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1
30 package org.objectweb.asm;
31
32 import java.lang.instrument.ClassFileTransformer  ;
33 import java.lang.instrument.IllegalClassFormatException ;
34 import java.lang.instrument.Instrumentation ;
35 import java.security.ProtectionDomain ;
36 import java.util.HashSet ;
37
38 import org.objectweb.asm.attrs.CodeComment;
39
40 import junit.framework.TestSuite;
41
42 public class ClassWriterResizeInsnsTest extends AbstractTest {
43
44 public static void premain(
45 final String agentArgs,
46 final Instrumentation inst)
47 {
48 inst.addTransformer(new ClassFileTransformer () {
49 public byte[] transform(
50 final ClassLoader loader,
51 final String className,
52 final Class classBeingRedefined,
53 final ProtectionDomain domain,
54 byte[] b) throws IllegalClassFormatException
55 {
56 String n = className.replace('/', '.');
57 if (agentArgs.length() == 0 || n.indexOf(agentArgs) != -1) {
58 try {
59 b = transformClass(b, ClassWriter.COMPUTE_FRAMES);
60 if (n.equals("pkg.FrameMap")) {
61 transformClass(b, 0);
62 }
63 return b;
64 } catch (Throwable e) {
65 return transformClass(b, 0);
66 }
67 } else {
68 return null;
69 }
70 }
71 });
72 }
73
74 private static byte[] transformClass(final byte[] clazz, final int flags) {
75 ClassReader cr = new ClassReader(clazz);
76 ClassWriter cw = new ClassWriter(flags) {
77 protected String getCommonSuperClass(
78 final String type1,
79 final String type2)
80 {
81 ClassInfo c, d;
82 try {
83 c = new ClassInfo(type1, getClass().getClassLoader());
84 d = new ClassInfo(type2, getClass().getClassLoader());
85 } catch (Throwable e) {
86 throw new RuntimeException (e);
87 }
88 if (c.isAssignableFrom(d)) {
89 return type1;
90 }
91 if (d.isAssignableFrom(c)) {
92 return type2;
93 }
94 if (c.isInterface() || d.isInterface()) {
95 return "java/lang/Object";
96 } else {
97 do {
98 c = c.getSuperclass();
99 } while (!c.isAssignableFrom(d));
100 return c.getType().getInternalName();
101 }
102 }
103 };
104 ClassAdapter ca = new ClassAdapter(cw) {
105
106 private boolean transformed = false;
107
108 public void visit(
109 int version,
110 int access,
111 String name,
112 String signature,
113 String superName,
114 String [] interfaces)
115 {
116 if (flags == ClassWriter.COMPUTE_FRAMES) {
117 version = Opcodes.V1_6;
118 }
119 super.visit(version,
120 access,
121 name,
122 signature,
123 superName,
124 interfaces);
125 }
126
127 public MethodVisitor visitMethod(
128 final int access,
129 final String name,
130 final String desc,
131 final String signature,
132 final String [] exceptions)
133 {
134 return new MethodAdapter(cv.visitMethod(access,
135 name,
136 desc,
137 signature,
138 exceptions))
139 {
140 private HashSet labels = new HashSet ();
141
142 public void visitLabel(final Label label) {
143 super.visitLabel(label);
144 labels.add(label);
145 }
146
147 public void visitJumpInsn(
148 final int opcode,
149 final Label label)
150 {
151 super.visitJumpInsn(opcode, label);
152 if (opcode != Opcodes.GOTO) {
153 if (!transformed && !labels.contains(label)) {
154 transformed = true;
155 for (int i = 0; i < 33000; ++i) {
156 mv.visitInsn(Opcodes.NOP);
157 }
158 }
159 }
160 }
161 };
162 }
163 };
164 cr.accept(ca, new Attribute[] { new CodeComment() }, 0);
165 return cw.toByteArray();
166 }
167
168 public static TestSuite suite() throws Exception {
169 return new ClassWriterResizeInsnsTest().getSuite();
170 }
171
172 public void test() throws Exception {
173 try {
174 Class.forName(n, true, getClass().getClassLoader());
175 } catch (NoClassDefFoundError ncdfe) {
176 } catch (UnsatisfiedLinkError ule) {
178 } catch (ClassFormatError cfe) {
180 fail(cfe.getMessage());
181 } catch (VerifyError ve) {
182 fail(ve.toString());
183 }
184 }
185 }
186 |
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