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1
46 package org.codehaus.groovy.classgen;
47
48 import groovy.lang.MetaMethod;
49
50 import java.util.List  ;
51
52 import org.objectweb.asm.ClassVisitor;
53 import org.objectweb.asm.CodeVisitor;
54 import org.objectweb.asm.Constants;
55 import org.objectweb.asm.Label;
56
57
63 public class ReflectorGenerator implements Constants {
64
65 private List methods;
66 private ClassVisitor cw;
67 private CodeVisitor cv;
68 private BytecodeHelper helper = new BytecodeHelper(null);
69 private String classInternalName;
70
71 public ReflectorGenerator(List methods) {
72 this.methods = methods;
73 }
74
75 public void generate(ClassVisitor cw, String className) {
76 this.cw = cw;
77 String fileName = className;
78 int idx = className.lastIndexOf('.');
79 if (idx > 0) {
80 fileName = className.substring(idx + 1);
81 }
82 fileName += ".java";
83
84 classInternalName = BytecodeHelper.getClassInternalName(className);
85 cw.visit(ClassGenerator.asmJDKVersion, ACC_PUBLIC + ACC_SUPER, classInternalName, "org/codehaus/groovy/runtime/Reflector", null, fileName);
86
87 cv = cw.visitMethod(ACC_PUBLIC, "<init>", "()V", null, null);
88 cv.visitVarInsn(ALOAD, 0);
89 cv.visitMethodInsn(INVOKESPECIAL, "org/codehaus/groovy/runtime/Reflector", "<init>", "()V");
90 cv.visitInsn(RETURN);
91 cv.visitMaxs(1, 1);
92
93 generateInvokeMethod();
94
95 cw.visitEnd();
96 }
97
98 protected void generateInvokeMethod() {
99 int methodCount = methods.size();
100
101 cv =
102 cw.visitMethod(
103 ACC_PUBLIC,
104 "invoke",
105 "(Lgroovy/lang/MetaMethod;Ljava/lang/Object;[Ljava/lang/Object;)Ljava/lang/Object;",
106 null,
107 null);
108 helper = new BytecodeHelper(cv);
109
110 cv.visitVarInsn(ALOAD, 1);
111 cv.visitMethodInsn(INVOKEVIRTUAL, "groovy/lang/MetaMethod", "getMethodIndex", "()I");
112 Label defaultLabel = new Label();
113 Label[] labels = new Label[methodCount];
114 int[] indices = new int[methodCount];
115 for (int i = 0; i < methodCount; i++) {
116 labels[i] = new Label();
117
118 MetaMethod method = (MetaMethod) methods.get(i);
119 method.setMethodIndex(i + 1);
120 indices[i] = method.getMethodIndex();
121
122 }
124
125 cv.visitLookupSwitchInsn(defaultLabel, indices, labels);
126
128 for (int i = 0; i < methodCount; i++) {
129 cv.visitLabel(labels[i]);
130
131 MetaMethod method = (MetaMethod) methods.get(i);
132 invokeMethod(method);
133 if (method.getReturnType() == void.class) {
134 cv.visitInsn(ACONST_NULL);
135 }
136 cv.visitInsn(ARETURN);
137 }
138
139 cv.visitLabel(defaultLabel);
140 cv.visitVarInsn(ALOAD, 0);
141 cv.visitVarInsn(ALOAD, 1);
142 cv.visitVarInsn(ALOAD, 2);
143 cv.visitVarInsn(ALOAD, 3);
144 cv.visitMethodInsn(
145 INVOKEVIRTUAL,
146 classInternalName,
147 "noSuchMethod",
148 "(Lgroovy/lang/MetaMethod;Ljava/lang/Object;[Ljava/lang/Object;)Ljava/lang/Object;");
149 cv.visitInsn(ARETURN);
150 cv.visitMaxs(4, 4);
151 }
152
153 protected void invokeMethod(MetaMethod method) {
154
158 Class ownerClass = method.getInterfaceClass();
159 boolean useInterface = false;
160 if (ownerClass == null) {
161 ownerClass = method.getDeclaringClass();
162 }
163 else {
164 useInterface = true;
165 }
166 String type = BytecodeHelper.getClassInternalName(ownerClass.getName());
167 String descriptor = BytecodeHelper.getMethodDescriptor(method.getReturnType(), method.getParameterTypes());
168
169
172 if (method.isStatic()) {
173 loadParameters(method, 3);
174 cv.visitMethodInsn(INVOKESTATIC, type, method.getName(), descriptor);
175 }
176 else {
177 cv.visitVarInsn(ALOAD, 2);
178 helper.doCast(ownerClass);
179 loadParameters(method, 3);
180 cv.visitMethodInsn((useInterface) ? INVOKEINTERFACE : INVOKEVIRTUAL, type, method.getName(), descriptor);
181 }
182
183 helper.box(method.getReturnType());
184 }
185
186
271
272 protected void loadParameters(MetaMethod method, int argumentIndex) {
273 Class [] parameters = method.getParameterTypes();
274 int size = parameters.length;
275 for (int i = 0; i < size; i++) {
276 cv.visitVarInsn(ALOAD, argumentIndex);
277 helper.pushConstant(i);
278 cv.visitInsn(AALOAD);
279
280 Class type = parameters[i];
282 if (type.isPrimitive()) {
283 helper.unbox(type);
284 }
285 else {
286 helper.doCast(type.getName());
287 }
288 }
289 }
290 }
291 |
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