A preview of our new research guide: The DZone Guide to the Java Ecosystem, from Ivar Grimstad about how to build microservices and use containers in Java.
It's possible to create a desktop appliction using JavaScript, and this tutorial will show you how to do it, using Angular and Bootstrap for the presentation layer.
These two simple steps will allow you to configure versioned resource URLs in Spring MVC, allowing the browser to cache resources for an unlimited time and update version info on the URL when a resource is changed.
Here's a fun little experiment showing the power of Swift's Protocol Extensions to apply a CIGaussianBlur Core Image filter to any UIView with no developer overhead. The code could be extended to apply any Core Image filter such as a half tone screen or colour adjustment. Blurable is a simple protocol that borrows some of the methods and variables from a UIView: var layer: CALayer { get } var subviews: [UIView] { get } var frame: CGRect { get } func addSubview(view: UIView) func bringSubviewToFront(view: UIView) ...and adds a few of its own: Obviously, just being a protocol, it doesn't do much on its own. However, by adding an extension, I can introduce default functionality. Furthermore, by extending UIView to implement Blurable, every component from a segmented control to a horizontal slider can be blurred: extension UIView: Blurable { } The Mechanics of Blurable Getting a blurred representation of a UIView is pretty simple: I need to begin an image context, use the view's layer's renderInContext method to render into the context and then get a UIImage from the context: UIGraphicsBeginImageContextWithOptions(CGSize(width: frame.width, height: frame.height), false, 1) layer.renderInContext(UIGraphicsGetCurrentContext()!) let image = UIGraphicsGetImageFromCurrentImageContext() UIGraphicsEndImageContext(); Once I have the image populated, it's a fairly standard workflow to apply a Gaussian blur to it: guard let blur = CIFilter(name: "CIGaussianBlur") else { return } blur.setValue(CIImage(image: image), forKey: kCIInputImageKey) blur.setValue(blurRadius, forKey: kCIInputRadiusKey) let ciContext = CIContext(options: nil) let result = blur.valueForKey(kCIOutputImageKey) as! CIImage! let boundingRect = CGRect(x: -blurRadius * 4, y: -blurRadius * 4, width: frame.width + (blurRadius * 8), height: frame.height + (blurRadius * 8)) let cgImage = ciContext.createCGImage(result, fromRect: boundingRect) let filteredImage = UIImage(CGImage: cgImage) A blurred image will be larger than its input image, so I need to be explicit about the size I require in createCGImage. The next step is to add a UIImageView to my view and hide all the other views. I've subclassed UIImageView to BlurOverlay so that when it comes to removing it, I can be sure I'm not removing an existing UIImageView: let blurOverlay = BlurOverlay() blurOverlay.frame = boundingRect blurOverlay.image = filteredImage subviews.forEach{ $0.hidden = true } addSubview(blurOverlay) When it comes to de-blurring, I want to ensure the last subview is one of my BlurOverlay remove it and unhide the existing views: func unBlur() { if let blurOverlay = subviews.last as? BlurOverlay { blurOverlay.removeFromSuperview() subviews.forEach{ $0.hidden = false } } } Finally, to see if a UIView is currently blurred, I just need to see if its last subview is a BlurOverlay: var isBlurred: Bool { return subviews.last is BlurOverlay } Blurring a UIView To blur and de-blur, just invoke blur() and unBlur() on an UIView: segmentedControl.unBlur() segmentedControl.blur(blurRadius: 2) Source Code As always, the source code for this project is available at my GitHub repository here. Enjoy!
I am going to explain how to use Spring Security in a Spring MVC Application to authenticate and authorize users against user details stored in a MySQL Database.
Apache Struts 2 and SpringMVC, these two are the most popular and much talked about Java web frameworks today. Many of you might have worked with both of these frameworks, but which is one is better to use? What are the basic differences between both of these frameworks? Well, Apache Struts 2 is an elegant and extensible framework that is used for creating enterprise-level Java web applications. It is designed to streamline the development cycle, starting from building to deployment and maintenance of the application. In Struts, the object that is taking care of a request and routes it for further processing is known as “Action”. On the other hand, Spring MVC is a part of a huge Spring framework stack containing other Spring modules. This means that it doesn’t allow developers to run it without Spring, but the developers can run the Spring Core without Spring MVC. The Spring MVC (Model View Controller) is designed around a DispatcherServlet, which dispatches the requests to handler with configurable handler mappings, view resolution and theme resolution. While the objects responsible for handling requests and routing for processing in Struts called an Action, the same object is referred as Controller in Spring Web MVC framework. This is one of the very first differences between Spring MVC and Struts2. Struts 2 Actions are initiated every time when a request is made, whereas in Spring MVC the Controllers are created only once, stored in memory and shared among all the requests. So, Spring Web MVC framework is far efficient to handle the requests than Struts 2. If we talk about the features, Struts 2 and Spring MVC framework caters different level of business requirements. Let’s take a look at features offered by both of these frameworks. Struts 2 features Configurable MVC components, which are stored in struts.xml file. If you want to change anything, you can easily do it in the xml file. POJO based actions. Struts 2 action class is Plain Old Java Object, which prevents developers to implement any interface or inherit any class. Support for Ajax, which is used to make asynchronous request. It only sends needed field data rather than providing unnecessary information, which at the end improves the performance. Support for integration with Hibernate, Spring, Tiles and so on. Whether you want to use JSP, freemarker, velocity or anything else, you can use different kinds of result types in Struts 2. You can also leverage from various tags like UI tags, Data tags, control tags and more. Brings ample support for theme and template. Struts 2 supports three different kinds of themes including xhtml, simple and css_xhtml. On the other hand, Spring MVC framework brings totally different set of features. Spring MVC features Neat and clear separation of roles. Whether it is controller, command object, form object or anything else, it can be easily fulfilled with the help of a specialized object. Leverage from the adaptability, non-intrusiveness and flexibility with the help of controller method signature. Now use existing business objects as command or form object rather than duplicating them to extend the specific framework base class. Customizable binding and validation will enable manual parsing and conversion to business objects rather than using conventional string. Flexible mode transfer enables easy integration with the latest technology. Customizable locale and theme resolution, support for JSPs with or without Spring tag library for JSTL and so on. Leverage from the simple, but powerful JSP tag library known as Spring tag library. It provides support for various features like data binding and themes. Of course, Struts is one of the most powerful Java application frameworks that can be used in a variety of Java applications. It brings a gamut of services that includes enterprise level services to the POJO. On the other hand, Spring utilizes the dependency injection to achieve the simplification and enhance the testability. Both of these frameworks have their own set of pros and cons associated with it. Struts framework brings a whole host of benefits including: Simplified design Ease of using plug-in Simplified ActionForm & annotations Far better tag features OGNL integration AJAX Support Multiple view options and more However, the only drawback with Struts 2 framework is that it has compatibility issues and poor documentation. On the other hand, Spring MVC provides benefits like: Clear separation between controllers, JavaBeans models and views that is not possible in Struts. Spring MVC is more flexible as compared to the Struts. Spring can be used with different platforms like Velocity, XLST or various other view technologies. There is nothing like ActionForm in Spring, but binds directly to the domain objects. Code is also more testable as compared to the Struts. It is a complete J2EE framework comprising of seven independent layers, which simplifies integration with other frameworks. It doesn’t provide a framework for implementing the business domain and logic, which helps developers create a controller and a view for the application. However, like any other technologies or platforms, Spring MVC too suffers from several criticisms related to the complexity of the Spring framework. Final Verdict Either framework is a great choice. However, if you’re looking for the stable framework, Struts 2 is the right choice for you. On the other hand, if you’re looking for something robust, SpringMVC is perfect. Ensure that you review your exact requirements before choosing the framework!
Multiple return statements in a method will cause your code not to be purely object-oriented. Here you'll find an example where you can use a clean OOP approach instead of using multiple returns.
Spring Framework is the most popular Java framework used for building enterprise class applications. Oracle is the most popular database used in the enterprise. Let's put these two together!
