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package cn.os.du;
import java.lang.reflect.*;
import java.util.ArrayList;
import java.util.Collection;
public class ProxyTest {
public static void main(String[] args) throws Exception
{
Class clazzProxy1=Proxy.getProxyClass(Collection.class.getClassLoader(),Collection.class);
System.out.println(clazzProxy1.getName());
System.out.println("---------------begin constructors list------------");
Constructor[] constructors=clazzProxy1.getConstructors();
for(Constructor constructor:constructors)
{
String name=constructor.getName();
StringBuilder sBuilder=new StringBuilder(name);
sBuilder.append('(');
Class[] clazzParams=constructor.getParameterTypes();
for(Class clazzParam:clazzParams)
{
sBuilder.append(clazzParam.getName()).append(',');
}
if(clazzParams!=null && clazzParams.length!=0)
sBuilder.deleteCharAt(sBuilder.length()-1);
sBuilder.append(')');
System.out.println(sBuilder.toString());
}
System.out.println("---------------begin methods list------------");
Method[] methods=clazzProxy1.getMethods();
for(Method method:methods)
{
String name1=method.getName();
StringBuilder sBuilder1=new StringBuilder(name1);
sBuilder1.append('(');
Class[] clazzParams1=method.getParameterTypes();
for(Class clazzParam:clazzParams1)
{
sBuilder1.append(clazzParam.getName()).append(',');
}
if(clazzParams1!=null && clazzParams1.length!=0)
sBuilder1.deleteCharAt(sBuilder1.length()-1);
sBuilder1.append(')');
System.out.println(sBuilder1.toString());
}
System.out.println("---------------begin create instance object------------");
Constructor constructor=clazzProxy1.getConstructor(InvocationHandler.class);
class MyInvoctionHander1 implements InvocationHandler
{
public Object invoke(Object proxy, Method method, Object[] args)
throws Throwable {
// TODO Auto-generated method stub
return null;
}
}
Collection proxy1=(Collection)constructor.newInstance(new MyInvoctionHander1());
System.out.println(proxy1);
proxy1.clear();
//proxy1.size();
Collection proxy2=(Collection)constructor.newInstance(new InvocationHandler() {
@Override
public Object invoke(Object arg0, Method arg1, Object[] arg2)
throws Throwable {
// TODO Auto-generated method stub
return null;
}
});
//第三个代理对象
Collection proxy3=(Collection)Proxy.newProxyInstance(Collection.class.getClassLoader(),
new Class[]{Collection.class},
new InvocationHandler() {
@Override
public Object invoke(Object arg0, Method arg1, Object[] arg2)
throws Throwable {
ArrayList target=new ArrayList();
long beginTime=System.currentTimeMillis();
Object retVal=method.invoke(target,args);//这一行什么意思，不太懂
long endTime=System.currentTimeMillis();
System.out.println(method.getName()+"run time of"+(endTime-beginTime));
return retVal;
}
});
proxy3.add("xxxx");
proxy3.add("sdf");
proxy3.add("sffgf");
System.out.println(proxy3.size());
}
}

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