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"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."

"AtomServer is a generic data store implemented as a RESTful web service. It is designed as a GData-style Atom Store. It is based on the following concepts and protocols; REST. REST is a design pattern. It's not a technology like SOAP or HTTP. REST is a proven design pattern for building loosely-coupled, highly-scalable applications. There are important benefits to sticking to the REST design pattern; Simple. REST is incredibly simple to define. There are just a handful of principles and well defined semantics associated with it. Scalable. REST leads to a very scalable solution by promoting a stateless protocol and allowing state to be distributed across the web. Layered. REST allows any number of intermediaries, such as proxies, gateways, and firewalls. Ultimately REST is just a web site, albeit one that adheres to a design pattern, so one can easily layer aspects such as Security, Compression, etc. on an as needed basis. Atom. Fundamentally, Atom is an XML vocabulary for describing lists of timestamped entries. These entries can be anything, although because Atom was originally conceived to replace RSS, Atom lists are Feeds, and the items in the lists are Entries. Atom is a RESTful protocol. AtomServer stands on the shoulders of giants. It is built on top of several open source projects - most notably, Apache Abdera (a Java-based Atom Publishing framework) and Spring. AtomServer is an Atom Store. Thus, it requires a relational database to run. AtomServer currently supports; PostgresSQL, SQLServer, and HSQLDB. Using HSQLDB, AtomServer requires zero configuration and can run out-of-the-box. While this configuration is suitable for many applications, those that see significant load will likely require a database with better transactional semantics, such as PostgreSQL. AtomServer is easy to use. It deploys as a simple WAR file into any Servlet container. Or alternately, can be used out-of-the-box as a standalone server, running with

"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."

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

The Apache Software Foundation has resigned its seat on the Java SE/EE Executive Committee. Apache has served on the EC for the past 10 years, winning the JCP "Member of the Year" award 4 times, and recently was ratified for another term with support from 95% of the voting community. Further, the project communities of the ASF, home to Apache Tomcat, Ant, Xerces, Geronimo, Velocity and nearly a 100 mainstay java components have implemented countless JSRs and serve on and contribute to many of the JCPs technical expert groups. We'd like to provide some explanation to the community as to why we're taking this significant step.

Weld is the reference implementation (RI) for JSR-299: Java Contexts and Dependency Injection for the Java EE platform (CDI). CDI is the Java standard for dependency injection and contextual lifecycle management, led by Gavin King for Red Hat, Inc. and is a Java Community Process (JCP) specification that integrates cleanly with the Java EE platform. Any Java EE 6-compliant application server provides support for JSR-299 (even the web profile). Weld and the JSR-299 TCK (Technology Compatibility Kit) are developed here at seamframework.org. Both are licensed under the Apache License, Version 2.0.

AspectJ is an aspect-oriented extension created at PARC for the Java programming language. It is available in Eclipse Foundation open-source projects, both stand-alone and integrated into Eclipse. AspectJ has become the widely used de-facto standard for AOP by emphasizing simplicity and usability for end users. It uses Java-like syntax and has included IDE integrations for displaying crosscutting structure since its initial public release in 2001. In this article we will describe how we can use AspectJ to do the logging job for all methods parameters and methods return values in a Java application

"JAnnocessor is a new open-source framework for powerful, flexible, yet easy processing of annotated Java code. Its main purpose is compile-time, annotation-driven source code generation in a declarative and customizable fashion. JAnnocessor is built on top of Java APT, encapsulating the Java source code model in a rich and convenient high-level domain model that serves as a good target for expressive matching and transformation. Finally, a template engine is used for customizable template-based source code generation. Having simplicity and productivity in mind, JAnnocessor has many useful features that make it enjoyable: smart imports organization, logging delegation, graphical UI for real-time debug, hot swap of processors and templates, as well as out-of-the-box common annotations, processors and templates."

Joomla is best option for CMS development. Joomla is widely popular for dynamic web application with using its CMS. Many hosting providers offer joomla web hosting plans for joomla based webstie. This article provides you information about how to find best hosting providers for your joomla based website.

YAML is a data serialization format designed for human readability and interaction with scripting languages. SnakeYAML is a YAML parser and emitter for the Java programming language. SnakeYAML features a complete YAML 1.1 parser. In particular, SnakeYAML can parse all examples from the specification. Unicode support including UTF-8/UTF-16 input/output. high-level API for serializing and deserializing native Java objects. support for all types from the YAML types repository. relatively sensible error messages.

Some of the common questions relating to cyclomatic complexity are "How does my code compare to others?" and "What is a good number for a particular class?" The iPlasma project answers these questions (see Resources). iPlasma is a platform, created as a university project in Romania, for quality assessment of object-oriented design. It generates a pyramid, showing key metrics for your project along with comparisons to industry-standard ranges for those numbers.

"There are pros and cons for considering validation as business logic, and Spring offers a design for validation (and data binding) that does not exclude either one of them. Specifically validation should not be tied to the web tier, should be easy to localize and it should be possible to plug in any validator available. Considering the above, Spring has come up with a Validator interface that is both basic ands eminently usable in every layer of an application. Data binding is useful for allowing user input to be dynamically bound to the domain model of an application (or whatever objects you use to process user input). Spring provides the so-called DataBinder to do exactly that. The Validator and the DataBinder make up the validation package, which is primarily used in but not limited to the MVC framework. The BeanWrapper is a fundamental concept in the Spring Framework and is used in a lot of places. However, you probably will not have the need to use the BeanWrapper directly. Because this is reference documentation however, we felt that some explanation might be in order. We will explain the BeanWrapper in this chapter since, if you were going to use it at all, you would most likely do so when trying to bind data to objects. Spring's DataBinder and the lower-level BeanWrapper both use PropertyEditors to parse and format property values. The PropertyEditor concept is part of the JavaBeans specification, and is also explained in this chapter. Spring 3 introduces a "core.convert" package that provides a general type conversion facility, as well as a higher-level "format" package for formatting UI field values. These new packages may be used as simpler alternatives to PropertyEditors, and will also be discussed in this chapter."

"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

The goal of the Eclipse Scout project is making it easy to build distributed enterprise applications based on the Eclipse platform. It consists of a runtime framework providing transparent service communication between the client and backend part and is shipped with a rich set of common user interface components. The user interface is not built for a particular rendering technology but it encapsulates the core functionality into a headless model. GUI factories are available for rendering the client model into a particular target UI platform. SWT and Swing are supported out of the box and an AJAX GUI factory could be easily added. Developing Scout applications is supported by the Scout SDK, a plug-in set built on top of Eclipse PDE and Eclipse JDT. The Scout SDK works directly on the bare Java resources and assists the development task by providing an augmented view on the underlying Java code. Additionally, it comes with a rich set of wizards and operations for modifying the Scout application project just by editing the underlying Java code. There is no meta-data required. Hence a developer can switch between editing resources using Eclipse's standard editors and leveraging the features of Scout SDK at any point in time. Eclipse Scout can be used to create multi-tier client/server applications, standalone client applications or OSGi-based server applications. Basically, there are three main advantages when choosing Scout as your framework for building such applications. First, the Scout runtime is service oriented by design. Almost every functionality is provided as an OSGi service. Every OSGi bundle may make use of them. Second, Scout provides a rich set of UI elements being uncoupled from a particular GUI technology. And third, building distributed client/server applications is as easy as if both parts would run within the same local JVM.

Interview Questions on Java Swing for GUI Programmer.Swing is a difficult technology to learn and for programming GUI in swing you need a bit of expertize which makes demand of Swing developer quite high and same time make interview process for swing developer quite challenging and testing. Adding to it there are not much swing interview questions available on net. This article solve this problem by providing some of the best swing interview questions asked in banks. these questions are practical , genuine and same time challenging.

"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."

Bndtools is an Eclipse-based development environment for OSGi bundles and applications that focuses on: Ease of use and a rapid development lifecycle; Encouraging OSGi best practices; Producing accurate bundle metadata to maximise re-usability; Integration with offline build tools and users of other IDEs. See Features for a summary of Bndtools features. Bndtools is based on Bnd, the powerful bundle tool created by Peter Kriens. Please read Why Bndtools? to learn why Bndtools has been created and why you should use it for OSGi development in Eclipse.

"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."