40.2. Create a Provider Implementation Class

Overview

The fundamental prerequisite for using provider mode is to define a custom Provider<> class that implements the invoke() method. In fact, the sole purpose of this class is to provide runtime type information for Apache CXF: the invoke() method never gets called!
By implementing the provider class in the way shown here, you are merely indicating to the Apache CXF runtime that the WS endpoint should operate in in PAYLOAD mode and the type of the message PAYLOAD should be SAXSource.

The SAXSourceService provider class

The definition of the provider class is relatively short and the complete definition of the customer provider class, SAXSourceService, is as follows: 
// Java
package com.fusesource.customerwscamelcxfprovider;

import javax.xml.transform.sax.SAXSource;
import javax.xml.ws.Provider;
import javax.xml.ws.Service.Mode;
import javax.xml.ws.ServiceMode;
import javax.xml.ws.WebServiceProvider;

@WebServiceProvider()
@ServiceMode(Mode.PAYLOAD)
public class SAXSourceService implements Provider<SAXSource> 
{
  public SAXSource invoke(SAXSource t) {
    throw new UnsupportedOperationException("Not supported yet.");
  }
}
The customer provider class, SAXSourceService, must be annotated by the @WebServiceProvider annotation to mark it as a provider class and can be optionally annotated by the @ServiceMode annotation to select PAYLOAD mode.