The Web services for Java 2 Platform, Enterprise Edition (J2EE) specification defines the programming model and run-time architecture for implementing Web services based on the Java language. Another name for the Web Services for J2EE specification is the Java Specification Requirements (JSR) 109. The specification includes open standards for developing and implementing Web services.
Version 6.0 uses Web Services for J2EE 1.1 as the standard for developing and implementing Web services. Web Services for J2EE 1.1 is one of the Web service APIs available in J2EE 1.4.
The Web Services for J2EE specification focuses on Extensible Markup Language (XML) remote procedure call (RPC) and the Java language, including representing XML-based interface definitions in the Java language; Java language definitions in XML-based definition languages, such as SOAP, and assembling.
The J2EE technology can be integrated with Web services in a variety of ways. J2EE components, for example, JavaBeans and enterprise beans, can be exposed as Web services. These services can be accessed by clients written in Java code or by existing Web service clients that are not written in Java code. J2EE components can also act as Web service clients.
The Web Services for J2EE specification is the preferred platform for Web-based programming because it provides open standards allowing different types of languages, operating systems and software to communicate seamlessly through the Internet.
For a Java application to act as Web service client, a mapping between the Web Services Description Language (WSDL) file and the Java application must exist. The mapping is defined by the Java API for XML-based RPC (JAX-RPC) specification.
You can use a Java component to implement a Web service by specifying the component interface and binding information in the WSDL file and designing the application server infrastructure to accept the service request.
This entire process encompassed is based on the Web Services for J2EE specification. The specification brings with it the webservices.xml deployment descriptor specifically for Web services. You are responsible for providing various elements to the deployment descriptor, including:
The EJB 2.1 specification also states that for a Web service developed from a session bean, the EJB deployment descriptor, ejb-jar.xml, must contain the service-endpoint element. The service-endpoint value must be the same as that stated in the webservices.xml deployment descriptor. To learn more about the EJB 2.1 specification see Enterprise beans: Resources for learning.
To review the entire Web Services for J2EE specification, see Web services: Resources for learning.
Related concepts
JAX-RPC
Related reference
Web services: Resources for learning
Enterprise beans: Resources for learning