|
1
54 package org.logicalcobwebs.cglib.reflect;
55
56 import java.lang.reflect.*;
57 import org.logicalcobwebs.cglib.*;
58 import org.logicalcobwebs.cglib.core.*;
59 import org.logicalcobwebs.asm.ClassVisitor;
60 import org.logicalcobwebs.asm.Type;
61
62
64
145 abstract public class MethodDelegate {
146 private static final MethodDelegateKey KEY_FACTORY =
147 (MethodDelegateKey)KeyFactory.create(MethodDelegateKey.class, KeyFactory.CLASS_BY_NAME);
148
149 protected Object  target;
150 protected String eqMethod;
151
152 interface MethodDelegateKey {
153 Object newInstance(Class delegateClass, String methodName, Class iface);
154 }
155
156 public static MethodDelegate createStatic(Class targetClass, String methodName, Class iface) {
157 Generator gen = new Generator();
158 gen.setTargetClass(targetClass);
159 gen.setMethodName(methodName);
160 gen.setInterface(iface);
161 return gen.create();
162 }
163
164 public static MethodDelegate create(Object target, String methodName, Class iface) {
165 Generator gen = new Generator();
166 gen.setTarget(target);
167 gen.setMethodName(methodName);
168 gen.setInterface(iface);
169 return gen.create();
170 }
171
172 public boolean equals(Object obj) {
173 MethodDelegate other = (MethodDelegate)obj;
174 return target == other.target && eqMethod.equals(other.eqMethod);
175 }
176
177 public int hashCode() {
178 return target.hashCode() ^ eqMethod.hashCode();
179 }
180
181 public Object getTarget() {
182 return target;
183 }
184
185 abstract public MethodDelegate newInstance(Object target);
186
187 public static class Generator extends AbstractClassGenerator {
188 private static final Source SOURCE = new Source(MethodDelegate.class.getName());
189 private static final Signature NEW_INSTANCE =
190 TypeUtils.parseSignature("org.logicalcobwebs.cglib.reflect.MethodDelegate newInstance(Object)");
191 private static final Type METHOD_DELEGATE =
192 TypeUtils.parseType("org.logicalcobwebs.cglib.reflect.MethodDelegate");
193
194 private Object target;
195 private Class targetClass;
196 private String methodName;
197 private Class iface;
198
199 public Generator() {
200 super(SOURCE);
201 }
202
203 public void setTarget(Object target) {
204 this.target = target;
205 this.targetClass = target.getClass();
206 }
207
208 public void setTargetClass(Class targetClass) {
209 this.targetClass = targetClass;
210 }
211
212 public void setMethodName(String methodName) {
213 this.methodName = methodName;
214 }
215
216 public void setInterface(Class iface) {
217 this.iface = iface;
218 }
219
220 protected ClassLoader getDefaultClassLoader() {
221 return targetClass.getClassLoader();
222 }
223
224 public MethodDelegate create() {
225 setNamePrefix(targetClass.getName());
226 Object key = KEY_FACTORY.newInstance(targetClass, methodName, iface);
227 return (MethodDelegate)super.create(key);
228 }
229
230 protected Object firstInstance(Class type) {
231 return ((MethodDelegate)ReflectUtils.newInstance(type)).newInstance(target);
232 }
233
234 protected Object nextInstance(Object instance) {
235 return ((MethodDelegate)instance).newInstance(target);
236 }
237
238 public void generateClass(ClassVisitor v) throws NoSuchMethodException {
239 Method proxy = ReflectUtils.findInterfaceMethod(iface);
240 final Method method = targetClass.getMethod(methodName, proxy.getParameterTypes());
241 if (!proxy.getReturnType().isAssignableFrom(method.getReturnType())) {
242 throw new IllegalArgumentException ("incompatible return types");
243 }
244
245 boolean isStatic = Modifier.isStatic(method.getModifiers());
246 if ((target == null) ^ isStatic) {
247 throw new IllegalArgumentException ("Static method " + (isStatic ? "not " : "") + "expected");
248 }
249
250 ClassEmitter ce = new ClassEmitter(v);
251 CodeEmitter e;
252 ce.begin_class(Constants.ACC_PUBLIC,
253 getClassName(),
254 METHOD_DELEGATE,
255 new Type[]{ Type.getType(iface) },
256 Constants.SOURCE_FILE);
257 ce.declare_field(Constants.PRIVATE_FINAL_STATIC, "eqMethod", Constants.TYPE_STRING, null, null);
258 EmitUtils.null_constructor(ce);
259
260 Method proxied = iface.getDeclaredMethods()[0];
262 e = ce.begin_method(Constants.ACC_PUBLIC,
263 ReflectUtils.getSignature(proxied),
264 ReflectUtils.getExceptionTypes(proxied),
265 null);
266 e.load_this();
267 e.super_getfield("target", Constants.TYPE_OBJECT);
268 e.checkcast(Type.getType(method.getDeclaringClass()));
269 e.load_args();
270 e.invoke(method);
271 e.return_value();
272 e.end_method();
273
274 e = ce.begin_method(Constants.ACC_PUBLIC, NEW_INSTANCE, null, null);
276 e.new_instance_this();
277 e.dup();
278 e.dup2();
279 e.invoke_constructor_this();
280 e.getfield("eqMethod");
281 e.super_putfield("eqMethod", Constants.TYPE_STRING);
282 e.load_arg(0);
283 e.super_putfield("target", Constants.TYPE_OBJECT);
284 e.return_value();
285 e.end_method();
286
287 e = ce.begin_static();
289 Signature sig = ReflectUtils.getSignature(method);
290 e.push(sig.getName() + sig.getDescriptor());
291 e.putfield("eqMethod");
292 e.return_value();
293 e.end_method();
294
295 ce.end_class();
296 }
297 }
298 }
299 |
Popular Tags |
Java API By Example, From Geeks To Geeks.