Mon, 28 Feb 2011 11:48:53 +0000
7015430: Incorrect thrown type determined for unchecked invocations
Summary: Thrown types do not get updated after 15.12.2.8, and do not get erased as per 15.12.2.6
Reviewed-by: jjg, dlsmith
1 /*
2 * Copyright (c) 2007, 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 */
26 package com.sun.tools.javac.util;
28 import java.io.Closeable;
29 import java.io.IOException;
30 import java.lang.reflect.Field;
31 import java.net.URL;
32 import java.net.URLClassLoader;
33 import java.util.ArrayList;
34 import java.util.jar.JarFile;
36 /**
37 * A URLClassLoader that also implements Closeable.
38 * Reflection is used to access internal data structures in the URLClassLoader,
39 * since no public API exists for this purpose. Therefore this code is somewhat
40 * fragile. Caveat emptor.
41 * @throws Error if the internal data structures are not as expected.
42 *
43 * <p><b>This is NOT part of any supported API.
44 * If you write code that depends on this, you do so at your own risk.
45 * This code and its internal interfaces are subject to change or
46 * deletion without notice.</b>
47 */
48 public class CloseableURLClassLoader
49 extends URLClassLoader implements Closeable {
50 public CloseableURLClassLoader(URL[] urls, ClassLoader parent) throws Error {
51 super(urls, parent);
52 try {
53 getLoaders(); //proactive check that URLClassLoader is as expected
54 } catch (Throwable t) {
55 throw new Error("cannot create CloseableURLClassLoader", t);
56 }
57 }
59 /**
60 * Close any jar files that may have been opened by the class loader.
61 * Reflection is used to access the jar files in the URLClassLoader's
62 * internal data structures.
63 * @throws java.io.IOException if the jar files cannot be found for any
64 * reson, or if closing the jar file itself causes an IOException.
65 */
66 @Override
67 public void close() throws IOException {
68 try {
69 for (Object l: getLoaders()) {
70 if (l.getClass().getName().equals("sun.misc.URLClassPath$JarLoader")) {
71 Field jarField = l.getClass().getDeclaredField("jar");
72 JarFile jar = (JarFile) getField(l, jarField);
73 if (jar != null) {
74 //System.err.println("CloseableURLClassLoader: closing " + jar);
75 jar.close();
76 }
77 }
78 }
79 } catch (Throwable t) {
80 IOException e = new IOException("cannot close class loader");
81 e.initCause(t);
82 throw e;
83 }
84 }
86 private ArrayList<?> getLoaders()
87 throws NoSuchFieldException, IllegalArgumentException, IllegalAccessException
88 {
89 Field ucpField = URLClassLoader.class.getDeclaredField("ucp");
90 Object urlClassPath = getField(this, ucpField);
91 if (urlClassPath == null)
92 throw new AssertionError("urlClassPath not set in URLClassLoader");
93 Field loadersField = urlClassPath.getClass().getDeclaredField("loaders");
94 return (ArrayList<?>) getField(urlClassPath, loadersField);
95 }
97 private Object getField(Object o, Field f)
98 throws IllegalArgumentException, IllegalAccessException {
99 boolean prev = f.isAccessible();
100 try {
101 f.setAccessible(true);
102 return f.get(o);
103 } finally {
104 f.setAccessible(prev);
105 }
106 }
108 }