Info = info KateEmployee ID = 2 Name = Josh Developer ID = 1 Project = webEmployee ID = 3 Name = Peter Developer ID = 2 Project = desktopEmployee ID = 4 Name = James Manager ID = 2 Info = info JamesEmployee ID = 5 Name = Susan Developer ID = 3 Project = web Download If you want to download the complete sample project, you can get it from my GitHub account: https://github.com/loiane/ibatis-discriminator If you want to download the zip file of the project, just click on download: There are more articles about iBatis to come. Stay tooned! From http://loianegroner.com/2011/03/ibatis-mybatis-discriminator-column-example-inheritance-mapping-tutorial/

this tutorial will walk you through how to setup ibatis ( mybatis ) in a simple java project and will present an example using a class constructor with arguments. pre-requisites for this tutorial i am using: ide: eclipse (you can use your favorite one) database: mysql libs/jars: mybatis , mysql conector and junit (for testing) this is how your project should look like: sample database please run the script into your database before getting started with the project implementation. you will find the script (with dummy data) inside the sql folder. 1 – pojo i represented the beans here with a uml model, but you can download the complete source code in the end of this article. as you can see, we do not have a default construtor in this class, only a constructor with some arguments. some persistence frameworks requires a default constructor, but you have to be careful with your business logic. let’s say there are a couple of mandatory atributes in your class. nothing is going to stop you if you do not set these atributes and try to insert, update on the database. and you problably will get an exception for that. to prevent this kind of situation, you can create a constructor with the mandatory arguments. and ibatis/ mybatis can handle this situation for you, because you do not need to create a default constructor. 2 – blog mapper – xml while properties will work for most data transfer object (dto) type classes, and likely most of yourdomain model, there may be some cases where you want to use immutable classes. often tables thatcontain reference or lookup data that rarely or never changes is suited to immutable classes.constructor injection allows you to set values on a class upon instantiation, without exposing publicmethods. mybatis also supports private properties and private javabeans properties to achieve this, butsome people prefer constructor injection. the constructor element enables this. in order to inject the results into the constructor, mybatis needs to identify the constructor by the type of its parameters. java has no way to introspect (or reflect) on parameter names. so when creating a constructor element, ensure that the arguments are in order, and that the data types are specified. if you need, you can still map another attributes, such as association, collection in your resultmap. following is the blog.xml file: select idblog as id, name, url from blog 3 - blog mapper – annotations we did the configuration in xml, now let’s try to use annotations to do the same thing we did using xml. this is the code for blogmapper.java: package com.loiane.data; import java.util.list; import org.apache.ibatis.annotations.arg; import org.apache.ibatis.annotations.constructorargs; import org.apache.ibatis.annotations.select; import com.loiane.model.blog; public interface blogmapper { /** * returns the list of all blog instances from the database. * @return the list of all blog instances from the database. */ @select("select idblog as id, name, url from blog ") @constructorargs(value = { @arg(column="id",javatype=integer.class), @arg(column="url",javatype=string.class) }) list selectallblogs(); } let’s take a look at the @constructorargs and @arg annotations: @constructorargs collects a group of results to be passed to a result object constructor. attributes: value, which is an array of args. xml equivalent: constructor @arg a single constructor argument that is part of a constructorargs collection. attributes: id, column, javatype, jdbctype, typehandler. the id attribute is a boolean value that identifies the property to be used for comparisons, similar to the xml element. xml equivalent: idarg, arg we do not need to use the @results annotation because the other attributes has the same name, so mybatis knows how to map them. download if you want to download the complete sample project, you can get it from my github account: https://github.com/loiane/ibatis-constructor if you want to download the zip file of the project, just click on download: there are more articles about ibatis to come. stay tooned! happy coding! once again though, some may find this external definition of maps somewhat tedious. thereforethere’s an alternative syntax for those that prefer a more concise mapping style.

There has been a lot of buzz lately on high-availability and clustering. Most developers don't care and why should they? These features should be transparent to the application architecture and not something of concern to the developers of that application. But knowledge never hurts, so I emerged myself into the world of load balancing, heartbeats and virtual IP addresses. And you know what? Next time we need a infrastructure like this, I can at least sit down with the guys from the infrastructure department and at least know what the hell they are talking about. So what exactly is a high-availability clustered infrastructure (HACI, as I'll call it from now on) ? In essence, it should be a zero-downtime infrastructure (or at least perceived as one by the end user, which means never ever returning a default browser 404 page), capable of horizontal scaling when the need for it arises and without a single point of failure. It's the SLA writer's dream. A basic HACI setup looks like this: The users enters through a virtual IP address, assigned to one of the two load balancers. Only one of the load-balancers is active (the active master, LB1), the other one is there in the event LB1 fails ((LB2, a passive slave). The two load balancers are redundant, ie. having the exact same configuration. The load balancers redirect all traffic to the real servers. This can be done through round-robin assignment or through other means like sticky sessions, where the same user is redirected to the same server each and every time within a session. Servers can be added at any moment and configured on the load balancers. Ideally, the load balancer configuration is aware of the hardware specification and balances the load accordingly, but that's beyond the scope of this article (it involves adding weights). If all servers balanced by the load balancer fail, a backup server should be used to redirect all traffic coming from the load balancer. This can be a very lightweight server, which purpose is only to provide a sensible error page to the user (something like 'Sorry, we are performing maintenance'). Again, perception and immediate feedback to the user is key. You don't want to show the user a plain 404 page. Off course, if the backup server goes down too, you're in trouble (off course, by that time, warning bells should have gone off on every level in the hierarchy). So how to achieve this with as little effort as possible? If you want to try this out, I suggest you start by installing a virtual machine like VirtualBox or VMWare. This way you can try out the configuration yourself. In this example, I'll be load-balancing 3 Tomcat servers using sticky sessions using 2 load balancers in active-passive mode. I'm assuming all 3 Tomcat servers share the same hardware configuration, so they are all able to handle the same amount of traffic each. I'm also throwing in a backup server, in case all 3 Tomcat servers go down (serving a custom 503 page kindly informing the user of a catastrophic failure, instead of dropping the standard 404 bomb). You want to start off by assigning IP addresses to the servers. This will make your life a bit easier. We'll need 7 addresses: 3 for the tomcat server, 1 for the backup server, 2 for the loadbalancers and 1 virtual IP address to be shared between the load balancers (and which will be the entry point for your users). So our assignment will be: Virtual IP 10.0.5.99 www.haci.local LB1 10.0.5.100 lb1.haci.local #MASTER LB2 10.0.5.101 lb2.haci.local #SLAVE WEB1 10.0.5.102 web1.haci.local WEB2 10.0.5.103 web2.haci.local WEB3 10.0.5.104 web3.haci.local BACKUP 10.0.5.105 backup.haci.local Setting up the web servers is easy. You just install Tomcat on each server and create a simple JSP file to be served to users (make a small change, like the background color, on each server to distinguish the servers). I won't be covering session replication between the Tomcat servers, as it'll take me too far. If you want, you can configure the appropriate session replication and storage (using multicast or JDBC for example). The backup server I'm using is a basic LAMP server that returns a simple 503 page on every request it gets. The 503 error code is important, because it reflects the current state of the system: currently unavailable. For the loadbalancers I'll be using 2 applications: HAProxy and keepalived. HAProxy is going to handle load balancing, while keepalived will handle the failover between the two load balancers. First, we're going to configure HAProxy for both LB1 and LB2. Installing HAProxy is quite easy on an ubuntu system. Just do a sudo apt-get install haproxy and you're off. After the install, backup the current HAProxy config and start editing away. cp /etc/haproxy.cfg /etc/haproxy.cfg_orig cat /dev/null > /etc/haproxy.cfg vi /etc/haproxy.cfg The content of the config to reflect our setup should become something like this (same config on LB1 and LB2): global log 127.0.0.1 local0 log 127.0.0.1 local1 notice #log loghost local0 info maxconn 4096 #debug #quiet user haproxy group haproxy defaults log global mode http option httplog option dontlognull retries 3 redispatch maxconn 2000 contimeout 5000 clitimeout 50000 srvtimeout 50000 frontend http-in bind 10.0.5.99:80 default_backend servers backend servers mode http stats enable stats auth someuser:somepassword balance roundrobin cookie JSESSIONID prefix option httpclose option forwardfor option httpchk HEAD /check.txt HTTP/1.0 server web1 10.0.5.102:80 cookie haci_web1 check server web2 10.0.5.103:80 cookie haci_web2 check server web3 10.0.5.104:80 cookie haci_web3 check server webbackup 10.0.5.105:80 backup After this, enable HAProxy on both LB1 and LB2 by editing /etc/defaults/haproxy # Set ENABLED to 1 if you want the init script to start haproxy. ENABLED=1 # Add extra flags here. #EXTRAOPTS="-de -m 16" So far for the HAProxy configuration. We can't start it up yet, as LB1 and LB2 aren't listening yet on the virtual IP address. Next we'll configure the failover of the loadbalancers using keepalived. Installing it on Ubuntu is as easy as it was for HAProxy: sudo apt-get install keepalived. But its configuration is slightly different on both load balancers. First, we need to configure the both servers to be able to listen to the shared IP address. Add the following line to /etc/sysctl.conf: net.ipv4.ip_nonlocal_bind=1 And run sysctl -p Now, we configure keepalived so that LB1 is configured as the main load balancer and binds to the shared IP address, while LB2 is on standby, ready to take over whenever LB1 goes down. The configuration for LB1 looks like this (edit /etc/keepalived/keepalived.conf): vrrp_script chk_haproxy { # Requires keepalived-1.1.13 script "killall -0 haproxy" # cheaper than pidof interval 2 # check every 2 seconds weight 2 # add 2 points of prio if OK } vrrp_instance VI_1 { interface eth0 state MASTER virtual_router_id 51 priority 101 # 101 on master, 100 on backup virtual_ipaddress { 10.0.5.99 } track_script { chk_haproxy } } Start up keepalived and check whether it is listening to the virtual IP address. /etc/init.d/keepalived start ip addr sh eth0 It should return something like this, indicating it is listening to the virtual IP address 2: eth0: mtu 1500 qdisc pfifo_fast qlen 1000 link/ether 00:0c:29:a5:5b:93 brd ff:ff:ff:ff:ff:ff inet 10.0.5.100/24 brd 10.0.5.255 scope global eth0 inet 10.0.5.99/32 scope global eth0 inet6 fe80::20c:29ff:fea5:5b93/64 scope link valid_lft forever preferred_lft forever Next, we configure LB2. The configuration is almost the same, exception for the priority. vrrp_script chk_haproxy { # Requires keepalived-1.1.13 script "killall -0 haproxy" # cheaper than pidof interval 2 # check every 2 seconds weight 2 # add 2 points of prio if OK } vrrp_instance VI_1 { interface eth0 state MASTER virtual_router_id 51 priority 100 # 101 on master, 100 on backup virtual_ipaddress { 10.0.5.99 } track_script { chk_haproxy } } Start up keepalived and check the network interface. /etc/init.d/keepalived start ip addr sh eth0 It should return something like this, indicating it is not listening to the virtual IP address 2: eth0: mtu 1500 qdisc pfifo_fast qlen 1000 link/ether 00:0c:29:a5:5b:93 brd ff:ff:ff:ff:ff:ff inet 10.0.5.101/24 brd 10.0.5.255 scope global eth0 inet6 fe80::20c:29ff:fea5:5b93/64 scope link valid_lft forever preferred_lft forever Now, start up HAProxy on both LB1 and LB2. /etc/init.d/haproxy start Now you can issue requests to 10.0.5.99 (or www.haci.local), which will go to LB1, which in turn will load-balance the request to either WEB1, WEB2 and WEB3. You can test the load balancing by turning off WEB1 (or the server you're currently on). You can also the backup server by turning all main webservers (WEB1, WEB2 and WEB3). And you can test the loadbalancer failover by turning off LB1. At that point LB2 will kick in and act as the master, loadbalancing all requests. When you turn LB1 back on, it'll take over the master role once again. HAProxy allows you to add extra servers very easily, reloading the configuration without breaking existing sessions. See the HAProxy documentation for more info or on ServerFault. (http://serverfault.com/questions/165883/is-there-a-way-to-add-more-backend-server-to-haproxy-without-restarting-haproxy). Cheap and effective. While most enterprise shops have hardware load balancers, which also have these possibilities and more, if you're on a tight budget or need to simulate a HACI environment for development purposes (a lesson here: always simulate your production environment when you're testing during development), this might be the sane option. To finish, I'll quickly explain how to set up the backup server (a simple LAMP server). Create a vhost configuration on the apache for www.haci.local or any other domain pointing to the virtual IP address and set up mod_rewrite for it: RewriteEngine On RewriteCond %{REQUEST_URI} !\.(css|gif|ico|jpg|js|png|swf|txt)$ [NC] RewriteConf %{REQUEST_URI} !/503.php RewriteRule .* /503.php [L] Then create the 503.php file and add this to the top of it: Sorry, our servers are currently undergoing maintenance. Please check back with us in a while. Thank you for your patience. You can decorate the 503.php file any way you like. You can even use CSS, JavaScript and image files in the php file. Now, back to my IDE. I'm getting withdrawal symptoms.

Last week, I spent a few hours upgrading AppFuse from JSF 1.2 to JSF 2.0. In reality, I upgraded from MyFaces 1.2.7 to 2.0.4, but all JSF implementations should be the same, right? All in all, it was a pretty easy upgrade with a few minor AppFuse-specific things. My goal in upgrading was to do the bare minimum to get things working and to leave integration of JSF 2 features for a later date. In addition to upgrading MyFaces, I had to upgrade Tomahawk by changing the dependency's artifactId to tomahawk20. I was also able to remove the following listener from my web.xml: org.apache.myfaces.webapp.StartupServletContextListener After that, I discovered that MyFaces uses a new URI (/javax.faces.resource/) for serving up some of its resource files. I kindly asked Spring Security to ignore these requests by adding the following to my security.xml file. Since JSF 2 includes Facelets by default, I tried removing Facelets as a dependency. After doing this, I received the following error: ERROR [308855416@qtp-120902214-7] ViewHandlerWrapper.fillChain(158) | Error instantiation parent Faces ViewHandler java.lang.ClassNotFoundException: com.sun.facelets.FaceletViewHandler at org.codehaus.plexus.classworlds.strategy.SelfFirstStrategy.loadClass(SelfFirstStrategy.java:50) at org.codehaus.plexus.classworlds.realm.ClassRealm.loadClass(ClassRealm.java:244) at org.codehaus.plexus.classworlds.realm.ClassRealm.loadClass(ClassRealm.java:230) at org.mortbay.jetty.webapp.WebAppClassLoader.loadClass(WebAppClassLoader.java:401) at org.mortbay.jetty.webapp.WebAppClassLoader.loadClass(WebAppClassLoader.java:363) at org.ajax4jsf.framework.ViewHandlerWrapper.fillChain(ViewHandlerWrapper.java:144) at org.ajax4jsf.framework.ViewHandlerWrapper.calculateRenderKitId(ViewHandlerWrapper.java:68) at org.apache.myfaces.lifecycle.DefaultRestoreViewSupport.isPostback(DefaultRestoreViewSupport.java:179) at org.apache.myfaces.lifecycle.RestoreViewExecutor.execute(RestoreViewExecutor.java:113) at org.apache.myfaces.lifecycle.LifecycleImpl.executePhase(LifecycleImpl.java:171) at org.apache.myfaces.lifecycle.LifecycleImpl.execute(LifecycleImpl.java:118) at javax.faces.webapp.FacesServlet.service(FacesServlet.java:189) Figuring this was caused by the following element in my web.xml ... org.ajax4jsf.VIEW_HANDLERS com.sun.facelets.FaceletViewHandler ... I removed it and tried again. This time I received a NoClassDefFoundError: java.lang.NoClassDefFoundError: com/sun/facelets/tag/TagHandler at java.lang.ClassLoader.defineClass1(Native Method) at java.lang.ClassLoader.defineClassCond(ClassLoader.java:632) at java.lang.ClassLoader.defineClass(ClassLoader.java:616) at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:141) at java.net.URLClassLoader.defineClass(URLClassLoader.java:283) at java.net.URLClassLoader.access$000(URLClassLoader.java:58) at java.net.URLClassLoader$1.run(URLClassLoader.java:197) at java.security.AccessController.doPrivileged(Native Method) at java.net.URLClassLoader.findClass(URLClassLoader.java:190) at org.mortbay.jetty.webapp.WebAppClassLoader.loadClass(WebAppClassLoader.java:392) at org.mortbay.jetty.webapp.WebAppClassLoader.loadClass(WebAppClassLoader.java:363) at java.lang.Class.forName0(Native Method) at java.lang.Class.forName(Class.java:247) at org.apache.myfaces.shared_impl.util.ClassUtils.classForName(ClassUtils.java:184) at org.apache.myfaces.view.facelets.util.ReflectionUtil.forName(ReflectionUtil.java:67) Since everything seemed to work with Facelets in the classpath, I decided to save this headache for a later date. I entered two issues in AppFuse's JIRA, one for removing Facelets and one for replacing Ajax4JSF with RichFaces. The next issue I encountered was redirecting from AppFuse's password hint page. The navigation-rule for this page is as follows: navigation-rule> /passwordHint.xhtml success /login With JSF 2.0, the rule changes the URL to /login.xhtml when redirecting (where it was left as /login with 1.2) and it was caught by the security setting in my web.xml that prevents users from viewing raw templates. Protect XHTML Templates *.xhtml To solve this issue, I had to make a couple of changes: Comment out the security-constraint in web.xml and move it to Spring Security's security.xml file. Add a rule to urlrewrite.xml that redirects back to login (since login.xhtml doesn't exist and I'm using extensionless URLs). ^/login.xhtml$ %{context-path}/login After getting the Password Hint feature passing in the browser, I tried running the integration tests (powered by Canoo WebTest). The Password Hint test kept failing with the following error: [ERROR] /Users/mraible/dev/appfuse/web/jsf/src/test/resources/web-tests.xml:51: JavaScript error loading page http://localhost:9876/appfuse-jsf-2.1.0-SNAPSHOT/passwordHint?username=admin: syntax error (http:// localhost:9876/appfuse-jsf-2.1.0-SNAPSHOT/javax.faces.resource/oamSubmit.js.jsf?ln=org.apache.myfaces#122) Figuring this was caused by my hack to submit the form when the page was loaded, I turned to Pretty Faces, which allows you to call a method directly from a URL. After adding the Pretty Faces dependencies to my pom.xml, I created a src/main/webapp/WEB-INF/pretty-config.xml file with the following XML: #{userForm.edit} #{passwordHint.execute} This allowed me to remove both editProfile.xhtml and passwordHint.xhtml, both of which simply auto-submitted forms. At this point, I figured I'd be good to go and ran my integration tests again. The first thing I discovered was that ".jsf" was being tacked onto my pretty URL, most likely by the UrlRewriteFilter. Adding the following to my PasswordHint.java class solved this. if (username.endsWith(".jsf")) { username = username.substring(0, username.indexOf(".jsf")); } The next thing was a cryptic error that took me a while to figure out. DEBUG [1152467051@qtp-144702232-0] PasswordHint.execute(38) | Processing Password Hint... 2011-03-05 05:48:52.471:WARN::/passwordHint/admin com.ocpsoft.pretty.PrettyException: Exception occurred while processing <:#{passwordHint.execute}> null at com.ocpsoft.pretty.faces.beans.ActionExecutor.executeActions(ActionExecutor.java:71) at com.ocpsoft.pretty.faces.event.PrettyPhaseListener.processEvent(PrettyPhaseListener.java:214) at com.ocpsoft.pretty.faces.event.PrettyPhaseListener.afterPhase(PrettyPhaseListener.java:108) at org.apache.myfaces.lifecycle.PhaseListenerManager.informPhaseListenersAfter(PhaseListenerManager.java:111) at org.apache.myfaces.lifecycle.LifecycleImpl.executePhase(LifecycleImpl.java:185) at org.apache.myfaces.lifecycle.LifecycleImpl.execute(LifecycleImpl.java:118) at javax.faces.webapp.FacesServlet.service(FacesServlet.java:189) Digging into the bowels of MyFaces, I discovered a class was looking for a viewId with an extension and no view-id was being set. Adding the following to the top of my execute() method solved this. getFacesContext().getViewRoot().setViewId("/passwordHint.xhtml"); After making this change, all AppFuse's integration tests are passing and the upgrade seems complete. The only other issues I encountered were logging-related. The first is an error about Tomahawk that doesn't seem to affect anything. Mar 5, 2011 6:44:01 AM com.sun.facelets.compiler.TagLibraryConfig loadImplicit SEVERE: Error Loading Library: jar:file:/Users/mraible/.m2/repository/org/apache/myfaces/tomahawk/tomahawk20/1.1.10/tomahawk20-1.1.10.jar!/META-INF/tomahawk.taglib.xml java.io.IOException: Error parsing [jar:file:/Users/mraible/.m2/repository/org/apache/myfaces/tomahawk/tomahawk20/1.1.10/tomahawk20-1.1.10.jar!/META-INF/tomahawk.taglib.xml]: at com.sun.facelets.compiler.TagLibraryConfig.create(TagLibraryConfig.java:410) at com.sun.facelets.compiler.TagLibraryConfig.loadImplicit(TagLibraryConfig.java:431) at com.sun.facelets.compiler.Compiler.initialize(Compiler.java:87) at com.sun.facelets.compiler.Compiler.compile(Compiler.java:104) The second is excessive logging from MyFaces. As far as I can tell, this is because MyFaces switched to java.util.logging instead of commons logging. With all the frameworks that AppFuse leverages, I think it has all the logging frameworks in its classpath now. I was hoping to fix this by posting a message to the mailing list, but haven't received a reply yet. [WARNING] [talledLocalContainer] Mar 5, 2011 6:50:25 AM org.apache.myfaces.config.annotation.TomcatAnnotationLifecycleProvider newInstance [WARNING] [talledLocalContainer] INFO: Creating instance of org.appfuse.webapp.action.BasePage [WARNING] [talledLocalContainer] Mar 5, 2011 6:50:25 AM org.apache.myfaces.config.annotation.TomcatAnnotationLifecycleProvider destroyInstance [WARNING] [talledLocalContainer] INFO: Destroy instance of org.appfuse.webapp.action.BasePage After successfully upgrading AppFuse, I turned to AppFuse Light, where things were much easier. Now that AppFuse uses JSF 2, I hope to start leveraging some of its new features. If you're yearning to get started with them today, I invite you to grab the source and start integrating them yourself. From http://raibledesigns.com/rd/entry/upgrading_to_jsf_2

This tutorial will present examples using advanced result mappings, how to handle mappings with association, collections, the n+1 problem, and more.

While we have been evaluating in our blog posts the various features available on popular Cloud Computing platforms today, I thought it might be a good idea to understand when and how all this started and look back at where this began and trace some of the key events in the progress of cloud computing. Amazon like all other Internet companies in the period of the dot com bubble were left with large amounts of underutilized computing infrastructure, reports suggest less than 10% of the server infrastructure of many companies were being used. Amazon may have use cloud computing as a way to provide this unused resources as utility computing service when they launched S3 as the first true cloud computing service in March 2006. 1. Launch of Amazon Web Services in July 2002 The initial version of AWS in 2002 was focused more on making information available from Amazon to partners through a web services model with programmatic and developer support and was very focused on Amazon as a retailer. While this set the stage for the next steps the launch of S3 was the true step towards building a cloud platform. Amazon Press Release 2. S3 Launches in March 2006 Here are some interesting articles on the launch of S3 in 2006. The real breakthrough however was the pricing model for S3 which defined the model of 'pay-per-use' which has now become the defacto standard for cloud pricing. Also the launch of S3 really defined the shift of Amazon from being just a retailer to a strong player in the technology space. Techcrunch Post on S3 on March 14th, 2006 Read Write Web Post on S3 and EC2 on Nov 3rd, 2006 Business Week Article on Jeff Bezos vision on cloud computing on Nov 13th, 2006 3. EC2 Launches in August 2006 EC2 had a much quieter launch in August 2006 but i would think had the bigger impact by making core computing infrastructure available. This completed the loop on enabling a more complete cloud infrastructure being available. In fact at that time analysts had some difficulty in understanding what the big deal is, and thought it looks similar to other hosting services available online only with a different pricing model. Some interesting articles from that time on the launch: Technologyevangelist Blog Virtualization Info 4. Launch of Google App Engine in April 2008 The launch of Google App Engine in 2008 was the entry of the first pure play technology company into the Cloud Computing market. Google a dominant Internet company entering into this market was clearly a major step towards wide spread adoption of cloud computing. As with all their other products they introduced radical pricing models with a free entry level plan and extremely low cost computing and storage services which are currently among the lowest in the market. Techcrunch post on App Engine Launch Google App Engine Launch Post 5. Windows Azure launches Beta in Nov 2009 The entry of Microsoft into Cloud Computing is a clear indication of the growth of the space. Microsoft for long has not accepted the Internet and the web as a significant market and has continued to focus on the desktop market for all these years. I think this is a realization that a clear shift is taking place. The launch of Azure is a key event in the history of cloud computing with the largest software company making a small but significant shift to the web. Launch of Azure Beta Azure General Availability - Feb 2010 You might also like: Cloud Computing, Google App Engine: How big is the market Really ? Comparing Google App Engine with Amazon EC2 Comparing Amazon EC2 and Microsoft Azure Languages Supported by Google App Engine Cloud Computing: What is it really ?

I've always had a keen interest in implementing security in webapps. I implemented container-managed authentication (CMA) in AppFuse in 2002, watched Tomcat improve it's implementation in 2003 and implemented Remember Me with CMA in 2004. In 2005, I switched from CMA to Acegi Security (now Spring Security) and never looked back. I've been very happy with Spring Security over the years, but also hope to learn more about Apache Shiro and implementing OAuth to protect JavaScript APIs in the near future. I was recently re-inspired to learn more about security when working on a new feature at Overstock.com. The feature hasn't been released yet, but basically boils down to allowing users to login without leaving a page. For example, if they want to leave a review on a product, they would click a link, be prompted to login, enter their credentials, then continue to leave their review. The login prompt and subsequent review would likely be implemented using a lightbox. While lightboxes are often seen in webapps these days because they look good, it's also possible Lightbox UIs provide a poor user experience. User experience aside, I think it's interesting to see what's required to implement such a feature. To demonstrate how we did it, I whipped up an example using AppFuse Light, jQuery and Spring Security. The source is available in my ajax-login project on GitHub. To begin, I wanted to accomplish a number of things to replicate the Overstock environment: Force HTTPS for authentication. Allow testing HTTPS without installing a certificate locally. Implement a RESTful LoginService that allows users to login. Implement login with Ajax, with the request coming from an insecure page. Forcing HTTPS with Spring Security The first feature was fairly easy to implement thanks to Spring Security. Its configuration supports a requires-channel attribute that can be used for this. I used this to force HTTPS on the "users" page and it subsequently causes the login to be secure. Testing HTTPS without adding a certificate locally After making the above change in security.xml, I had to modify my jWebUnit test to work with SSL. In reality, I didn't have to modify the test, I just had to modify the configuration that ran the test. In my last post, I wrote about adding my 'untrusted' cert to my JVM keystore. For some reason, this works for HttpClient, but not for jWebUnit/HtmlUnit. The good news is I figured out an easier solution - adding the trustStore and trustStore password as system properties to the maven-failsafe-plugin configuration. maven-failsafe-plugin 2.7.2 **/*WebTest.java ${project.build.directory}/ssl.keystore appfuse The disadvantage to doing things this way is you'll have to pass these in as arguments when running unit tests in your IDE. Implementing a LoginService Next, I set about implementing a LoginService as a Spring MVC Controller that returns JSON thanks to the @ResponseBody annotation and Jackson. package org.appfuse.examples.web; import org.appfuse.model.User; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.beans.factory.annotation.Qualifier; import org.springframework.security.authentication.AuthenticationManager; import org.springframework.security.authentication.BadCredentialsException; import org.springframework.security.authentication.UsernamePasswordAuthenticationToken; import org.springframework.security.core.Authentication; import org.springframework.security.core.context.SecurityContextHolder; import org.springframework.stereotype.Controller; import org.springframework.web.bind.annotation.RequestMapping; import org.springframework.web.bind.annotation.RequestMethod; import org.springframework.web.bind.annotation.RequestParam; import org.springframework.web.bind.annotation.ResponseBody; @Controller @RequestMapping("/api/login.json") public class LoginService { @Autowired @Qualifier("authenticationManager") AuthenticationManager authenticationManager; @RequestMapping(method = RequestMethod.GET) @ResponseBody public LoginStatus getStatus() { Authentication auth = SecurityContextHolder.getContext().getAuthentication(); if (auth != null && !auth.getName().equals("anonymousUser") && auth.isAuthenticated()) { return new LoginStatus(true, auth.getName()); } else { return new LoginStatus(false, null); } } @RequestMapping(method = RequestMethod.POST) @ResponseBody public LoginStatus login(@RequestParam("j_username") String username, @RequestParam("j_password") String password) { UsernamePasswordAuthenticationToken token = new UsernamePasswordAuthenticationToken(username, password); User details = new User(username); token.setDetails(details); try { Authentication auth = authenticationManager.authenticate(token); SecurityContextHolder.getContext().setAuthentication(auth); return new LoginStatus(auth.isAuthenticated(), auth.getName()); } catch (BadCredentialsException e) { return new LoginStatus(false, null); } } public class LoginStatus { private final boolean loggedIn; private final String username; public LoginStatus(boolean loggedIn, String username) { this.loggedIn = loggedIn; this.username = username; } public boolean isLoggedIn() { return loggedIn; } public String getUsername() { return username; } } } To verify this class worked as expected, I wrote a unit test using JUnit and Mockito. I used Mockito because Overstock is transitioning to it from EasyMock and I've found it very simple to use. package org.appfuse.examples.web; import org.junit.After; import org.junit.Before; import org.junit.Test; import org.mockito.Matchers; import org.springframework.security.authentication.AuthenticationManager; import org.springframework.security.authentication.BadCredentialsException; import org.springframework.security.authentication.TestingAuthenticationToken; import org.springframework.security.core.Authentication; import org.springframework.security.core.context.SecurityContext; import org.springframework.security.core.context.SecurityContextHolder; import org.springframework.security.core.context.SecurityContextImpl; import static org.junit.Assert.*; import static org.mockito.Mockito.*; public class LoginServiceTest { LoginService loginService; AuthenticationManager authenticationManager; @Before public void before() { loginService = new LoginService(); authenticationManager = mock(AuthenticationManager.class); loginService.authenticationManager = authenticationManager; } @After public void after() { SecurityContextHolder.clearContext(); } @Test public void testLoginStatusSuccess() { Authentication auth = new TestingAuthenticationToken("foo", "bar"); auth.setAuthenticated(true); SecurityContext context = new SecurityContextImpl(); context.setAuthentication(auth); SecurityContextHolder.setContext(context); LoginService.LoginStatus status = loginService.getStatus(); assertTrue(status.isLoggedIn()); } @Test public void testLoginStatusFailure() { LoginService.LoginStatus status = loginService.getStatus(); assertFalse(status.isLoggedIn()); } @Test public void testGoodLogin() { Authentication auth = new TestingAuthenticationToken("foo", "bar"); auth.setAuthenticated(true); when(authenticationManager.authenticate(Matchers.anyObject())).thenReturn(auth); LoginService.LoginStatus status = loginService.login("foo", "bar"); assertTrue(status.isLoggedIn()); assertEquals("foo", status.getUsername()); } @Test public void testBadLogin() { Authentication auth = new TestingAuthenticationToken("foo", "bar"); auth.setAuthenticated(false); when(authenticationManager.authenticate(Matchers.anyObject())) .thenThrow(new BadCredentialsException("Bad Credentials")); LoginService.LoginStatus status = loginService.login("foo", "bar"); assertFalse(status.isLoggedIn()); assertEquals(null, status.getUsername()); } } Implement login with Ajax The last feature was the hardest to implement and still isn't fully working as I'd hoped. I used jQuery and jQuery UI to implement a dialog that opens the login page on the same page rather than redirecting to the login page. The "#demo" locator refers to a button in the page. Passing in the "ajax=true" parameter disables SiteMesh decoration on the login page, something that's described in my Ajaxified Body article. var dialog = $(''); $(document).ready(function() { $.get('/login?ajax=true', function(data) { dialog.html(data); dialog.dialog({ autoOpen: false, title: 'Authentication Required' }); }); $('#demo').click(function() { dialog.dialog('open'); // prevent the default action, e.g., following a link return false; }); }); Instead of adding a click handler to a specific id, it's probably better to use a CSS class that indicates authentication is required for a link, or -- even better -- use Ajax to see if the link is secured. The login page then has the following JavaScript to add a click handler to the "login" button that submits the request securely to the LoginService. var getHost = function() { var port = (window.location.port == "8080") ? ":8443" : ""; return ((secure) ? 'https://' : 'http://') + window.location.hostname + port; }; var loginFailed = function(data, status) { $(".error").remove(); $('#username-label').before('Login failed, please try again.'); }; $("#login").live('click', function(e) { e.preventDefault(); $.ajax({url: getHost() + "/api/login.json", type: "POST", data: $("#loginForm").serialize(), success: function(data, status) { if (data.loggedIn) { // success dialog.dialog('close'); location.href= getHost() + '/users'; } else { loginFailed(data); } }, error: loginFailed }); }); The biggest secret to making this all work (the HTTP -> HTTPS communication, which is considered cross-domain), is the window.name Transport and the jQuery plugin that implements it. To make this plugin work with Firefox 3.6, I had to implement a Filter that adds Access-Control headers. A question on Stackoverflow helped me figure this out. public class OptionsHeadersFilter implements Filter { public void doFilter(ServletRequest req, ServletResponse res, FilterChain chain) throws IOException, ServletException { HttpServletResponse response = (HttpServletResponse) res; response.setHeader("Access-Control-Allow-Origin", "*"); response.setHeader("Access-Control-Allow-Methods", "GET,POST"); response.setHeader("Access-Control-Max-Age", "360"); response.setHeader("Access-Control-Allow-Headers", "x-requested-with"); chain.doFilter(req, res); } public void init(FilterConfig filterConfig) { } public void destroy() { } } Issues I encountered a number of issues when implementing this in the ajax-login project. If you try to run this with ports (e.g. 8080 and 8443) in your URLs, you'll get a 501 (Not Implemented) response. Removing the ports by fronting with Apache and mod_proxy solves this problem. If you haven't accepted the certificate in your browser, the Ajax request will fail. In the example, I solved this by clicking on the "Users" tab to make a secure request, then going back to the homepage to try and login. The jQuery window.name version 0.9.1 doesn't work with jQuery 1.5.0. The error is "$.httpSuccess function not found." Finally, even though I was able to authenticate successfully, I was unable to make the authentication persist. I tried adding the following to persist the updated SecurityContext to the session, but it doesn't work. I expect the solution is to create a secure JSESSIONID cookie somehow. @Autowired SecurityContextRepository repository; @RequestMapping(method = RequestMethod.POST) @ResponseBody public LoginStatus login(@RequestParam("j_username") String username, @RequestParam("j_password") String password, HttpServletRequest request, HttpServletResponse response) { UsernamePasswordAuthenticationToken token = new UsernamePasswordAuthenticationToken(username, password); ... try { Authentication auth = authenticationManager.authenticate(token); SecurityContextHolder.getContext().setAuthentication(auth); // save the updated context to the session repository.saveContext(SecurityContextHolder.getContext(), request, response); return new LoginStatus(auth.isAuthenticated(), auth.getName()); } catch (BadCredentialsException e) { return new LoginStatus(false, null); } } Conclusion This article has shown you how to force HTTPS for login, how to do integration testing with a self-generated certificate, how to implement a LoginService with Spring MVC and Spring Security, as well as how to use jQuery to talk to a service cross-domain with the window.name Transport. While I don't have everything working as much as I'd like, I hope this helps you implement a similar feature in your applications. One thing to be aware of is with lightbox/dialog logins and HTTP -> HTTPS is that users won't see a secure icon in their address bar. If your app has sensitive data, you might want to force https for your entire app. OWASP's Secure Login Pages has a lot of good tips in this area. Update: I've posted a demo of the ajax-login webapp. Thanks to Contegix for hosting the demo and helping obtain/install an SSL certificate so quickly. Update March 24, 2011: Rob Winch figured out how to make this work and sent me a patch. From his comment: The first issue is that Access-Control-Allow-Credentials header must be set to true. This is so that the browser knows it can send and accept cookies. The second issue is that XMLHttpRequest.withCredentials should be set to true. The last change was that in order to allow credentials to work across domains, the Access-Control-Allow-Origin must be a specific value (i.e. it won't work if you use a wildcard). For more information, you can read about it on mozilla's site. I've updated the demo with these changes. Works great now - thanks Rob! From http://raibledesigns.com/rd/entry/implementing_ajax_authentication_using_jquery

java classes can get big and hairy, making it difficult to find the method you’re looking for when browsing or editing a class. there is no specific order to where methods can be in a class and different developers have different preferences about where to put them. you could use the mouse wheel and scroll ferociously until you eventually find the method or you could even use page down/page up on your keyboard. but these methods can be time-consuming and haphazard, especially when the class has lots of methods or they’re scattered in an arbitrary order. luckily, eclipse has a number of fast and easy ways to help you navigate methods in a class, especially using the keyboard. i’ll discuss some of those keyboard shortcuts and also which ones to use when. quick outline the quick outline is basically a scaled-down popup version of the outline view. the main advantage over the outline view is that it has a search box that allows you to search for a method. here’s how to use the quick outline: press ctrl+o from anywhere within the class. type a search term in the search box and eclipse will just show all methods that match the search term. by default eclipse does an exact match search, but you can use wildcards. once you see the method you’re interested in, press down to select the method (if it’s not selected already). press enter once the method is selected. eclipse will take you directly to the method’s declaration. this is an example of the popup for java’s arraylist . searching for *rem will search for all method names that contain the word rem . here’s an example: notes: sort the view using the the down arrow menu in the top right corner. it makes it easier to find methods by scanning. resize the quick outline popup to see more methods. eclipse remembers the size of the popup for the next time you open it. next member & previous member another way to move between methods is to use two features called go to next member and go to previous member. when you press ctrl+shift+down , eclipse moves the cursor to the next method in the class. pressing ctrl+shift+up moves to the previous method. here’s a video to give you a quick example of how these shortcuts work: this shortcut works best if you’re already positioned in a method or if the class has few fields. that’s because to eclipse a member can either be a method or a field. if you’re at the top of the class, you have to move through all the fields before you actually start moving through the methods themselves, a time-consuming process especially for bigger classes with lots of fields. it helps to generate getters and setters at the bottom of the class because you don’t have to navigate through them to get to the useful methods. open declaration if you’ve got lots of private methods in your class then open declaration might be the best way to navigate between them. when you’re positioned on a method call and press f3 , eclipse takes you directly to the definition of that method. for example, if you’re busy in the method process() and your cursor’s positioned on initprocessing() , pressing f3 will take you directly to the declaration for that method further down the class. public void process() { //do things... initprocessing(); //... } ... private void initprocessing() { //init something... } this feature works very well with alt+left (backward history). see the section below for more details about the backward history. navigating back to a previously viewed method while browsing code, you’ll often want to return to the previous method you were viewing once you’re done viewing the method it calls. to do this, use alt+left (backward history) to move back to the last navigation point. this feature isn’t specific to just methods, but also works for navigating between previously visited editors. but it works great if you’ve just been browsing methods within a class. quick mentions eclipse’s outline view also allows easy navigation but mostly with the mouse. you could navigate to the view using alt+shift+q, o , and you can move to methods by typing their first letter, but i’ve found the quick outline to be more keyboard friendly. also, the outline view doesn’t support wildcard searches. you can also use eclipse’s call hierarchy ( ctrl+alt+h ) especially if you’re trying to understand the flow of methods in a class and move between them easily. knowing how to navigate between views and editors with the keyboard helps a lot since you’ll be moving between the call hierarchy view and editors a lot. what should i use when? use next/previous member shortcut if the class is small or you have a good idea of where other methods are in relation to the current method (eg. are they above/below the current method). use the quick outline if you don’t know the class too well or there are lots of methods in the class. use open declaration if you’re moving between many private methods of the class. it’s normally the fastest way to move to another private method in the class, but only if you’re already positioned in a method that calls it. from http://eclipseone.wordpress.com/2011/02/21/the-easiest-ways-to-navigate-methods-in-a-class-using-eclipse-keyboard-shortcuts/

This tutorial will walk you through how to setup iBatis (MyBatis) in a simple Java project and will present examples using simple insert, update, select and delete statements using annotations. This is the third tutorial of the iBatis/MyBatis series, you can read the first 2 tutorials on the following links: Introduction to iBatis (MyBatis), An alternative to Hibernate and JDBC Getting Started with iBatis (MyBatis): XML Configuration iBatis/ MyBatis 3 offers a new feature: annotations. But it lacks examples and documentation about annotations. I started to explore and read the MyBatis mailing list archive to write this tutorial. Another thing you will notice is the limitation related to annotations. I am going to demonstrate some examples that you can do with annotations in this tutorial. All the power of iBatis is in its XMl configuration. So let’s play a little bit with annotations. It is much simpler and you can use it for simple queries in small projects. As I already mentioned, if you want something more complex, you will have to use XML configuration. One more thing before we get started: this tutorial is the same as the previous one, but instead of XML, we are going to use annotations. Pre-Requisites For this tutorial I am using: IDE: Eclipse (you can use your favorite one) DataBase: MySQL Libs/jars: Mybatis, MySQL conector and JUnit (for testing) This is how your project should look like: Sample Database Please run this script into your database before getting started with the project implementation: I will not post the sample database here again. You can get it from the previous post about iBatis or download this sample project. The files are the same. 1 – Contact POJO We will create a POJO class first to respresent a contact with id, name, phone number and email address – same as previous post. 2 – ContactMapper In this file, we are going to set up all the queries using annotations. It is the MyBatis-Interface for the SQLSessionFactory. A mapper class is simply an interface with method definitions that match up against the SqlSession methods. Mapper interfaces do not need to implement any interface or extend any class. As long as the method signature can be used to uniquely identify a corresponding mapped statement. Mapper interfaces can extend other interfaces. Be sure that you have the statements in the appropriate namespace when using XML binding to Mapper interfaces. Also, the only limitation is that you cannot have the same method signature in two interfaces in a hierarchy (a bad idea anyway). A mapperclass is simply an interface with method definitions that match up against the SqlSession methods. You can create some strings with the SQL code. Remember it has to be the same code as in XML Configuration. package com.loiane.data; import java.util.List; import org.apache.ibatis.annotations.Delete;import org.apache.ibatis.annotations.Insert;import org.apache.ibatis.annotations.Options;import org.apache.ibatis.annotations.Param;import org.apache.ibatis.annotations.Result;import org.apache.ibatis.annotations.Results;import org.apache.ibatis.annotations.Select;import org.apache.ibatis.annotations.Update; import com.loiane.model.Contact; public interface ContactMapper { final String SELECT_ALL = "SELECT * FROM CONTACT"; final String SELECT_BY_ID = "SELECT * FROM CONTACT WHERE CONTACT_ID = #{id}"; final String UPDATE = "UPDATE CONTACT SET CONTACT_EMAIL = #{email}, CONTACT_NAME = #{name}, CONTACT_PHONE = #{phone} WHERE CONTACT_ID = #{id}"; final String UPDATE_NAME = "UPDATE CONTACT SET CONTACT_NAME = #{name} WHERE CONTACT_ID = #{id}"; final String DELETE = "DELETE FROM CONTACT WHERE CONTACT_ID = #{id}"; final String INSERT = "INSERT INTO CONTACT (CONTACT_EMAIL, CONTACT_NAME, CONTACT_PHONE) VALUES (#{name}, #{phone}, #{email})"; /** * Returns the list of all Contact instances from the database. * @return the list of all Contact instances from the database. */ @Select(SELECT_ALL) @Results(value = { @Result(property="id", column="CONTACT_ID"), @Result(property="name", column="CONTACT_NAME"), @Result(property="phone", column="CONTACT_PHONE"), @Result(property="email", column="CONTACT_EMAIL") }) List selectAll(); /** * Returns a Contact instance from the database. * @param id primary key value used for lookup. * @return A Contact instance with a primary key value equals to pk. null if there is no matching row. */ @Select(SELECT_BY_ID) @Results(value = { @Result(property="id"), @Result(property="name", column="CONTACT_NAME"), @Result(property="phone", column="CONTACT_PHONE"), @Result(property="email", column="CONTACT_EMAIL") }) Contact selectById(int id); /** * Updates an instance of Contact in the database. * @param contact the instance to be updated. */ @Update(UPDATE) void update(Contact contact); /** * Updates an instance of Contact in the database. * @param name name value to be updated. * @param id primary key value used for lookup. */ void updateName(@Param("name") String name, @Param("id") int id); /** * Delete an instance of Contact from the database. * @param id primary key value of the instance to be deleted. */ @Delete(DELETE) void delete(int id); /** * Insert an instance of Contact into the database. * @param contact the instance to be persisted. */ @Insert(INSERT) @Options(useGeneratedKeys = true, keyProperty = "id") void insert(Contact contact);} @Select The @Select annotation is very simple. Let’s take a look at the first select statment of this class: selectAll. Note that you don’t need to use the mapping if your database table columns mach the name of the class atributes. I used different names to use the @Result annotation. If table columns match with atribute names, you don’t need to use the @Result annotation. Not let’s take a look on the second method: selectById. Notice that we have a parameter. It is a simple parameter – easy to use when you have a single parameter. @Update Let’s say you want to update all the columns. You can pass the object as parameter and iBatis will do all the magic for you. Remember to mach the parameter name with the atribute name, otherwise iBatis can get confused, Now let’s say you want to use 2 or 3 paramaters, and they don’t belong to an object. If you take a look at iBatis XML configuration you will see you have to set the option parameterType (remember?) and specify you parameter type in it, in another words, you can use only one parameter. If you are using annotation, you can use more than one parameter using the @Param annotation. @Delete The @Delete annotation is also very simple. It follows the previous rules related to parameters. @Insert The @Insert annotation also follows the rules related to parameters. You can use an object or use the @Param annotation to specify more than one parameter. What about the generation key? Well, if your database supports auto generation key, you can set it up using annotations with the @Options annotation. You will need to specify the option useGeneratedKeys and keyProperty. If your database does not support auto generation key, sorry, but I still did not figure out how to do it (in last case, use can do it manually and then pass as parameter to your insert query). 3 – MyBatisConnectionFactory Every MyBatis application centers around an instance of SqlSessionFactory. A SqlSessionFactory instance can be acquired by using the SqlSessionFactoryBuilder. SqlSessionFactoryBuilder can build a SqlSessionFactory instance from an XML configuration file, of from a custom prepared instance of the Configuration class. An observation about this file: on the previous example, we set the mappers on the iBatis Configuration XML file. Using annotations, we will set the mapper manually. In a future example, I’ll show you how to work with XML and Annotations together. package com.loiane.dao; import java.io.FileNotFoundException;import java.io.IOException;import java.io.Reader; import org.apache.ibatis.io.Resources;import org.apache.ibatis.session.SqlSessionFactory;import org.apache.ibatis.session.SqlSessionFactoryBuilder; import com.loiane.data.ContactMapper; public class MyBatisConnectionFactory { private static SqlSessionFactory sqlSessionFactory; static { try { String resource = "SqlMapConfig.xml"; Reader reader = Resources.getResourceAsReader(resource); if (sqlSessionFactory == null) { sqlSessionFactory = new SqlSessionFactoryBuilder().build(reader); sqlSessionFactory.getConfiguration().addMapper(ContactMapper.class); } } catch (FileNotFoundException fileNotFoundException) { fileNotFoundException.printStackTrace(); } catch (IOException iOException) { iOException.printStackTrace(); } } public static SqlSessionFactory getSqlSessionFactory() { return sqlSessionFactory; } } 4 – ContactDAO Now that we set up everything needed, let’s create our DAO. To call the sql statments, we need to do one more configuration, that is to set and get the mapper from the SqlSessionFactory. Then we just need to call the mapper method. It is a little bit different, but it does the same thing. package com.loiane.dao; import java.util.List; import org.apache.ibatis.session.SqlSession;import org.apache.ibatis.session.SqlSessionFactory; import com.loiane.data.ContactMapper;import com.loiane.model.Contact; public class ContactDAO { private SqlSessionFactory sqlSessionFactory; public ContactDAO(){ sqlSessionFactory = MyBatisConnectionFactory.getSqlSessionFactory(); } /** * Returns the list of all Contact instances from the database. * @return the list of all Contact instances from the database. */ public List selectAll(){ SqlSession session = sqlSessionFactory.openSession(); try { ContactMapper mapper = session.getMapper(ContactMapper.class); List list = mapper.selectAll(); return list; } finally { session.close(); } } /** * Returns a Contact instance from the database. * @param id primary key value used for lookup. * @return A Contact instance with a primary key value equals to pk. null if there is no matching row. */ public Contact selectById(int id){ SqlSession session = sqlSessionFactory.openSession(); try { ContactMapper mapper = session.getMapper(ContactMapper.class); Contact list = mapper.selectById(id); return list; } finally { session.close(); } } /** * Updates an instance of Contact in the database. * @param contact the instance to be updated. */ public void update(Contact contact){ SqlSession session = sqlSessionFactory.openSession(); try { ContactMapper mapper = session.getMapper(ContactMapper.class); mapper.update(contact); session.commit(); } finally { session.close(); } } /** * Updates an instance of Contact in the database. * @param name name value to be updated. * @param id primary key value used for lookup. */ public void updateName(String name, int id){ SqlSession session = sqlSessionFactory.openSession(); try { ContactMapper mapper = session.getMapper(ContactMapper.class); mapper.updateName(name, id); session.commit(); } finally { session.close(); } } /** * Insert an instance of Contact into the database. * @param contact the instance to be persisted. */ public void insert(Contact contact){ SqlSession session = sqlSessionFactory.openSession(); try { ContactMapper mapper = session.getMapper(ContactMapper.class); mapper.insert(contact); session.commit(); } finally { session.close(); } } /** * Delete an instance of Contact from the database. * @param id primary key value of the instance to be deleted. */ public void delete(int id){ SqlSession session = sqlSessionFactory.openSession(); try { ContactMapper mapper = session.getMapper(ContactMapper.class); mapper.delete(id); session.commit(); } finally { session.close(); } } 5 – Mapper Configuration File The MyBatis XML configuration file contains settings and properties that have a dramatic effect on how MyBatis behaves. This time, we do not need to configure alias or xml config files. We did all the magic with annotations, so we have a simple config file with only the information about the database we want to connect with. Download I suggest you to take a look at the org.apache.ibatis.annotations package and try to find out what each annotation can do. Unfortunatelly, you won’t find much documentation or examples on MyBatis website. I also created a TestCase class. If you want to download the complete sample project, you can get it from my GitHub account: https://github.com/loiane/ibatis-annotations-helloworld If you want to download the zip file of the project, just click on download: There are more articles about iBatis to come. Stay tooned! In next articles, I’m going to demonstrate how to implement the feature using XML and then Annotations (when it is possible). Happy Coding! From http://loianegroner.com/2011/02/getting-started-with-ibatis-mybatis-annotations/

This tutorial will walk you through how to setup iBatis (MyBatis) in a simple Java project and will present examples using simple insert, update, select and delete statements.

i started to write a new article series about ibatis / mybatis . this is the first article and it will walk you through what is ibatis / mybatis and why you should use it. for those who does not know ibatis / mybatis yet, it is a persistence framework – an alternative to jdbc and hibernate , available for java and .net platforms. i’ve been working with it for almost two years, and i am enjoying it! the first thing you may notice in this and following articles about ibatis/mybatis is that i am using both ibatis and mybatis terms. why? until june 2010, ibatis was under apache license and since then, the framework founders decided to move it to google code and they renamed it to mybatis. the framework is still the same though, it just has a different name now. i gathered some resources, so i am just going to quote them: what is mybatis/ibatis? the mybatis data mapper framework makes it easier to use a relational database with object-oriented applications. mybatis couples objects with stored procedures or sql statements using a xml descriptor. simplicity is the biggest advantage of the mybatis data mapper over object relational mapping tools.to use the mybatis data mapper, you rely on your own objects, xml, and sql. there is little to learn that you don’t already know. with the mybatis data mapper, you have the full power of both sql and stored procedures at your fingertips. ( www.mybatis.org ) ibatis is based on the idea that there is value in relational databases and sql, and that it is a good idea to embrace the industrywide investment in sql. we have experiences whereby the database and even the sql itself have outlived the application source code, and even multiple versions of the source code. in some cases we have seen that an application was rewritten in a different language, but the sql and database remained largely unchanged. it is for such reasons that ibatis does not attempt to hide sql or avoid sql. it is a persistence layer framework that instead embraces sql by making it easier to work with and easier to integrate into modern object-oriented software. these days, there are rumors that databases and sql threaten our object models, but that does not have to be the case. ibatis can help to ensure that it is not. ( ibatis in action book) so… what is ibatis ? a jdbc framework developers write sql, ibatis executes it using jdbc. no more try/catch/finally/try/catch. an sql mapper automatically maps object properties to prepared statement parameters. automatically maps result sets to objects. support for getting rid of n+1 queries. a transaction manager ibatis will provide transaction management for database operations if no other transaction manager is available. ibatis will use external transaction management (spring, ejb cmt, etc.) if available. great integration with spring, but can also be used without spring (the spring folks were early supporters of ibatis). what isn’t ibatis ? an orm does not generate sql does not have a proprietary query language does not know about object identity does not transparently persist objects does not build an object cache essentially, ibatis is a very lightweight persistence solution that gives you most of the semantics of an o/r mapping toolkit, without all the drama. in other words ,ibatis strives to ease the development of data-driven applications by abstracting the low-level details involved in database communication (loading a database driver, obtaining and managing connections, managing transaction semantics, etc.), as well as providing higher-level orm capabilities (automated and configurable mapping of objects to sql calls, data type conversion management, support for static queries as well as dynamic queries based upon an object’s state, mapping of complex joins to complex object graphs, etc.). ibatis simply maps javabeans to sql statements using a very simple xml descriptor. simplicity is the key advantage of ibatis over other frameworks and object relational mapping tools.( http://www.developersbook.com ) who is using ibatis/mybatis? see the list in this link: http://www.apachebookstore.com/confluence/oss/pages/viewpage.action?pageid=25 i think the biggest case is myspace , with millions of users. very nice! this was just an introduction, so in next articles i will show how to create an application using ibatis/mybatis – step-by-step. enjoy! from http://loianegroner.com/2011/02/introduction-to-ibatis-mybatis-an-alternative-to-hibernate-and-jdbc/

Here’s a quick guide to creating a RESTful web service with Glassfish using JAX-RS. First create a new maven project called restwebdemo using the jee6-sandbox-archetype so we have a model and some data to work with. To get this working with Glassfish, open the persistence.xml file and change the jta-data-source name to jdbc/__default. Also, make sure that the javaDB is up and running by going to $glassfish_dir/bin and typing asadmin start-database. Verify that the application is working correctly by going to http://localhost:8080/restwebdemo/ and you should get a list of courses. Before we start getting to the interesting stuff, we have one more boring piece of configuration to perform specific to web services. We need to add the jersey servlet container to our web.xml file: Jersey Web Application com.sun.jersey.spi.container.servlet.ServletContainer 1 Jersey Web Application /rest/* This also tells Jersey to handle urls starting with /rest and pass it along to our web service methods. Now we can dive right in an create a new server bean that will respond to requests for web services. For now we’ll just return a simple message from a POJO. @Path("sample") public class SimpleService { @Path("greet") @GET public String doGreet() { return "Hello Stranger, the time is "+ new Date(); } } The path annotation on the class indicates that this is a root resource class and the path value given specifies the base URI for all the web service methods contained in the class. On the doGreet method we have @Path which is used to specify the path template this method should match. The @GET annotation is used to differentiate between a sub-resource method that handles the actual web service request and a sub-resource locator method that returns an object that will instead be used to handle the request. In this case, the method has the @GET annotation which means this method handles the request and returns the result. If you navigate to http://localhost:8080/restwebdemo/rest/sample/greet/ you should see a welcome message with the current date and time. Now we’ll look at adding parameterized web services that extracts parameters from the request URL and uses them to form the output. Add the following method to the web service class: @Path("sayHello/{name}") @GET public String doSayHello(@PathParam("name") String name) { return "Hello there "+name; } Again we have the path annotation to indicate what URLs this method will match, and this time we have have {name} added to the URL. This lets us extract a part of the url and give it a name. This name is used in the @PathParam annotation in the method signature to assign the URL fragment to the name parameter . To test our new method, redeploy the application and go to the URL http://localhost:8080/restwebdemo/rest/sample/sayHello/Andy to get the response Hello there Andy We can also use request parameters to provide values to the method by using the @QueryParam annotation. We’ll create another method that is similar but uses a query parameter instead. @Path("sayHello") @GET public String doSayHelloWithRequestParam(@QueryParam("name") String name) { return "Hi there "+name; } This time, the URL to use is http://localhost:8080/restwebdemo/rest/sample/sayHello?name=Andy to get the same message. To make things more interesting, lets add a new page that lets us enter a name in a form and submit it to the web service. Add a new page called form.html with the following content : Name Go to this page at http://localhost:8080/restwebdemo/form.html, enter your name and click submit and you should be greeted by name in the next page. Notice that we had to set the form method to GET because our web service is only set up to respond to GET requests. If we change the form method to POST we can get the following error message : HTTP Status 405 - Method Not Allowed type Status report message Method Not Allowed description The specified HTTP method is not allowed for the requested resource (Method Not Allowed). Remember, with REST, those actual verbs have meaning and adds meaning to the request so it is strict on how it matches the method to be called. To solve this problem, we can add a new method to handle form POSTs like so : @Path("sayHello") @POST public String doSayHelloWithFormParam(@FormParam("name") String name) { return "Hi there " + name; } Here we changed the @GET to a @POST to allow the different verb and changed the annotation on the name method parameter to @FormParam. The path remains the same because we can have service methods that match the same path, but for different request verbs. We can even have the same verb and path as long as the content type returned is different. The content type is used to specify the type of output the is returned from the method. It is set by adding a @javax.ws.rs.Produces (not to be confused with the CDI Produces annotation). The annotation takes a string parameter that indicates the type of media returned from the method. Common media types are defined as constants in the MediaType class so you can use : @Path("sayHello") @POST @Produces(MediaType.APPLICATION_XML) public String doSayHelloWithFormParam(@FormParam("name") String name) { return "Hi there " + name+""; } If you run your form again, and post it, you will get an xml response as follows : Hi there Andy Depending on your browser, if you return just the text, you will get an error because the plain text isn’t valid XML and the browser expects XML because that is the response type set on the response from the web service. To finish up, we are going to do something a little more interesting, we will create a web service to return the name of a course from the database using the sandbox data built into the archetype. For various reasons, we will take the most direct route to getting data access which is to make the web service bean a stateless bean and inject a persistence context using the @PersistenceContext annotation. Add the @Stateless annotation to the SimpleService class and an entity manager field annotated with @PersistenceContext along with the getters and setters. Add a new method to return the course name for the given course id parameter. We will return it as text for the time being : @Path("courseName/{id}") @GET public String getCourseNameFromId(@PathParam("id") Long id) { Course c = entityManager.find(Course.class, id); if (c == null) { return "Not Found, try the index page and come back"; } else { return c.getTitle(); } } Note that the automatic type conversion takes place and the value is converted to a Long automatically. If the course is not found, we suggest the user goes to the main page of the demo. We aren’t just being overly helpful, the test data is generated when you request one of the application pages for the first time. In the current persistence context, when you redeploy, the database is dropped and rebuilt so it will be empty. You need to go to the front page to automatically create the data and then go back to your page to view the course. An example URL is http://localhost:8080/restwebdemo/rest/sample/courseName/124. Of course you could grab the course object and build your own XML or JSON response to send back to the client, or use a third party library like Jackson to build the JSON response. However, as we’ll see next time, Java EE 6 has all these goodies built in for us, and with a few annotations, we’ll be slinging objects back and forth in no time at all. You can download the source code for the project from here. Simply unzip, build with maven (mvn clean package) and deploy to Glassfish.

The Spring Data project provides a solution for accessing data stored in new emerging technologies like NoSQL databases and cloud based services. When we look into the SpringSource git repository we see a lot of spring-data sub-projects: spring-data-commons: common interfaces and utility class for other spring-data projects. spring-data-column: support for column based databases. It has not started yet, but there will be support for Cassandra and HBase spring-data-document: support for document databases. Currently MongoDB and CouchDB are supported. spring-data-graph: support for graph based databases. Currently Neo4j is supported. spring-data-keyvalue: support for key-value databases. Currently Redis and Riak are supported and probably Membase will be supported in future. spring-data-jdbc-ext: JDBC extensions, as example Oracle RAC connection failover is implemented. spring-data-jpa: simplifies JPA based data access layer. I would like to share with you how you can use Redis. The first step is to download it from the redis.io web page. try.redis-db.com is a useful site where we can run Redis commands. It also provides a step by step tutorial. This tutorial shows us all structures that Redis supports (list, set, sorted set and hashes) and some useful commands. A lot of reputable sites use Redis today. After download and unpacking we should compile Redis (version 2.2, the release candidate is the preferable one to use since some commands do not work in version 2.0.4). make sudo make install Once we run these commands we are all set to run the following five commands: redis-benchmark - for benchmarking Redis server redis-check-aof - check the AOF (Aggregate Objective Function), and it can repair that. redis-check-dump - check rdb files for unprocessable opcodes. redis-cli - Redis client. redis-server - Redis server. We can test Redis server. redis-server [1055] 06 Jan 18:19:15 # Warning: no config file specified, using the default config. In order to specify a config file use 'redis-server /path/to/redis.conf' [1055] 06 Jan 18:19:15 * Server started, Redis version 2.0.4 [1055] 06 Jan 18:19:15 * The server is now ready to accept connections on port 6379 [1055] 06 Jan 18:19:15 - 0 clients connected (0 slaves), 1074272 bytes in use and Redis client. redis-cli redis> set my-super-key "my-super-value" OK Now we create a simple Java project in order to show how simple a spring-data-redis module really is. mvn archetype:create -DgroupId=info.pietrowski -DpackageName=info.pietrowski.redis -DartifactId=spring-data-redis -Dpackage=jar Next we have to add in pom.xml milestone spring repository, and add spring-data-redis as a dependency. After that all required dependencies will be fetched. Next we create a resources folder under the main folder, and create application.xml which will have all the configuration. We can configure the JedisConnectionFactory, in two different ways, One - we can provide a JedisShardInfo object in shardInfo property. Two - we can provide host (default localhost), port (default 6379), password (default empty) and timeout (default 2000) properties. One thing to keep in mind is that the JedisShardInfo object has precedence and allows to setup weight, but only allows constructor injection. We can setup the factory to use connection pooling by setting the value of the pooling property to 'true' (default). See application.xml comments to see three different way of configuration. Note: There are two different libraries supported: Jedis and JRedis. They have very similar names and both have the same factory name. See the difference: org.springframework.data.keyvalue.redis.connection.jedis.JedisConnectionFactory org.springframework.data.keyvalue.redis.connection.jredis.JredisConnectionFactory Similar to what we do in Spring, we configure the template object by providing it with a connection factory. We will perform all the operations through this template object. By default we need to provide only Connection Factory, but there are more properties we can provide: exposeConnection (default false) - if we return real connection or proxy object. keySerializer, hashKeySerializer, valueSerializer, hashValueSerializer (default JdkSerializationRedisSerializer) which delegates serialization to Java serialization mechanism. stringSerializer (default StringRedisSerializer) which is simple String to byte[] (and back) serializer with UTF8 encoding. We are ready to execute some code which will be cooperating with the Redis instance. Spring-Data provides us with two ways of interaction, First is by using the execute method and providing a RedisCallback object. Second is by using *Operations helpers (these will be explained later) When we are using RedisCallback we have access to low level Redis commands, see this list of interfaces (I won't put all the methods here because it is huge list): RedisConnection - gathers all Redis commands plus connection management. RedisCommands - gathers all Redis commands (listed beloved). RedisHashCommands - Hash-specific Redis commands. RedisListCommands - List-specific Redis commands. RedisSetCommands - Set-specific Redis commands. RedisStringCommands - key/value specific Redis commands. RedisTxCommands - Transaction/Batch specific Redis commands. RedisZSetCommands - Sorted Set-specific Redis commands. Check RedisCallbackExample class, this was the hard way and the problem is we have to convert our objects into byte arrays in both directions, the second way is easier. Spring Data provides for us with Operations objects, so we have much more simpler API and all byte<->object conversion is made by serializer we setup (or the default one). Higher level API (you will easily recognize *Operation *Commands equivalents): HashOperations - Redis hash operations. ListOperations - Redis list operations. SetOperations - Redis set operations. ValueOperations - Redis 'string' operations. ZSetOperations - Redis sorted set operations. Most of methods get key as first parameters so we have an even better API for multiple operations on the same key: BoundHashOperations - Redis hash operations for specific key. BoundListOperations - Redis list operations for specific key. BoundSetOperations - Redis set operations for specific key. BoundValueOperations - Redis 'string' operations for specific key. BoundZSetOperations - Redis sorted set operations for specific key. Check RedisCallbackExample class to see some easy examples of *Operations usage. One important thing to mention is that you should use stringSerializers for keys, otherwise you will have problems from other clients, because standard serialization adds class information. Otherwise you end up keys such as: "\xac\xed\x00\x05t\x00\x05atInt" "\xac\xed\x00\x05t\x00\nmySuperKey" "\xac\xed\x00\x05t\x00\bsuperKey" Up until now we have just checked the API for Redis, but Spring Data offers more for us. All the cool stuff is in org.springframework.data.keyvalue.redis.support package and all sub-packages. We have: RedisAtomicInteger - Atomic integer (CAS operation) backed by Redis. RedisAtomicLong - Same as previous for Long. RedisList - Redis extension for List, Queue, Deque, BlockingDeque and BlockingQueue with two additional methods List range(start, end) and RedisList trim(start, end). RedisSet - Redis extension for Set with additional methods: diff, diffAndStore, intersect, intersectAndStore, union, unionAndStore. RedisZSet - Redis extension for SortedSet. Note that Comparator is not applicable here so this interface extends normal Set and provide proper methods similar to SortedSet. RedisMap - Redis extension for Map with additional Long increment(key, delta) method Every interface currently has one Default implementation. Check application-support.xml for examples of configuration and RedisSupportClassesExample for examples of use. There is lot of useful information in the comments as well. Summary The library is a first milestone release so there are minor bugs, the documentation isn't as perfect as we used to and the current version needs no stable Redis server. But this is definitely a great library which allows us to use all this cool NoSQL stuff in a "standard" Spring Data Access manner. Awesome job! This post is only useful if you checkout the code: from bitbucket , for the lazy ones here is spring-data-redis zip file as well. This post is originally from http://pietrowski.info/2011/01/spring-data-redis-tutorial/

Generally NetBeans IDE works with a default workspace. In this scenario, if you want to manage multiple sets of projects, you have to create a project group, which allows you to switch between project groups as and when required. But the problem in this is that if the workspace is damaged, and you delete it, all your settings are lost and everything is reset to the default NetBeans IDE settings. The solution is to work with multiple workspaces, that is, multiple instances, of NetBeans IDE. And here is how to do that: Right-click the NetBeans IDE shortcut and choose "Properties". In the shortcut tab, in Target, type after netbeans.exe "--userdir [Folder Path]". Make another shortcut of NetBeans IDE and provide a different folder path. Like this you can create as many workspaces as you want. If one workspace is damaged, it will not effect the settings of the others. Isn't that great? :) Also posted at: http://goo.gl/fb/rrvnA

I've blogged a few times now about Git (which I pronounce with a hard 'g' a la "get", as it's supposed to be named for Linus Torvalds, a self-described git, but which I've also heard called pronounced with a soft 'g' like "jet"). Either way, I'm finding it way more efficient and less painful than either CVS or SVN combined. So, to continue this series ([1], [2], [3]), here is how (and why) to pull an SVN repo down as a Git repo, but with the omission of old (irrelevant) revisions and branches. Using SVN for SVN repos In days of yore when working with the JBoss Tools and JBoss Developer Studio SVN repos, I would keep a copy of everything in trunk on disk, plus the current active branch (most recent milestone or stable branch maintenance). With all the SVN metadata, this would eat up substantial amounts of disk space but still require network access to pull any old history of files. The two repos were about 2G of space on disk, for each branch. Sure, there's tooling to be able to diff and merge between branches w/o having both branches physically checked out, but nothing beats the ability to place two folders side by side OFFLINE for deep comparisons. So, at times, I would burn as much as 6-8G of disk simply to have a few branches of source for comparison and merging. With my painfullly slow IDE drive, this would grind my machine to a halt, especially when doing any SVN operation or counting files / disk usage. Using Git for SVN repos naively Recently, I started using git-svn to pull the whole JBDS repo into a local Git repo, but it was slow to create and still unwieldy. And the JBoss Tools repo was too large to even create as a Git repo - the operation would run out of memory while processing old revisions of code to play forward. At this point, I was stuck having individual Git repos for each JBoss Tools component (major source folder) in SVN: archives, as, birt, bpel, build, etc. It worked, but replicating it when I needed to create a matching repo-collection for a branch was painful and time-consuming. As well, all the old revision information was eating even more disk than before: jbosstools' trunk as multiple git-svn clones: 6.1G devstudio's trunk as single git-svn clone: 1.3G So, now, instead of a couple Gb per branch, I was at nearly 4x as much disk usage. But at least I could work offline and not deal w/ network-intense activity just to check history or commit a change. Still, far from ideal. Cloning SVN with standard layout & partial history This past week, I discovered two ways to make the git-svn experience at least an order of magnitude better: Standard layout (-s) - this allows your generated Git repo to contain the usual trunk, branches/* and tags/* layout that's present in the source SVN repo. This is a win because it means your repo will contain the branch information so you can easily switch between branches within the same repo on disk. No more remote network access needed! Revision filter (-r) - this allows your generated Git repo to start from a known revision number instead of starting at its birth. Now instead of taking hours to generate, you can get a repo in minutes by excluding irrelevant (ancient) revisions. So, why is this cool? Because now, instead of having 2G of source+metadata to copy when I want to do a local comparison between branches, the size on disk is merely: jbosstools' trunk as single git-svn clone w/ trunk and single branch: 1.3G devstudio's trunk as single git-svn clone w/ trunk and single branch: 0.13G So, not only is the footprint smaller, but the performance is better and I need never do a full clone (or svn checkout) again - instead, I can just copy the existing Git repo, and rebase it to a different branch. Instead of hours, this operation takes seconds (or minutes) and happens without the need for a network connection. Okay, enough blather. Show me the code! Check out the repo, including only the trunk & most recent branch # Figure out the revision number based on when a branch was created, then # from r28571, returns -r28571:HEAD rev=$(svn log --stop-on-copy \ http://svn.jboss.org/repos/jbosstools/branches/jbosstools-3.2.x \ | egrep "r[0-9]+" | tail -1 | sed -e "s#\(r[0-9]\+\).\+#-\1:HEAD#") # now, fetch repo starting from the branch's initial commit git svn clone -s $rev http://svn.jboss.org/repos/jbosstools jbosstools_GIT Now you have a repo which contains trunk & a single branch git branch -a # list local (Git) and remote (SVN) branches * master remotes/jbosstools-3.2.x remotes/trunk Switch to the branch git checkout -b local/jbosstools-3.2.x jbosstools-3.2.x # connect a new local branch to remote one Checking out files: 100% (609/609), done. Switched to a new branch 'local/jbosstools-3.2.x' git svn info # verify now working in branch URL: http://svn.jboss.org/repos/jbosstools/branches/jbosstools-3.2.x Repository Root: http://svn.jboss.org/repos/jbosstools Switch back to trunk git checkout -b local/trunk trunk # connect a new local branch to remote trunk Switched to a new branch 'local/trunk' git svn info # verify now working in branch URL: http://svn.jboss.org/repos/jbosstools/trunk Repository Root: http://svn.jboss.org/repos/jbosstools Rewind your changes, pull updates from SVN repo, apply your changes; won't work if you have local uncommitted changes git svn rebase Fetch updates from SVN repo (ignoring local changes?) git svn fetch Create a new branch (remotely with SVN) svn copy \ http://svn.jboss.org/repos/jbosstools/branches/jbosstools-3.2.x \ http://svn.jboss.org/repos/jbosstools/branches/some-new-branch From http://divby0.blogspot.com/2011/01/howto-partially-clone-svn-repo-to-git.html

It’s possible to use Apache Ivy with dependencies defined in pom.xml instead of its native ivy.xml but you will need to apply some workarounds and you’re loosing access to some functionality that you might (or might not) need. The problem is that in a POM you can provide only a subset of settings available in ivy.xml and that Ivy understands only a subset of POM’s syntax. The information here is based mostly on Ivy 2.1.0. Disclaimer: I’m no Ivy expert and there are certainly better ways to achieve what I did. Also newer versions of Ivy may be better. Limitations of pom.xml usage Ivy understands only a subset of POM’s syntax: dependencies, dependencies of plugins or st. like that, parent module. To learn exactly what parts of a pom.xml are processed by Ivy check the two main classes responsible for that (version 2.1.0): PomModuleDescriptorParser.java and PomReader.java. Issues & solutions Referring to a parent POM In general you can user a parent POM, for example do declare properties that you then use e.g. in dependecy declarations, but there are few issues with parent POMs: Ivy ignores the relativePath element Ivy ignores the packaging=pom on the parent module Ivy ignores the relativePath element You can specify a parent project in your POM. Maven allows you to provide absolute or relative system path to the pom like this: But Ivy will ignore the relativePath and will only try to find it via a resolver (which might be OK for you but wasn’t for me). com.ibm.education lms-root-pom 1.0-SNAPSHOT ../lms.build/lms-root-pom/pom.xml Workaround Declare a special local file-system resolver for the parent pom Configure modules in ivysettings so that this resolver is used only for the parent pom module The special FS resolver for the parent pom: ... (ivy.settings.dir is automatically set by Ivy based on the file attribute of the ivy:settings task; just make sure to use file= and not url=) Module declaration: ... ... File structure: lms.build lms-root-pom pom.xml emptyJarToSatisfyIvy.jar (see below) your-dependant-module pom.xml Ivy ignores the packaging=pom on the parent module Ivy ignores the packaging=pom on the parent module and will always try to find a .jar for it, thus wasting precious time. The workaround is to create a fake, empty .jar, for example via echo “” > emptyJarToSatisfyIvy.jar. You can see it above in the lms-root-pom file structure and resolver’s configuration. Publishing pom.xml to a Maven repository and respecting the dependencies of your own modules I suppose you want to publish your own modules to a Maven repository manager such as Nexus or Artifactory. And you also want to publish module’s pom.xml with its dependencies and when you have another module depending on this one, you want Ivy to be aware of the (transitive) dependencies from the pom. Publishing the pom.xml Normally Ivy publishes only the single artifact .. If you used ivy.xml you could declare additional artifacts in its / however pom.xml gives you no such possibility. Fortunately, since Ivy 2.2.0, it’s possible to declare the additional artifacts with the element also under the Ant ivy:publish task: It’s essential that the name of the POM artifact is -.pom, otherwise it won’t be recognized as the artifact’s POM when retrieving it. It is achieved by using the Ivy-provided property ivy.module and ext=pom. The attributes of ivy:publish are mostly unimportant, I’ve them like this for this is used for publishing snapshots. Configuring Ivy to fetch the POM and respect the dependencies Ivy will automatically respect dependencies in a POM but it must know that it should look for this file. To do that you must use the ibiblio resolver to retrieve artifacts from the repository. And, of course, there must be an -.pom file next to the main .jar. But it doesn’t support publishing (at least so I believe) and therefore you also need to declare an URL resolver for publishing of your artifacts: ... To check it, look into /.ivy2/cache// – there should be ivy-.xml .original, which is actually a renamed pom.xml and ivy-.xml, generated from that. Especially look there into ivydata-.xml, it contains information about the artifact’s metadata etc. In the ideal case it is similar to: #ivy cached data file for com.ibm.education#lms.ab.common;40.0.0-SNAPSHOT #Wed Jan 26 12:11:17 CET 2011 artifact\:lms.ab.common\#jar\#jar\#-869122099.is-local=false artifact.resolver=shared-snapshot-retrieval artifact\:lms.ab.common\#pom.original\#pom\#783440563.location=http\://e25ciwas020.toronto.ca.ibm.com\:8081/nexus/content/repositories /snapshots/com/ibm/education/lms.ab.common/40.0.0-SNAPSHOT/lms.ab.common-40.0.0-SNAPSHOT.pom artifact\:lms.ab.common\#pom.original\#pom\#783440563.is-local=false artifact\:lms.ab.common\#jar\#jar\#-869122099.location=http\://e25ciwas020.toronto.ca.ibm.com\:8081/nexus/content/repositories /snapshots/com/ibm/education/lms.ab.common/40.0.0-SNAPSHOT/lms.ab.common-40.0.0-SNAPSHOT.jar resolver=shared-snapshot-retrieval artifact\:ivy\#ivy\#xml\#1489462886.is-local=false artifact\:ivy\#ivy\#xml\#1489462886.location=http\://e25ciwas020.toronto.ca.ibm.com\:8081/nexus/content/repositories /snapshots/com/ibm/education/lms.ab.common/40.0.0-SNAPSHOT/lms.ab.common-40.0.0-SNAPSHOT.pom Mapping of configurations (scopes) While Ivy let you define which dependencies should be fetched in which situation including the transitive one so that you can easily declare that a dependency’s “provided” dependencies should be respected during compilation and testing, with pom.xml you lose the ability to declare these configuration mappings and you have to live with the defaults. This means for example that a dependency’s dependencies with the scope=provided are always ignored. The solution is to use only the scope=compile for dependencies in your modules/artifacts that should be reused and manually filter out the dependencies you don’t want to include in your binary (e.g. a .war). Conclusion It’s possible to use Ivy 2.2.0 with Maven POMs but you should carefully explore the limitations of this approach and check them against your requirements. Good luck! From http://theholyjava.wordpress.com/2011/01/26/using-ivy-with-pom-xml/