1 /*
2 * Copyright (c) 1997, 2012, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation. Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25
26 package com.sun.tools.internal.xjc.api.util;
27
28 import java.io.ByteArrayOutputStream;
29 import java.io.IOException;
30 import java.io.InputStream;
31 import java.io.File;
32 import java.net.URL;
33 import java.net.URLClassLoader;
34 import java.net.MalformedURLException;
35
36 import com.sun.istack.internal.Nullable;
37
38 /**
39 * {@link ClassLoader} that loads Annotation Processing and specified classes
40 * both into the same classloader, so that they can reference each other.
41 *
42 * @author Bhakti Mehta
43 * @since 2.0 beta
44 */
45 public final class ApClassLoader extends URLClassLoader {
46 /**
47 * List of package prefixes we want to mask the
48 * parent classLoader from loading
49 */
50 private final String[] packagePrefixes;
51
52 /**
53 *
54 * @param packagePrefixes
55 * The package prefixes that are forced to resolve within this class loader.
56 * @param parent
57 * The parent class loader to delegate to. Null to indicate bootstrap classloader.
58 */
59 public ApClassLoader(@Nullable ClassLoader parent, String[] packagePrefixes) throws ToolsJarNotFoundException {
60 super(getToolsJar(parent),parent);
61 if(getURLs().length==0)
62 // if tools.jar was found in our classloader, no need to create
63 // a parallel classes
64 this.packagePrefixes = new String[0];
65 else
66 this.packagePrefixes = packagePrefixes;
67 }
68
69 public Class loadClass(String className) throws ClassNotFoundException {
70 for( String prefix : packagePrefixes ) {
71 if (className.startsWith(prefix) ) {
72 // we need to load those classes in this class loader
73 // without delegation.
74 return findClass(className);
75 }
76 }
77
78 return super.loadClass(className);
79
80 }
81
82 protected Class findClass(String name) throws ClassNotFoundException {
83
84 StringBuilder sb = new StringBuilder(name.length() + 6);
85 sb.append(name.replace('.','/')).append(".class");
86
87 InputStream is = getResourceAsStream(sb.toString());
88 if (is==null)
89 throw new ClassNotFoundException("Class not found" + sb);
90
91 try {
92 ByteArrayOutputStream baos = new ByteArrayOutputStream();
93 byte[] buf = new byte[1024];
94 int len;
95 while((len=is.read(buf))>=0)
96 baos.write(buf,0,len);
97
98 buf = baos.toByteArray();
99
100 // define package if not defined yet
101 int i = name.lastIndexOf('.');
102 if (i != -1) {
103 String pkgname = name.substring(0, i);
104 Package pkg = getPackage(pkgname);
105 if(pkg==null)
106 definePackage(pkgname, null, null, null, null, null, null, null);
107 }
108
109 return defineClass(name,buf,0,buf.length);
110 } catch (IOException e) {
111 throw new ClassNotFoundException(name,e);
112 } finally {
113 try {
114 is.close();
115 } catch (IOException ioe) {
116 //ignore
117 }
118 }
119 }
120
121 /**
122 * Returns a class loader that can load classes from JDK tools.jar.
123 * @param parent
124 */
125 private static URL[] getToolsJar(@Nullable ClassLoader parent) throws ToolsJarNotFoundException {
126
127 try {
128 Class.forName("com.sun.tools.javac.Main", false, parent);
129 return new URL[0];
130 // we can already load them in the parent class loader.
131 // so no need to look for tools.jar.
132 // this happens when we are run inside IDE/Ant, or
133 // in Mac OS.
134 } catch (ClassNotFoundException e) {
135 // otherwise try to find tools.jar
136 }
137
138 File jreHome = new File(System.getProperty("java.home"));
139 File toolsJar = new File( jreHome.getParent(), "lib/tools.jar" );
140
141 if (!toolsJar.exists()) {
142 throw new ToolsJarNotFoundException(toolsJar);
143 }
144
145 try {
146 return new URL[]{toolsJar.toURL()};
147 } catch (MalformedURLException e) {
148 // impossible
149 throw new AssertionError(e);
150 }
151 }
152 }