"SOAP up the Bean"

XML
The lesson begins with the understanding of XML (extensible Markup Language). It is basically a markup language for documents containing structured information. XML is different from HTML. In HTML , both the tag semantics and the tag set are fixed.An h1 is always a first level heading and the tag ati.product.code is meaningless. The W3C, in conjunction with browser vendors and the WWW community, is constantly working to extend the definition of HTML to allow new tags to keep pace with changing technology and to bring variations in presentation (stylesheets) to the Web.

In XML, it specifies neither semantics nor a tag set. In fact XML is defined as a meta-language for describing markup languages. On other words, XML provides a facility to define tags and the structural relationships between them. Since there's no predefined tag set, there can't be any preconceived semantics. All of the semantics of an XML document will either be defined by the applications that process them or by stylesheets.

To apprecitate XML, it is important to understand the way it is created. It was created so that richly structured document could be used over the web.On the other hand,XML is not designed to replace SGML. XML is designed to deliver structured content over the web , some of the very features it lack to make this practical , make SGML a more satisfactory solution for the creation and long time storage of complex documents. Hence, most organization had filtered SGML to XML to produce a standard procedure for web delivery.

SOAP - Simple Object Acess Protocol
It is a protocal for exchanging XML-based messages over computer networks normally using HTTP/HTTPS.It forms the foundation layer of the web services stack , providing a basic messaging framework that more abstract layers can build on.

Advantages:
1) Using SOAP over HTTP allows for easier communication behind proxies and firewalls than previous remote execution technology. This is because the common port-80 is opened. SOAP is versatile to allow the use of different transport protocols.
Weaknesses
1) When relying on HTTP as a transport protocol and not using WS-addressing or an ESB the roles of the interacting parties are fixed. Only one party (the client) can use the services of the other. Developers must use polling instead of notification in these common cases.
2) Many SOAP implementations limit the amount of data that can be sent.

JAVA BEAN
It is a portable, platform-independent software component model that allows developers to wrote reusable components once and run them in anywhere. Beans are Java classes that can be manipulated in a visual builder tools and view as a component. When any Java class that adheres to property and event interface conventions, it is known as a Bean.