JBoss Application Server (or JBoss AS) is a free software / open source Java EE-based application server. Because it is Java-based, the JBoss application server is cross-platform, usable on any operating system that Java supports. JBoss AS 4.0 is a Java EE 1.4 application server, with embedded Apache Tomcat 5.5. Any Java Virtual Machine between versions 1.4 and 1.5 is supported. JBoss can run on numerous operating systems including many POSIX platforms (like Linux and Mac OS X), Microsoft Windows and others, as long as a suitable JVM is present.
JBoss AS 4.2 is also a Java EE 1.4 application server, but Enterprise JavaBeans 3.0 is deployed by default. It requires the Java Development Kit version 5. Tomcat 6 is bundled with it.
The next version of JBoss AS 5 is planned to be a Java EE 5 application server
Failover (including sessions)
Distributed caching (using JBoss Cache, a standalone product)
Distributed deployment (farming)
Enterprise Java Beans version 3
Hibernate-integration (for persistence programming;JPA)
Support for J2EE-Web Services like JAX-RPC (Java API for XML for Remote Procedure Call)
Java Message Service integration
JCA (Java Connector Architecture)-integration
JACC (Java Authorization Contract for Containers)-integration
RMI-IIOP (JacORB, alias Java and CORBA)
JTA (Java Transaction API)
SAAJ (SOAP with Attachments API for Java)
JNDI (Java Naming and Directory Interface)
JAAS (Java Authentication and Authorization Service)
The World Wide Web Consortium (W3C) is an international industry consortium dedicated to “leading the Web to its full potential“. It’s led by Tim Berners-Lee, the inventor of the Web. Founded in 1994, the W3C has more than 450 member organizations - including Microsoft, America Online (parent company of Netscape Communications), Apple Inc., Adobe, Sun Microsystems, and a variety of other hardware and software manufacturers, content providers, academic institutions, and telecommunications companies. The Consortium is hosted by three research institutions - MIT in the US, INRIA in Europe, and Keio University in Japan.
Standards for w3c HTML
HTML 4.0 - HyperText Markup Language
HyperText Markup Language (HTML) is widely used on the Web for adding structure to text documents. Browsers interpret these documents, representing the structure in media-specific ways to the user. For example, visual browsers typically display the strong element ( … ) as bold text, while text-to-speech readers might emphasize that text when pronouncing it.
With the help of Cascading Style Sheets (CSS) the author may define how structural elements are to be represented, overriding the browser defaults.
Standards for w3c XHTML
XML 1.0 - Extensible Markup Language
Extensible Markup Language (XML) is a markup language like HTML, but instead of having a single, fixed set of elements, it allows you to define your own - or use a set made by someone else. It even allows using multiple sets within a single document - by using XML namespaces.
Some applications of XML, such as XHTML and MathML, have already become W3C Recommendations. Others are currently W3C Working Drafts.
Style sheet standards, such as CSS and XSL, offer a variety of options for specifying how XML elements are to be rendered. Standards-compliant support for direct rendering of XML is spotty in browsers, so for presenting information to humans, HTML (or XHTML) with CSS-driven styling is the way to go. XML is mostly used for machine-to-machine communication today.
XML is more flexible than HTML, primarily because of the ability to add your own elements and make your own structural systems. This makes it an ideal format for the organization of large quantities of data - it is already in use in many databases and search engines.
XHTML 1.0, 1.1, and Modularization
XHTML 1.0 is a reformulation of HTML as an XML application. XHTML 1.0 can be seen as ideologically coming from HTML 4.01, and being technically stricter because of XML’s influence.
XHTML will display in your browser identically to the equivalent HTML. You might want to use XHTML if there is any chance you’re going to need to reprocess your content, for example to send it to a PDA; XML’s stricter syntax rules make automatic processing of XHTML much easier and cheaper than ordinary HTML.
Ideologically, XHTML 1.0 inherits the following general concepts from HTML 4.01:
That presentation and document formatting should be separated via style sheets
That documents should be made accessible
That documents should be internationalized
XHTML 1.0 also uses the model of three DTDs: Strict, Transitional, and Frameset. This model originally emerged in HTML 4.0 and followed through to HTML 4.01.
Some important technical practices from XML onto XHTML includes:
That all document types are declared via the correct DOCTYPE declaration
That the structure of a conforming document contain the DOCTYPE declaration, an html element with the XHTML namespace declared, a head element including the title element, and a body element
That all elements and attribute names are written in lower case, and that all attribute values are quoted
That all non-empty elements (e.g. p, li) are properly terminated with a closing tag
That all empty elements (e.g. br, hr, img) are properly terminated with a trailing slash
That documents validate against the DTD that is declared