Jakarta XML RPC

Jakarta XML RPC allows a Jakarta EE application to invoke a Java-based web service with a known description while still being consistent with its WSDL description. JAX-RPC is one of the Java XML programming APIs. It can be seen as method invocation|Java RMI]s over web services. JAX-RPC 2.0 was renamed JAX-WS 2.0. JAX-RPC 1 is deprecated with Java EE 6. The JAX-RPC service utilizes W3C standards like WSDL.
The core API classes are located in the Java package.

Supports web-based services and clients using RPC or remote procedure calls which are based on XML.
Allow for web service accessibility through Java APIs which in turn allows for communication between different Java applications.
Enables client communication with web service of different language and running on separate platform.

It works as follows:

A Java program executes a method on a stub
The stub executes routines in the JAX-RPC Runtime System
The RS converts the remote method invocation into a SOAP message
The RS transmits the message as an HTTP request

The advantage of such a method is that it allows the Web service to be implemented at server-side as a Servlet or EJB container. Thus, Servlet or EJB applications are made available through Web services.
Jakarta XML RPC was removed from Jakarta EE 9.

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