1 /*
2 * Copyright (c) 2014, 2015, 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.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 */
23
24 /*
25 * @test
26 * @bug 8076110
27 * @summary Redefine running methods that have cached resolution errors
28 * @library /testlibrary
29 * @modules java.instrument
30 * java.base/jdk.internal.org.objectweb.asm
31 * @build RedefineClassHelper
32 * @run main RedefineClassHelper
33 * @run main/othervm -javaagent:redefineagent.jar -XX:TraceRedefineClasses=0x600 RedefineRunningMethodsWithResolutionErrors
34 */
35
36 import jdk.internal.org.objectweb.asm.ClassWriter;
37 import jdk.internal.org.objectweb.asm.Label;
38 import jdk.internal.org.objectweb.asm.MethodVisitor;
39 import jdk.internal.org.objectweb.asm.Opcodes;
40
41 import java.lang.reflect.InvocationTargetException;
42
43 public class RedefineRunningMethodsWithResolutionErrors extends ClassLoader implements Opcodes {
44
45 @Override
46 protected Class<?> findClass(String name) throws ClassNotFoundException {
47 if (name.equals("C")) {
48 byte[] b = loadC(false);
49 return defineClass(name, b, 0, b.length);
50 } else {
51 return super.findClass(name);
52 }
53 }
54
55 private static byte[] loadC(boolean redefine) {
56 ClassWriter cw = new ClassWriter(0);
57
58 cw.visit(52, ACC_SUPER | ACC_PUBLIC, "C", null, "java/lang/Object", null);
59 {
60 MethodVisitor mv;
61
62 mv = cw.visitMethod(ACC_PUBLIC | ACC_STATIC, "m", "()V", null, null);
63 mv.visitCode();
64
65 // First time we run we will:
66 // 1) Cache resolution errors
67 // 2) Redefine the class / method
68 // 3) Try to read the resolution errors that were cached
69 //
70 // The redefined method will never run, throw error to be sure
71 if (redefine) {
72 createThrowRuntimeExceptionCode(mv, "The redefined method was called");
73 } else {
74 createMethodBody(mv);
75 }
76 mv.visitMaxs(3, 0);
77 mv.visitEnd();
78 }
79 cw.visitEnd();
80 return cw.toByteArray();
81 }
82
83 private static void createMethodBody(MethodVisitor mv) {
84 Label classExists = new Label();
85
86 // Cache resolution errors
87 createLoadNonExistentClassCode(mv, classExists);
88
89 // Redefine our own class and method
90 mv.visitMethodInsn(INVOKESTATIC, "RedefineRunningMethodsWithResolutionErrors", "redefine", "()V");
91
92 // Provoke the same error again to make sure the resolution error cache works
93 createLoadNonExistentClassCode(mv, classExists);
94
95 // Test passed
96 mv.visitInsn(RETURN);
97
98 mv.visitFrame(F_SAME, 0, new Object[0], 0, new Object[0]);
99 mv.visitLabel(classExists);
100
101 createThrowRuntimeExceptionCode(mv, "Loaded class that shouldn't exist (\"NonExistentClass\")");
102 }
103
104 private static void createLoadNonExistentClassCode(MethodVisitor mv, Label classExists) {
105 Label tryLoadBegin = new Label();
106 Label tryLoadEnd = new Label();
107 Label catchLoadBlock = new Label();
108 mv.visitTryCatchBlock(tryLoadBegin, tryLoadEnd, catchLoadBlock, "java/lang/NoClassDefFoundError");
109
110 // Try to load a class that does not exist to provoke resolution errors
111 mv.visitLabel(tryLoadBegin);
112 mv.visitMethodInsn(INVOKESTATIC, "NonExistentClass", "nonExistentMethod", "()V");
113 mv.visitLabel(tryLoadEnd);
114
115 // No NoClassDefFoundError means NonExistentClass existed, which shouldn't happen
116 mv.visitJumpInsn(GOTO, classExists);
117
118 mv.visitFrame(F_SAME1, 0, new Object[0], 1, new Object[] { "java/lang/NoClassDefFoundError" });
119 mv.visitLabel(catchLoadBlock);
120
121 // Ignore the expected NoClassDefFoundError
122 mv.visitInsn(POP);
123 }
124
125 private static void createThrowRuntimeExceptionCode(MethodVisitor mv, String msg) {
126 mv.visitTypeInsn(NEW, "java/lang/RuntimeException");
127 mv.visitInsn(DUP);
128 mv.visitLdcInsn(msg);
129 mv.visitMethodInsn(INVOKESPECIAL, "java/lang/RuntimeException", "<init>", "(Ljava/lang/String;)V");
130 mv.visitInsn(ATHROW);
131 }
132
133 private static Class<?> c;
134
135 public static void redefine() throws Exception {
136 RedefineClassHelper.redefineClass(c, loadC(true));
137 }
138
139 public static void main(String[] args) throws ClassNotFoundException, NoSuchMethodException, IllegalAccessException, InvocationTargetException {
140 c = Class.forName("C", true, new RedefineRunningMethodsWithResolutionErrors());
141 c.getMethod("m").invoke(null);
142 }
143 }