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1
54 package org.logicalcobwebs.cglib.reflect;
55
56 import java.lang.reflect.*;
57 import org.logicalcobwebs.cglib.core.*;
58 import org.logicalcobwebs.asm.ClassVisitor;
59 import org.logicalcobwebs.asm.Type;
60
61
65 abstract public class ConstructorDelegate {
66 private static final ConstructorKey KEY_FACTORY =
67 (ConstructorKey)KeyFactory.create(ConstructorKey.class, KeyFactory.CLASS_BY_NAME);
68
69 interface ConstructorKey {
70 public Object  newInstance(Class declaring, Class iface);
71 }
72
73 protected ConstructorDelegate() {
74 }
75
76 public static ConstructorDelegate create(Class targetClass, Class iface) {
77 Generator gen = new Generator();
78 gen.setTargetClass(targetClass);
79 gen.setInterface(iface);
80 return gen.create();
81 }
82
83 public static class Generator extends AbstractClassGenerator {
84 private static final Source SOURCE = new Source(ConstructorDelegate.class.getName());
85 private static final Type CONSTRUCTOR_DELEGATE =
86 TypeUtils.parseType("org.logicalcobwebs.cglib.reflect.ConstructorDelegate");
87
88 private Class iface;
89 private Class targetClass;
90
91 public Generator() {
92 super(SOURCE);
93 }
94
95 public void setInterface(Class iface) {
96 this.iface = iface;
97 }
98
99 public void setTargetClass(Class targetClass) {
100 this.targetClass = targetClass;
101 }
102
103 public ConstructorDelegate create() {
104 setNamePrefix(targetClass.getName());
105 Object key = KEY_FACTORY.newInstance(iface, targetClass);
106 return (ConstructorDelegate)super.create(key);
107 }
108
109 protected ClassLoader getDefaultClassLoader() {
110 return targetClass.getClassLoader();
111 }
112
113 public void generateClass(ClassVisitor v) {
114 setNamePrefix(targetClass.getName());
115
116 final Method newInstance = ReflectUtils.findNewInstance(iface);
117 if (!newInstance.getReturnType().isAssignableFrom(targetClass)) {
118 throw new IllegalArgumentException ("incompatible return type");
119 }
120 final Constructor constructor;
121 try {
122 constructor = targetClass.getDeclaredConstructor(newInstance.getParameterTypes());
123 } catch (NoSuchMethodException e) {
124 throw new IllegalArgumentException ("interface does not match any known constructor");
125 }
126
127 ClassEmitter ce = new ClassEmitter(v);
128 ce.begin_class(Constants.ACC_PUBLIC,
129 getClassName(),
130 CONSTRUCTOR_DELEGATE,
131 new Type[]{ Type.getType(iface) },
132 Constants.SOURCE_FILE);
133 Type declaring = Type.getType(constructor.getDeclaringClass());
134 EmitUtils.null_constructor(ce);
135 CodeEmitter e = ce.begin_method(Constants.ACC_PUBLIC,
136 ReflectUtils.getSignature(newInstance),
137 ReflectUtils.getExceptionTypes(newInstance),
138 null);
139 e.new_instance(declaring);
140 e.dup();
141 e.load_args();
142 e.invoke_constructor(declaring, ReflectUtils.getSignature(constructor));
143 e.return_value();
144 e.end_method();
145 ce.end_class();
146 }
147
148 protected Object firstInstance(Class type) {
149 return ReflectUtils.newInstance(type);
150 }
151
152 protected Object nextInstance(Object instance) {
153 return instance;
154 }
155 }
156 }
157 |
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