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16 package net.sf.cglib.transform.impl;
17
18 import net.sf.cglib.transform.*;
19 import java.lang.reflect.*;
20 import java.util.*;
21 import net.sf.cglib.core.*;
22 import org.objectweb.asm.Attribute;
23 import org.objectweb.asm.Type;
24
25
28 public class AddDelegateTransformer extends ClassEmitterTransformer {
29 private static final String  DELEGATE = "$CGLIB_DELEGATE";
30 private static final Signature CSTRUCT_OBJECT =
31 TypeUtils.parseSignature("void <init>(Object)");
32
33 private Class [] delegateIf;
34 private Class delegateImpl;
35 private Type delegateType;
36
37
38 public AddDelegateTransformer(Class delegateIf[], Class delegateImpl) {
39 try {
40 delegateImpl.getConstructor(new Class []{ Object .class });
41 this.delegateIf = delegateIf;
42 this.delegateImpl = delegateImpl;
43 delegateType = Type.getType(delegateImpl);
44 } catch (NoSuchMethodException e) {
45 throw new CodeGenerationException(e);
46 }
47 }
48
49 public void begin_class(int version, int access, String className, Type superType, Type[] interfaces, String sourceFile) {
50
51 if(!TypeUtils.isInterface(access)){
52
53 Type[] all = TypeUtils.add(interfaces, TypeUtils.getTypes(delegateIf));
54 super.begin_class(version, access, className, superType, all, sourceFile);
55
56 declare_field(Constants.ACC_PRIVATE | Constants.ACC_TRANSIENT,
57 DELEGATE,
58 delegateType,
59 null);
60 for (int i = 0; i < delegateIf.length; i++) {
61 Method[] methods = delegateIf[i].getMethods();
62 for (int j = 0; j < methods.length; j++) {
63 if (Modifier.isAbstract(methods[j].getModifiers())) {
64 addDelegate(methods[j]);
65 }
66 }
67 }
68 }else{
69 super.begin_class(version, access, className, superType, interfaces, sourceFile);
70 }
71 }
72
73 public CodeEmitter begin_method(int access, Signature sig, Type[] exceptions) {
74 final CodeEmitter e = super.begin_method(access, sig, exceptions);
75 if (sig.getName().equals(Constants.CONSTRUCTOR_NAME)) {
76 return new CodeEmitter(e) {
77 private boolean transformInit = true;
78 public void visitMethodInsn(int opcode, String owner, String name, String desc) {
79 super.visitMethodInsn(opcode, owner, name, desc);
80 if (transformInit && opcode == Constants.INVOKESPECIAL) {
81 load_this();
82 new_instance(delegateType);
83 dup();
84 load_this();
85 invoke_constructor(delegateType, CSTRUCT_OBJECT);
86 putfield(DELEGATE);
87 transformInit = false;
88 }
89 }
90 };
91 }
92 return e;
93 }
94
95 private void addDelegate(Method m) {
96 Method delegate;
97 try {
98 delegate = delegateImpl.getMethod(m.getName(), m.getParameterTypes());
99 if (!delegate.getReturnType().getName().equals(m.getReturnType().getName())){
100 throw new IllegalArgumentException ("Invalid delegate signature " + delegate);
101 }
102 } catch (NoSuchMethodException e) {
103 throw new CodeGenerationException(e);
104 }
105
106 final Signature sig = ReflectUtils.getSignature(m);
107 Type[] exceptions = TypeUtils.getTypes(m.getExceptionTypes());
108 CodeEmitter e = super.begin_method(Constants.ACC_PUBLIC, sig, exceptions);
109 e.load_this();
110 e.getfield(DELEGATE);
111 e.load_args();
112 e.invoke_virtual(delegateType, sig);
113 e.return_value();
114 e.end_method();
115 }
116 }
117
118
119
120 |
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