/* | |
* 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 org.apache.commons.proxy2.invoker; | |
import org.apache.commons.proxy2.Invoker; | |
import org.apache.commons.proxy2.ProxyUtils; | |
import java.io.Serializable; | |
import java.lang.reflect.Method; | |
/** | |
* An {@link Invoker} implementation which merely returns null for all method invocations. This class is | |
* useful for scenarios where the "null object" design pattern is needed. | |
* | |
* @author James Carman | |
* @since 1.0 | |
*/ | |
public class NullInvoker implements Invoker, Serializable | |
{ | |
/** Serialization version */ | |
private static final long serialVersionUID = 1L; | |
/** | |
* Statically available instance. | |
*/ | |
public static final NullInvoker INSTANCE = new NullInvoker(); | |
//********************************************************************************************************************** | |
// Invoker Implementation | |
//********************************************************************************************************************** | |
/** | |
* {@inheritDoc} | |
*/ | |
public Object invoke( Object proxy, Method method, Object[] args ) throws Throwable | |
{ | |
final Class<?> returnType = method.getReturnType(); | |
return ProxyUtils.nullValue(returnType); | |
} | |
} |