1 /*
2  * Javassist, a Java-bytecode translator toolkit.
3  * Copyright (C) 1999-2007 Shigeru Chiba. All Rights Reserved.
4  *
5  * The contents of this file are subject to the Mozilla Public License Version
6  * 1.1 (the "License"); you may not use this file except in compliance with
7  * the License.  Alternatively, the contents of this file may be used under
8  * the terms of the GNU Lesser General Public License Version 2.1 or later.
9  *
10  * Software distributed under the License is distributed on an "AS IS" basis,
11  * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
12  * for the specific language governing rights and limitations under the
13  * License.
14  */
15 
16 package javassist.util.proxy;
17 
18 import java.lang.reflect.Method;
19 
20 /**
21  * The interface implemented by the invocation handler of a proxy
22  * instance.
23  *
24  * @see ProxyFactory#setHandler(MethodHandler)
25  */
26 public interface MethodHandler {
27     /**
28      * Is called when a method is invoked on a proxy instance associated
29      * with this handler.  This method must process that method invocation.
30      *
31      * @param self          the proxy instance.
32      * @param thisMethod    the overridden method declared in the super
33      *                      class or interface.
34      * @param proceed       the forwarder method for invoking the overridden
35      *                      method.  It is null if the overridden mehtod is
36      *                      abstract or declared in the interface.
37      * @param args          an array of objects containing the values of
38      *                      the arguments passed in the method invocation
39      *                      on the proxy instance.  If a parameter type is
40      *                      a primitive type, the type of the array element
41      *                      is a wrapper class.
42      * @return              the resulting value of the method invocation.
43      *
44      * @throws Throwable    if the method invocation fails.
45      */
invoke(Object self, Method thisMethod, Method proceed, Object[] args)46     Object invoke(Object self, Method thisMethod, Method proceed,
47                   Object[] args) throws Throwable;
48 }
49