/*
 * Copyright (c) 2009, 2015, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 * or visit www.oracle.com if you need additional information or have any
 * questions.
 */

package javax.xml.ws.spi;

import javax.xml.ws.WebServiceContext;
import javax.xml.ws.WebServiceFeature;
import java.lang.reflect.Method;
import java.lang.reflect.InvocationTargetException;

Invoker hides the detail of calling into application endpoint implementation. Container hands over an implementation of Invoker to JAX-WS runtime, and jax-ws runtime calls invoke for a web service invocation. Finally, Invoker does the actual invocation of web service on endpoint instance. Container also injects the provided WebServiceContext and takes care of invoking javax.annotation.PostConstruct methods, if present, on the endpoint implementation. 
Author:
Jitendra Kotamraju
See Also:
Provider.createEndpoint(String, Class<?>, Invoker, WebServiceFeature...)
Since:
1.7, JAX-WS 2.2/**
 * Invoker hides the detail of calling into application endpoint
 * implementation. Container hands over an implementation of Invoker
 * to JAX-WS runtime, and jax-ws runtime calls {@link #invoke}
 * for a web service invocation. Finally, Invoker does the actual
 * invocation of web service on endpoint instance.
 *
 * Container also injects the provided {@code WebServiceContext} and takes
 * care of invoking {@code javax.annotation.PostConstruct} methods,
 * if present, on the endpoint implementation.
 *
 * @see Provider#createEndpoint(String, Class, Invoker, WebServiceFeature...)
 * @author Jitendra Kotamraju
 * @since 1.7, JAX-WS 2.2
 */

public abstract class Invoker {

    
JAX-WS runtimes calls this method to ask container to inject WebServiceContext on the endpoint instance. The WebServiceContext object uses thread-local information to return the correct information during the actual endpoint invocation regardless of how many threads are concurrently being used to serve requests. 
Params:
webServiceContext – a holder for MessageContext
Throws:
IllegalAccessException – if the injection done
        by reflection API throws this exception
IllegalArgumentException – if the injection done
        by reflection API throws this exception
InvocationTargetException – if the injection done
        by reflection API throws this exception/**
     * JAX-WS runtimes calls this method to ask container to inject
     * WebServiceContext on the endpoint instance. The
     * {@code WebServiceContext} object uses thread-local information
     * to return the correct information during the actual endpoint invocation
     * regardless of how many threads are concurrently being used to serve
     * requests.
     *
     * @param webServiceContext a holder for MessageContext
     * @throws IllegalAccessException if the injection done
     *         by reflection API throws this exception
     * @throws IllegalArgumentException if the injection done
     *         by reflection API throws this exception
     * @throws InvocationTargetException if the injection done
     *         by reflection API throws this exception
     */
    public abstract void inject(WebServiceContext webServiceContext)
    throws IllegalAccessException, IllegalArgumentException, InvocationTargetException;

    
JAX-WS runtime calls this method to do the actual web service invocation on endpoint instance. The injected WebServiceContext.getMessageContext() gives the correct information for this invocation. 
Params:
m – Method to be invoked on the service
args – Method arguments
Throws:
IllegalAccessException – if the invocation done
        by reflection API throws this exception
IllegalArgumentException – if the invocation done
        by reflection API throws this exception
InvocationTargetException – if the invocation done
        by reflection API throws this exception
See Also:
Method.invoke
Returns:
return value of the method/**
     * JAX-WS runtime calls this method to do the actual web service
     * invocation on endpoint instance. The injected
     * {@code WebServiceContext.getMessageContext()} gives the correct
     * information for this invocation.
     *
     * @param m Method to be invoked on the service
     * @param args Method arguments
     * @return return value of the method
     * @throws IllegalAccessException if the invocation done
     *         by reflection API throws this exception
     * @throws IllegalArgumentException if the invocation done
     *         by reflection API throws this exception
     * @throws InvocationTargetException if the invocation done
     *         by reflection API throws this exception

     * @see Method#invoke
     */
    public abstract Object invoke(Method m, Object... args)
    throws  IllegalAccessException, IllegalArgumentException, InvocationTargetException;

}