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1 package org.hansel;
2
3 import org.objectweb.asm.ClassAdapter;
4 import org.objectweb.asm.ClassVisitor;
5 import org.objectweb.asm.MethodVisitor;
6 import org.objectweb.asm.Opcodes;
7 import org.objectweb.asm.tree.ClassNode;
8 import org.objectweb.asm.tree.InsnList;
9 import org.objectweb.asm.tree.MethodNode;
10 import org.objectweb.asm.tree.analysis.Analyzer;
11 import org.objectweb.asm.tree.analysis.AnalyzerException;
12 import org.objectweb.asm.tree.analysis.Frame;
13
14 public class TransformingAdapter extends ClassAdapter {
15 private ClassNode classNode;
16 private ClassLoader  loader;
17
18 public TransformingAdapter(final ClassVisitor cv, final ClassNode classNode,
19 ClassLoader loader) {
20 super(cv);
21 this.classNode = classNode;
22 this.loader = loader;
23 }
24
25 public void visit(int version, int access, String name, String signature, String superName, String [] interfaces) {
26 super.visit(version, access, name, signature, superName, interfaces);
27 }
28
29 private MethodNode getMethodNode(String name, String desc) {
30 for (int i=0; i<classNode.methods.size(); i++) {
31 MethodNode mn = (MethodNode) classNode.methods.get(i);
32 if (mn.name.equals(name) && mn.desc.equals(desc)) {
33 return mn;
34 }
35 }
36
37 throw new IllegalStateException ("Method: " + name + " - " + desc
38 + " not found.");
39 }
40
41 public MethodVisitor visitMethod(int access, String name, String desc, String signature, String [] exceptions) {
42 try {
44 MethodNode mn = getMethodNode(name, desc);
45 if ((mn.access & Opcodes.ACC_ABSTRACT) != 0) {
46 return cv.visitMethod(access, name, desc, signature,
47 exceptions);
48 }
49
50 if (isPrivateEmptyConstructor(name, access, mn.instructions)
51 || isSynthetic(access)) {
52 return super.visitMethod(access, name, desc, signature, exceptions);
53 }
54
55 Analyzer analyzer =
56 new Analyzer(new HanselInterpreter(mn.localVariables)) {
57 protected Frame newFrame (final int nLocals, final int nStack) {
58 return new HanselFrame(nLocals, nStack);
59 }
60
61 protected Frame newFrame (final Frame src) {
62 return new HanselFrame((HanselFrame) src);
63 }
64 };
65
66 Frame[] frames = analyzer.analyze(classNode.name, mn);
67 HanselFrame[] hanselFrames = new HanselFrame[frames.length];
68 for (int i=0; i<frames.length; i++) {
69 hanselFrames[i] = (HanselFrame) frames[i];
70 }
71 return new HanselCodeAdapter(access, classNode.name, mn.name,
72 mn.instructions, mn.tryCatchBlocks,
73 cv.visitMethod(access, name, desc, signature,
74 exceptions),
75 hanselFrames, loader);
76 } catch (AnalyzerException e) {
77 e.printStackTrace();
78 throw new IllegalStateException (classNode.name + "." + name, e);
79 }
80 }
81
82 private boolean isSynthetic(int access) {
83 return (access & Opcodes.ACC_SYNTHETIC) != 0;
84 }
85
86 private boolean isPrivateEmptyConstructor(String name,
87 int access, InsnList instructions) {
88 return ((access & Opcodes.ACC_PRIVATE) != 0)
89 && "<init>".equals(name) && (instructions.size() == 6);
90 }
91 }
92 |
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