//: net/mindview/util/TwoTuple.javapackage net.mindview.util;public class TwoTuple<A,B> { public final A first; public final B second; public TwoTuple(A a, B b) { first = a; second = b; } public String toString() {return "(" + first + ", " + second + ")"; }} ///:~
package Lesson15_generices;//: generics/Mixins.javaimport java.util.*;interface TimeStamped { long getStamp(); }class TimeStampedImp implements TimeStamped { private final long timeStamp; public TimeStampedImp() {timeStamp = new Date().getTime(); } public long getStamp() { return timeStamp; }}interface SerialNumbered { long getSerialNumber(); }class SerialNumberedImp implements SerialNumbered { private static long counter = 1; private final long serialNumber = counter++; public long getSerialNumber() { return serialNumber; }}interface Basic { public void set(String val); public String get();}class BasicImp implements Basic { private String value; public void set(String val) { value = val; } public String get() { return value; }}class Mixin extends BasicImpimplements TimeStamped, SerialNumbered { private TimeStamped timeStamp = new TimeStampedImp(); private SerialNumbered serialNumber =new SerialNumberedImp(); public long getStamp() { return timeStamp.getStamp(); } public long getSerialNumber() {return serialNumber.getSerialNumber(); }}public class Mixins { public static void main(String[] args) {Mixin mixin1 = new Mixin(), mixin2 = new Mixin();mixin1.set("test string 1");mixin2.set("test string 2");System.out.println(mixin1.get() + " " +mixin1.getStamp() + " " + mixin1.getSerialNumber());System.out.println(mixin2.get() + " " +mixin2.getStamp() + " " + mixin2.getSerialNumber()); }} /* Output: (Sample)test string 1 1132437151359 1test string 2 1132437151359 2*///:~
/*** 书本:《Thinking In Java》* 功能:与动态代理混合* 文件:DynamicProxyMixin.java* 时间:2015年4月21日10:38:44* 作者:cutter_point*/package Lesson15_generices;import java.lang.reflect.InvocationHandler;import java.lang.reflect.Method;import java.lang.reflect.Proxy;import java.util.HashMap;import java.util.Map;import net.mindview.util.TwoTuple;import static net.mindview.util.Tuple.*;class MixinProxy implements InvocationHandler{Map<String, Object> delegetesByMethod;public MixinProxy(TwoTuple<Object, Class<?>>… pairs)//这句表示，多个TwoTuple<Object, Class<?>>类型的参数{delegetesByMethod = new HashMap<String, Object>();for(TwoTuple<Object, Class<?>> pair : pairs){for(Method method : pair.second.getMethods())//取得这个类的所有方法,遍历{String methodName = method.getName();if(!delegetesByMethod.containsKey(methodName))//如果这个map包含这个指定键就返回truedelegetesByMethod.put(methodName, pair.first);//吧有这个方法的类放进去和这个方法形成映射}}}@Overridepublic Object invoke(Object proxy, Method method, Object[] args)throws Throwable{String methodName = method.getName();//取得方法的名字Object delegate = delegetesByMethod.get(methodName);//根据方法名取得对应的方法System.out.println("动态代理里面的invoke方法");return method.invoke(delegate, args);//回调}public static Object newInstance(TwoTuple… pairs){Class interfaces[] = new Class[pairs.length];//创建长度为pairs.length的Class数组for(int i = 0; i < pairs.length; ++i){interfaces[i] = (Class)pairs[i].second;//取得所有的类的方法,初始化这个数组，里面存放的是第二个参数，这里应该是类型信息}//取得c1的类加载器，让代理类实现的时候使用同一个类加载器ClassLoader cl = pairs[0].first.getClass().getClassLoader();//返回一个指定接口的代理类实例，，该接口可以将方法调用指派到指定的调用处理程序。/** * c1是代理对象使用的加载类，interfaces是代理类要实现的接口列表，第三个参数new MixinProxy(pairs)是指派方法调用的调用处理程序*/return Proxy.newProxyInstance(cl, interfaces, new MixinProxy(pairs));}}public class DynamicProxyMixin{public static void main(String[] args){Object mixin = MixinProxy.newInstance(tuple(new BasicImp(), Basic.class),tuple(new TimeStampedImp(), TimeStamped.class),tuple(new SerialNumberedImp(),SerialNumbered.class));Basic b = (Basic)mixin;TimeStamped t = (TimeStamped)mixin;SerialNumbered s = (SerialNumbered)mixin;b.set("cutter_point");//调用set方法的时候，代理拦截，在实现之前执行代理System.out.println(b.get());//调用get方法了，再次触发System.out.println(t.getStamp());//同上System.out.println(s.getSerialNumber());//同上}}输出：
动态代理里面的invoke方法动态代理里面的invoke方法cutter_point动态代理里面的invoke方法1431995142154动态代理里面的invoke方法1
冬天已经到来，春天还会远吗?
