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.factory.util; 019 020 import java.lang.reflect.Method; 021 import java.lang.reflect.Modifier; 022 import java.util.Collection; 023 import java.util.HashMap; 024 import java.util.HashSet; 025 import java.util.Iterator; 026 import java.util.Map; 027 import java.util.Set; 028 029 /** 030 * A useful superclass for {@link ProxyClassGenerator} implementations. 031 * 032 * @author James Carman 033 * @since 1.0 034 */ 035 public abstract class AbstractProxyClassGenerator implements ProxyClassGenerator 036 { 037 //---------------------------------------------------------------------------------------------------------------------- 038 // Static Methods 039 //---------------------------------------------------------------------------------------------------------------------- 040 041 /** 042 * Returns all methods that a proxy class must implement from the proxy interfaces. This method makes sure there 043 * are no method signature clashes. For methods with the same signature (name and parameter types), the one 044 * encountered first will be returned in the result. Final methods are also excluded from the result. 045 * 046 * @param proxyClasses the interfaces the proxy class must implement 047 * @return all methods that the proxy class must implement 048 */ 049 public static Method[] getImplementationMethods( Class[] proxyClasses ) 050 { 051 final Map signatureMethodMap = new HashMap(); 052 final Set finalizedSignatures = new HashSet(); 053 for( int i = 0; i < proxyClasses.length; i++ ) 054 { 055 Class proxyInterface = proxyClasses[i]; 056 final Method[] methods = proxyInterface.getMethods(); 057 for( int j = 0; j < methods.length; j++ ) 058 { 059 final MethodSignature signature = new MethodSignature( methods[j] ); 060 if( Modifier.isFinal( methods[j].getModifiers() ) ) 061 { 062 finalizedSignatures.add( signature ); 063 } 064 else if( !signatureMethodMap.containsKey( signature ) ) 065 { 066 signatureMethodMap.put( signature, methods[j] ); 067 } 068 } 069 } 070 final Collection resultingMethods = signatureMethodMap.values(); 071 for( Iterator i = finalizedSignatures.iterator(); i.hasNext(); ) 072 { 073 MethodSignature signature = ( MethodSignature ) i.next(); 074 resultingMethods.remove( signatureMethodMap.get( signature ) ); 075 } 076 return ( Method[] ) resultingMethods.toArray( new Method[resultingMethods.size()] ); 077 } 078 } 079