001 /*
002 * Licensed to the Apache Software Foundation (ASF) under one or more
003 * contributor license agreements. See the NOTICE file distributed with
004 * this work for additional information regarding copyright ownership.
005 * The ASF licenses this file to You under the Apache License, Version 2.0
006 * (the "License"); you may not use this file except in compliance with
007 * the License. You may obtain a copy of the License at
008 *
009 * http://www.apache.org/licenses/LICENSE-2.0
010 *
011 * Unless required by applicable law or agreed to in writing, software
012 * distributed under the License is distributed on an "AS IS" BASIS,
013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014 * See the License for the specific language governing permissions and
015 * limitations under the License.
016 */
017
018 package org.apache.commons.proxy.interceptor;
019
020 import org.apache.commons.proxy.Invocation;
021 import org.apache.commons.proxy.Interceptor;
022
023 /**
024 * Decorates another <code>MethodInterceptor</code> by only calling it if the method is accepted by the supplied
025 * <code>MethodFilter</code>.
026 *
027 * @author James Carman
028 * @since 1.0
029 */
030 public class FilteredInterceptor implements Interceptor
031 {
032 //----------------------------------------------------------------------------------------------------------------------
033 // Fields
034 //----------------------------------------------------------------------------------------------------------------------
035
036 private final Interceptor inner;
037 private final MethodFilter filter;
038
039 //----------------------------------------------------------------------------------------------------------------------
040 // Constructors
041 //----------------------------------------------------------------------------------------------------------------------
042
043 public FilteredInterceptor( Interceptor inner, MethodFilter filter )
044 {
045 this.inner = inner;
046 this.filter = filter;
047 }
048
049 //----------------------------------------------------------------------------------------------------------------------
050 // MethodInterceptor Implementation
051 //----------------------------------------------------------------------------------------------------------------------
052
053 public Object intercept( Invocation invocation ) throws Throwable
054 {
055 if( filter.accepts( invocation.getMethod() ) )
056 {
057 return inner.intercept( invocation );
058 }
059 else
060 {
061 return invocation.proceed();
062 }
063 }
064 }
065