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"Since 1994, the Java programming language evolved and became a valid tool to develop reliable and performant server applications as opposed to just applets and client applications. The major disadvantage of the Java platform is that still today the only portable way to start a Java application relies on a single point of entry: the public static void main(String[]) method. Having a single-point of entry is a valid solution for client applications, where interactively a user can command to the application to quit (which can terminate the Virtual Machine process at calling the System.exit(int) method), but in those cases where the application is not interactive (server applications) there is currently no portable way to notify the Virtual Machine of its imminent shutdown. A server application written in Java might have to perform several tasks before being able to shutdown the Virtual Machine process. For example in the case of a Servlet container, before the VM process is shut down, sessions might need to be serialized to disk, and web applications need to be destroyed. One common solution to this problem is to create (for example) a ServerSocket and wait for a particular message to be issued. When the message is received, all operations required to shut down the server applications are performed and at the end the System.exit method is called to terminate the Virtual Machine process. This method however, has several disadvantages and risks: In case of a system-wide shutdown, the Virtual Machine process may be shut down directly by the operating system without notifying the running server application. If an attacker finds out the shutdown message to send to the server and discovers a way to send this message, he can easily interrupt the server's operation, bypassing all the security restrictions implemented in the operating system. Most multi-user operating systems already have a way in which server applications are started and stopped. Under Unix based

migrate4j is a database migration tool. Suppose you determine that you need a new database table for your project. If you develop alone, you could write an SQL script that adds a table and manually apply this to your development system. But if you work with other developers, or need to keep a test system in synch with your development system, this become tedious and error prone. Migration tools make it possible to add your new table (or make any other schema changes) in an automated fashion, ensuring all your systems are always in synch. Migration tools also make it possible to quickly and easily roll back previous changes. Unlike typing commands into an interactive SQL window or storing SQL scripts, migration tools keep a detailed history of how your database schema evolved (just in case you need to go back to a previous version). Finally, migration tools minimize or eliminate the problem of having to use vendor specific syntax - you may never switch database products, but if you do, using a migration tool will make your life much easier. The initial intent of migrate4j was to make a Java version of Ruby's db:migrate. If you've used db:migrate, you probably fell in love with it's simple syntax, easy configuration and ability to roll changes up and back effortlessly. The intent (and the challenge) of migrate4j is to bring the power and simplicity of db:migrate to Java programmers, using familiar type safety and syntax. Along the way, we're adding additional functionality that makes migrate4j more than just another Ruby tool rewritten for Java - it is a Java project intended to make other Java projects even better.

"The NetKernel Resource Oriented Computing (ROC) platform separates architecture from code. With ROC you can compose your architectural design independently from implementation code. By keeping the details of code separate from high-level information architecture you gain: freedom of choice in implementation language rapid click-fit compositional development long-term evolvable solutions Threading and scheduling is managed by the microkernel so your code execution is efficiently optimised with linear scaling on multi-core without the need to learn new languages. Something brand-new also comes from separating architecture and code. NetKernel provides system-wide caching of every area of your system. For free. No configuration. NetKernel learns what information is reusable and reuses it. This makes NetKernel systems fast. Very fast."

Aspect-oriented computing is continuing to increase in popularity. The modularity inherent in OSGi and Eclipse offers unique opportunities for managing and applying aspects by supplying them in bundles and directing their application to particular sets of bundles. This incubator work area is dedicated to delivering an integration of aspects and OSGi. The goal is to allow developers to use the Equinox together with AspectJ by combining the benefits of both worlds. Using a load-time weaving extension you are able to add AspectJ aspects to your bundle-based system just by putting them into general OSGi bundles. It does not matter if the pointcuts you defined inside the aspects contain join points that are defined by classes within the same bundle or any other bundle in your installation. The load-time weaving extension will take care that your aspects are woven with the appropriate classes at load-time. To illustrate this lets assume the following situation: You would like to write an aspect that traces something within the JDT plug-ins of Eclipse. Without some kind of load-time aspect weaving you would somehow need to recompile those JDT plug-ins using AJDT (for example) together with your aspect. By using the load-time aspect weaving extension all you need is to implement your aspect and add that bundle to your system. The load-time aspect weaving extension takes care of weaving your aspect with the JDT code as it is loaded. And it doesn't matter if a new JDT is installed by the user later on. The next time your application is started the load-time aspect weaving will take care of weaving your aspect into these bundles as well, if necessary. With this technology is becomes possible to modularize crosscutting concerns across different plug-ins while keeping the idea of separate compilation for bundles. Goals Provide Runtime Modularity and Versioning for Crosscutting Concerns: Aspects are used to implement crosscutting concerns. However such concerns usually compr

Sapphire - develop UI without wiring individual widgets Little has changed in the way Java desktop UI is written since the original Java release. Technologies have changed (AWT, Swing, SWT, etc.), but fundamentals remain the same. The developer must choose which widgets to use, how to lay those widgets out, how to store the data being edited and how to synchronize the model with the UI. Even the best developers fall into traps of having UI components talk directly to other UI components rather than through the model. Inordinate amount of time is spent debugging layout and data-binding issues. Sapphire aims to raise UI writing to a higher level of abstraction. The core premise is that the basic building block of UI should not be a widget (text box, label, button, etc.), but rather a property editor. Unlike a widget, a property editor analyzes metadata associated with a given property, renders the appropriate widgets to edit that property and wires up data binding. Data is synchronized, validation is passed from the model to the UI, content assistance is made available, etc. This fundamentally changes the way developers interact with a UI framework. Instead of writing UI by telling the system how to do something, the developer tells the system what they intend to accomplish. When using Sapphire, the developer says "I want to edit LastName property of the person object". When using widget toolkits like SWT, the developer says "create label, create text box, lay them out like so, configure their settings, setup data binding and so on". By the time the developer is done, it is hard to see the original goal in the code that's produced. This results in UI that is inconsistent, brittle and difficult to maintain.

Unicode system is a international standard encoding.Let's learn why unicode is used in java

" Jump to: navigation, search Welcome to our Wiki. This is the Wiki home page for the Buckminster Component Assembly project, an Eclipse Tools sub project. Buckminster is a component resolution & materialization framework. Its purpose is to get software components for you and materialize them in a context of choice, typically a workspace or file system. This applies whether you are looking at what's available on your local machine, within your development organization or in the public open source cloud. Buckminster reuses existing investments in a wide range of build and source management tools - Maven, ANT, CVS, SVN, PDE, etc. It removes ambiguity from component descriptions, enables component sharing and increases productiveness when applied in development, build, assembly and deploy scenarios. "

"Implementation of Units of Measurement services. A coordinates module compliant with OGC/ISO specifications for the development and deployment of geographic applications. A rigourous mapping of mathematical structures (e.g. Group, Ring, Field, VectorSpace ) to Java interfaces. A linear algebra module, which includes a first (and I believe unique) parameterized matrix class capable of resolving linear system of equations involving any kind of elements (e.g. Complex, ModuloInteger, RationalFunctions) A functions module for symbolic calculations and analysis. Different types of numbers such as real numbers of arbitrary and guaranteed precision, or the always exact rational numbers. Support for exact or arbitrary precision measurements (also strongly typed). Support for Standard , Relativistic , High-Energy , Quantum and Natural physical models. A monetary module for precision-guaranteed calculations and currencies conversions."

"LMAX aims to be the fastest trading platform in the world. Clearly, in order to achieve this we needed to do something special to achieve very low-latency and high-throughput with our Java platform. Performance testing showed that using queues to pass data between stages of the system was introducing latency, so we focused on optimising this area. "

"In todays business environment data corruption can have serious consequences for the enterprise including service unavailability, system reconciliation costs, and damage to customer relationships and business reputation. The JBoss Transaction Service (JBossTS) protects businesses from data corruption by guaranteeing complete, accurate business transactions for Java based applications (including those written for the JEE and EJB frameworks) thereby eliminating the risks and costs associated with time-consuming manual reconciliation following failures."

Android Tutorial. Android is a software package containing linux based operating system for mobile devices such as tablet computers, smartphones etc, middleware and key mobile applicaitons.

XStream is a simple library to serialize objects to XML and back again. Features Ease of use. A high level facade is supplied that simplifies common use cases. No mappings required. Most objects can be serialized without need for specifying mappings. Performance. Speed and low memory footprint are a crucial part of the design, making it suitable for large object graphs or systems with high message throughput. Clean XML. No information is duplicated that can be obtained via reflection. This results in XML that is easier to read for humans and more compact than native Java serialization. Requires no modifications to objects. Serializes internal fields, including private and final. Supports non-public and inner classes. Classes are not required to have default constructor. Full object graph support. Duplicate references encountered in the object-model will be maintained. Supports circular references. Integrates with other XML APIs. By implementing an interface, XStream can serialize directly to/from any tree structure (not just XML). Customizable conversion strategies. Strategies can be registered allowing customization of how particular types are represented as XML. Error messages. When an exception occurs due to malformed XML, detailed diagnostics are provided to help isolate and fix the problem. Alternative output format. The modular design allows other output formats. XStream ships currently with JSON support and morphing.

HP and Microsoft Corp. today announced a portfolio of four new converged application appliances that fuse applications, infrastructure and productivity tools into a single system. These new microsoft solutions help organizations optimize employee productivity and decision-making, while simplifying the delivery of applications for IT.

Aegis Software offering data integration solutions for your enterprise. We collect your enterprise data from different source and integrate them in your enterprise system or platforms through which you can increase your business performance and capabilities.

"Executing external processes from Java is a well-known problem area. It is inheriently platform dependent and requires the developer to know and test for platform specific behaviors, for example using cmd.exe on Windows or limited buffer sizes causing deadlocks. The JRE support for this is very limited, albeit better with the new Java SE 1.5 ProcessBuilder class. Reliably executing external processes can also require knowledge of the environment variables before or after the command is executed. In J2SE 1.1-1.4 there is not support for this, since the method, System.getenv(), for retriving environment variables is deprecated. There are currently several different libraries that for their own purposes have implemented frameworks around Runtime.exec() to handle the various issues outlined above. The proposed project should aim at coordinating and learning from these initatives to create and maintain a simple, reusable and well-tested package. Since some of the more problematic platforms are not readily available, it is my hope that the broad Apache community can be a great help."

When developing a mobile application, you need not focus on the limitations or capabilities of different browsers, as Trinidad enables you to develop applications that function properly on different browser types. The Trinidad renderer ensures that the target browser can consume contents correctly. It handles the variations in both browser implementations of HTML, JavaScript, CSS, DOM, XMLHttpRequest and system performance. For example, if a browser does not support XMLHttpRequest and is incapable of posting a partial page request to a server, support for AJAX enables the application to revert automatically to a full page submit so that the same page functions whether the browser supports XMLHttpRequest or not. Furthermore, if the target browser does no support JavaScript Trinidad will automatically render contents that work on HTML by removing all dependencies on JavaScript.

"http://www.atompub.org/ defines a simple interface over HTTP to publish and subscribe to artifacts (files) and collections of artifacts (services/packages). AtomPub interface serves following purposes: 1: provide "feeds" for people/systems to monitor for changes: For example, user subscribes to a feed which lists contents of package or user subscribes to feed which lists changed contents in a package 2. provide the default remote api to push/pull content and meta data from the repository. This allows other applications to integrate with Guvnor by accessing repository content via atom pub programmatically."

Cliff Click from Azul Systems talks about JVM services. Appx 45 mins.

This article is about how to setup remote debugging in eclipse which is pretty important for development across operating system.

Quartz is a full-featured, open source job scheduling service that can be integrated with, or used along side virtually any Java EE or Java SE application - from the smallest stand-alone application to the largest e-commerce system. Quartz can be used to create simple or complex schedules for executing tens, hundreds, or even tens-of-thousands of jobs; jobs whose tasks are defined as standard Java components that may execute virtually anything you may program them to do. The Quartz Scheduler includes many enterprise-class features, such as JTA transactions and clustering. Quartz is freely usable, licensed under the Apache 2.0 license.