java.lang.reflect.InvocationHandler Maven / Gradle / Ivy
/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package java.lang.reflect;
/**
* Implementors of this interface dispatch methods invoked on proxy instances.
*
* @see Proxy
*/
public interface InvocationHandler {
/**
* Handles the method which was originally invoked on the proxy instance. A
* typical usage pattern follows below:
*
*
* public Object invoke(Object proxy, Method method, Object[] args) throws Throwable {
* //do some processing before the method invocation
*
* //invoke the method
* Object result = method.invoke(proxy, args);
*
* //do some processing after the method invocation
* return result;
* }
*
* @param proxy
* the proxy instance on which the method was invoked
* @param method
* the method invoked on the proxy instance
* @param args
* an array of objects containing the parameters passed to the
* method, or {@code null} if no arguments are expected.
* Primitive types are boxed.
*
* @return the result of executing the method. Primitive types are boxed.
*
* @throws Throwable
* the exception to throw from the invoked method on the proxy.
* The exception must match one of the declared exception types
* of the invoked method or any unchecked exception type. If not
* then an {@code UndeclaredThrowableException} is thrown
*/
public Object invoke(Object proxy, Method method, Object[] args) throws Throwable;
}