深入理解Java Proxy：
http://blog.csdn.net/rokii/article/details/4046098
整理之后的代码：
package com.stono.reftest;
import java.lang.reflect.Constructor;
import java.lang.reflect.Field;
import java.lang.reflect.InvocationHandler;
import java.lang.reflect.Method;
import java.lang.reflect.Modifier;
import java.lang.reflect.Proxy;
interface BusinessProcessor {
void processBusiness();
void processBusiness2(); // 这样$Proxy0会有 Method m4属性；
}
class BusinessProcessorImpl implements BusinessProcessor {
@Override
public void processBusiness() {
System.out.println("processing business...");
}
@Override
public void processBusiness2() {
System.out.println("processing business 2...");
}
}
class BusinessProcessorHandler implements InvocationHandler {
private Object target = null;
public BusinessProcessorHandler(Object target) {
this.target = target;
}
@Override
public Object invoke(Object proxy, Method method, Object[] args) throws Throwable {
System.out.println("You can do something before your business");
Object result = method.invoke(target, args);
System.out.println("You can do something after your business");
return result;
}
}
public class DynProxy {
public static void main(String[] args) {
BusinessProcessorImpl bpimpl = new BusinessProcessorImpl();
BusinessProcessorHandler handler = new BusinessProcessorHandler(bpimpl);
BusinessProcessor bp = (BusinessProcessor) Proxy.newProxyInstance(bpimpl.getClass().getClassLoader(), bpimpl.getClass().getInterfaces(), handler);
bp.processBusiness();
bp.processBusiness2();
System.out.println(bp.getClass().getName());
Class clz = bp.getClass();
printClassDefinition(clz);
}
public static String getModifier(int modifier) {
String result = "";
switch (modifier) {
case Modifier.PRIVATE:
result = "private";
case Modifier.PUBLIC:
result = "public";
case Modifier.PROTECTED:
result = "protected";
case Modifier.ABSTRACT:
result = "abstract";
case Modifier.FINAL:
result = "final";
case Modifier.NATIVE:
result = "native";
case Modifier.STATIC:
result = "static";
case Modifier.SYNCHRONIZED:
result = "synchronized";
case Modifier.STRICT:
result = "strict";
case Modifier.TRANSIENT:
result = "transient";
case Modifier.VOLATILE:
result = "volatile";
case Modifier.INTERFACE:
result = "interface";
}
return result;
}
public static void printClassDefinition(Class clz) {
String clzModifier = getModifier(clz.getModifiers());
if (clzModifier != null && !clzModifier.equals("")) {
clzModifier = clzModifier + " ";
}
String superClz = clz.getSuperclass().getName();
if (superClz != null && !superClz.equals("")) {
superClz = "extends " + superClz;
}
Class[] interfaces = clz.getInterfaces();
String inters = "";
for (int i = 0; i < interfaces.length; i++) {
if (i == 0) {
inters += "implements ";
}
inters += interfaces[i].getName();
}
System.out.println(clzModifier + clz.getName() + " " + superClz + " " + inters);
System.out.println("{");
Constructor<?>[] constructors = clz.getConstructors();// 长度为1
for (int i = 0; i < constructors.length; i++) {
Constructor<?> constructor = constructors[i];
String modifier = getModifier(constructor.getModifiers());
if (modifier != null && !modifier.equals("")) {
modifier = modifier + " ";
}
String name = constructor.getName();
Class<?>[] parameterTypes = constructor.getParameterTypes();
String params = "";
for (int j = 0; j < parameterTypes.length; j++) {
params += parameterTypes[i].getName() + ", ";
}
String substring = params.substring(0, params.length() - 2);
System.out.println(" " + modifier + name + "(" + substring + ");");
}
System.out.println();
Field[] fields = clz.getDeclaredFields();
for (int i = 0; i < fields.length; i++) {
String modifier = getModifier(fields[i].getModifiers());
if (modifier != null && !modifier.equals("")) {
modifier = modifier + " ";
}
String fieldName = fields[i].getName();
String fieldType = fields[i].getType().getName();
System.out.println(" " + modifier + fieldType + " " + fieldName + ";");
}
System.out.println();
Method[] methods = clz.getDeclaredMethods();
for (int i = 0; i < methods.length; i++) {
Method method = methods[i];
String modifier = getModifier(method.getModifiers());
if (modifier != null && !modifier.equals("")) {
modifier = modifier + " ";
}
String methodName = method.getName();
Class returnClz = method.getReturnType();
String retrunType = returnClz.getName();
Class[] clzs = method.getParameterTypes();
String paraList = "(";
for (int j = 0; j < clzs.length; j++) {
paraList += clzs[j].getName();
if (j != clzs.length - 1) {
paraList += ", ";
}
}
paraList += ")";
clzs = method.getExceptionTypes();
String exceptions = "";
for (int j = 0; j < clzs.length; j++) {
if (j == 0) {
exceptions += "throws ";
}
exceptions += clzs[j].getName();
if (j != clzs.length - 1) {
exceptions += ", ";
}
}
exceptions += ";";
String methodPrototype = modifier + retrunType + " " + methodName + paraList + exceptions;
System.out.println(" " + methodPrototype);
}
System.out.println("}");
}
}