1 /* CombinedClassLoader.java -- Multiple class loader support for proxy. 2 Copyright (C) 2006 Free Software Foundation, Inc. 3 4 This file is part of GNU Classpath. 5 6 GNU Classpath is free software; you can redistribute it and/or modify 7 it under the terms of the GNU General Public License as published by 8 the Free Software Foundation; either version 2, or (at your option) 9 any later version. 10 11 GNU Classpath is distributed in the hope that it will be useful, but 12 WITHOUT ANY WARRANTY; without even the implied warranty of 13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 14 General Public License for more details. 15 16 You should have received a copy of the GNU General Public License 17 along with GNU Classpath; see the file COPYING. If not, write to the 18 Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 19 02110-1301 USA. 20 21 Linking this library statically or dynamically with other modules is 22 making a combined work based on this library. Thus, the terms and 23 conditions of the GNU General Public License cover the whole 24 combination. 25 26 As a special exception, the copyright holders of this library give you 27 permission to link this library with independent modules to produce an 28 executable, regardless of the license terms of these independent 29 modules, and to copy and distribute the resulting executable under 30 terms of your choice, provided that you also meet, for each linked 31 independent module, the terms and conditions of the license of that 32 module. An independent module is a module which is not derived from 33 or based on this library. If you modify this library, you may extend 34 this exception to your version of the library, but you are not 35 obligated to do so. If you do not wish to do so, delete this 36 exception statement from your version. */ 37 38 39 package gnu.java.rmi.server; 40 41 import java.io.IOException; 42 import java.net.URL; 43 import java.util.Collection; 44 import java.util.Enumeration; 45 import java.util.Iterator; 46 import java.util.ArrayList; 47 48 /** 49 * This class supports the multiple class loaders to load the resources. It is 50 * used for constructing proxy classes that implement interfaces, loaded by 51 * the several different class loaders. 52 * 53 * @author Audrius Meskauskas (AudriusA@Bioinformatics.org) 54 */ 55 public class CombinedClassLoader extends ClassLoader 56 { 57 /** 58 * The class loader array. 59 */ 60 ClassLoader[] loaders; 61 62 /** 63 * Create a new combined class loader that uses the given collection of 64 * loaders to load the classes and resources. The loader order is equal to 65 * the order, returned by the collection interator. The duplicate loaders 66 * are discarded and the system class loader is added as the last loader. 67 * 68 * @param a_loaders the loadery collection (may contain duplicate instances 69 * that will be discarded. 70 */ CombinedClassLoader(Collection a_loaders)71 public CombinedClassLoader(Collection a_loaders) 72 { 73 ArrayList sLoaders = new ArrayList(a_loaders.size()); 74 75 Iterator iter = a_loaders.iterator(); 76 Object cl; 77 while (iter.hasNext()) 78 { 79 cl = iter.next(); 80 if (cl!=null && !sLoaders.contains(cl)) 81 sLoaders.add(cl); 82 } 83 84 loaders = new ClassLoader[sLoaders.size()]; 85 86 for (int i = 0; i < loaders.length; i++) 87 loaders[i] = (ClassLoader) sLoaders.get(i); 88 } 89 90 /** 91 * Find the class with the given name. 92 */ findClass(String name)93 protected Class findClass(String name) throws ClassNotFoundException 94 { 95 for (int i = 0; i < loaders.length; i++) 96 { 97 try 98 { 99 return loaders[i].loadClass(name); 100 } 101 catch (ClassNotFoundException e) 102 { 103 // try another. 104 } 105 } 106 return super.findClass(name); 107 } 108 109 /** 110 * Find resource with the given name. 111 */ findResource(String name)112 protected URL findResource(String name) 113 { 114 for (int i = 0; i < loaders.length; i++) 115 { 116 URL resource = loaders[i].getResource(name); 117 if (resource != null) 118 return resource; 119 } 120 return super.findResource(name); 121 } 122 123 /** 124 * Find resources with the given name. 125 */ findResources(String name)126 protected Enumeration findResources(String name) throws IOException 127 { 128 for (int i = 0; i < loaders.length; i++) 129 { 130 Enumeration resource = loaders[i].getResources(name); 131 if (resource != null) 132 return resource; 133 } 134 return super.findResources(name); } 135 } 136