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54 package org.logicalcobwebs.cglib.proxy;
55
56 import java.lang.reflect.*;
57 import java.util.*;
58 import org.logicalcobwebs.cglib.core.*;
59 import org.logicalcobwebs.asm.Label;
60 import org.logicalcobwebs.asm.Type;
61
62 class MethodInterceptorGenerator
63 implements CallbackGenerator
64 {
65 public static final MethodInterceptorGenerator INSTANCE = new MethodInterceptorGenerator();
66
67 static final String  FIND_PROXY_NAME = "CGLIB$findMethodProxy";
68 static final Class [] FIND_PROXY_TYPES = { Signature.class };
69
70 private static final Signature FIND_PROXY =
71 new Signature(FIND_PROXY_NAME,
72 TypeUtils.parseType("org.logicalcobwebs.cglib.proxy.MethodProxy"),
73 TypeUtils.getTypes(FIND_PROXY_TYPES));
74
75 private static final Type ABSTRACT_METHOD_ERROR =
76 TypeUtils.parseType("AbstractMethodError");
77 private static final Type METHOD =
78 TypeUtils.parseType("java.lang.reflect.Method");
79 private static final Type METHOD_PROXY =
80 TypeUtils.parseType("org.logicalcobwebs.cglib.proxy.MethodProxy");
81 private static final Type METHOD_INTERCEPTOR =
82 TypeUtils.parseType("org.logicalcobwebs.cglib.proxy.MethodInterceptor");
83 private static final Signature GET_DECLARING_CLASS =
84 TypeUtils.parseSignature("Class getDeclaringClass()");
85 private static final Signature GET_CLASS_LOADER =
86 TypeUtils.parseSignature("ClassLoader getClassLoader()");
87 private static final Signature MAKE_PROXY =
88 TypeUtils.parseSignature("org.logicalcobwebs.cglib.proxy.MethodProxy create(ClassLoader, Class, Class, String, String, String)");
89 private static final Signature INTERCEPT =
90 TypeUtils.parseSignature("Object intercept(Object, java.lang.reflect.Method, Object[], org.logicalcobwebs.cglib.proxy.MethodProxy)");
91 private static final Signature TO_STRING =
92 TypeUtils.parseSignature("String toString()");
93
94 public void generate(ClassEmitter ce, Context context) {
95 Map sigMap = new HashMap();
96 for (Iterator it = context.getMethods(); it.hasNext();) {
97 Method method = (Method)it.next();
98 String accessName = getAccessName(context, method);
99 String fieldName = getFieldName(context, method);
100 sigMap.put(ReflectUtils.getSignature(method).toString(), accessName);
101
102 ce.declare_field(Constants.PRIVATE_FINAL_STATIC, fieldName, METHOD, null, null);
103 ce.declare_field(Constants.PRIVATE_FINAL_STATIC, accessName, METHOD_PROXY, null, null);
104 CodeEmitter e;
105
106 e = ce.begin_method(Constants.ACC_FINAL,
108 new Signature(getAccessName(context, method),
109 ReflectUtils.getSignature(method).getDescriptor()),
110 ReflectUtils.getExceptionTypes(method),
111 null);
112 if (Modifier.isAbstract(method.getModifiers())) {
113 e.throw_exception(ABSTRACT_METHOD_ERROR, method.toString() + " is abstract" );
114 } else {
115 e.load_this();
116 e.load_args();
117 e.super_invoke(ReflectUtils.getSignature(method));
118 }
119 e.return_value();
120 e.end_method();
121
122 e = ce.begin_method(context.getModifiers(method),
124 ReflectUtils.getSignature(method),
125 ReflectUtils.getExceptionTypes(method),
126 null);
127 Label nullInterceptor = e.make_label();
128 context.emitCallback(e, context.getIndex(method));
129 e.dup();
130 e.ifnull(nullInterceptor);
131
132 e.load_this();
133 e.getfield(fieldName);
134 e.create_arg_array();
135 e.getfield(accessName);
136 e.invoke_interface(METHOD_INTERCEPTOR, INTERCEPT);
137 e.unbox_or_zero(Type.getType(method.getReturnType()));
138 e.return_value();
139
140 e.mark(nullInterceptor);
141 e.load_this();
142 e.load_args();
143 e.super_invoke(ReflectUtils.getSignature(method));
144 e.return_value();
145 e.end_method();
146 }
147 generateFindProxy(ce, sigMap);
148 }
149
150 private String getFieldName(Context context, Method method) {
151 return "CGLIB$$METHOD_" + context.getUniqueName(method);
152 }
153
154 private String getAccessName(Context context, Method method) {
155 return "CGLIB$$ACCESS_" + context.getUniqueName(method);
156 }
157
158 public void generateStatic(CodeEmitter e, final Context context) {
159
168
169 Local thisclass = e.make_local();
170 EmitUtils.load_class_this(e);
171 e.dup();
172 e.store_local(thisclass);
173 e.invoke_virtual(Constants.TYPE_CLASS, GET_CLASS_LOADER);
174
175 for (Iterator it = context.getMethods(); it.hasNext();) {
176 e.dup();
177 Method method = (Method)it.next();
178 EmitUtils.load_method(e, method);
179 e.dup();
180 e.putfield(getFieldName(context, method));
181
182 String accessName = getAccessName(context, method);
183 Signature sig = ReflectUtils.getSignature(method);
184 e.invoke_virtual(METHOD, GET_DECLARING_CLASS);
185 e.load_local(thisclass);
186 e.push(sig.getDescriptor());
187 e.push(sig.getName());
188 e.push(accessName);
189 e.invoke_static(METHOD_PROXY, MAKE_PROXY);
190 e.putfield(accessName);
191 }
192 }
193
194 public void generateFindProxy(ClassEmitter ce, final Map sigMap) {
195 final CodeEmitter e = ce.begin_method(Constants.ACC_PUBLIC | Constants.ACC_STATIC,
196 FIND_PROXY,
197 null,
198 null);
199 e.load_arg(0);
200 e.invoke_virtual(Constants.TYPE_OBJECT, TO_STRING);
201 ObjectSwitchCallback callback = new ObjectSwitchCallback() {
202 public void processCase(Object key, Label end) {
203 e.getfield((String )sigMap.get(key));
204 e.return_value();
205 }
206 public void processDefault() {
207 e.aconst_null();
208 e.return_value();
209 }
210 };
211 EmitUtils.string_switch(e,
212 (String [])sigMap.keySet().toArray(new String [0]),
213 Constants.SWITCH_STYLE_HASH,
214 callback);
215 e.end_method();
216 }
217 }
218 |
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