浅谈静态代理和动态代理

public class CustomerLoginAction implements LoginAction {
//执行验证操作
public void execute() throws SQLException, LoginException  {
}
}

import java.sql.SQLException;

public interface  LoginAction  {

public void execute()throws SQLException, LoginException;

}

public class ProxyCustomerLoginAction implements LoginAction {

private LoginAction  customerLogin ;

public ProxyCustomerLoginAction(LoginAction customerLogin){
this.customerLogin = customerLogin;
}
public void execute() throws SQLException, LoginException{
System.out.println("begin the login validate");
customerLogin.execute();
System.out.println("end the login validate");
}

}

public static void main(String[] args) {
CustomerLoginAction customerLoginAction = new CustomerLoginAction();
LoginAction pAction = new ProxyCustomerLoginAction(customerLoginAction);
}

public class DynaProxyCustomerLoginHandler implements InvocationHandler {

private Object realclass;

public Object binding(Object realclass) {
this.realclass = realclass;
//返回一个代理类的实例
return Proxy.newProxyInstance(realclass.getClass().getClassLoader(),
realclass.getClass().getInterfaces(), this);
}

//在被代理类的实例前后增加功能
public Object invoke(Object proxy, Method method, Object[] args)
throws Throwable {
Object obj = null;
//如果被代理类方法的名字包含指定的字符串"execute"，则在被代理类方法执行的前后增加新的功能，
//否则直接执行被代理类的方法，而不增加新的功能。
if (method.getName().contains("execute")) {
System.out.println("begin the login validate");
try {
//执行被代理类的方法
obj = method.invoke(realclass, args);
} catch (Exception e) {
}
System.out.println("end the login validate");
return obj;
} else {
obj = method.invoke(realclass, args);
return obj;
}

}

}

public static void main(String[] args) {
DynaProxyCustomerLoginHandler loginHandler = new DynaProxyCustomerLoginHandler();
CustomerLoginAction customerLoginAction = new CustomerLoginAction();
LoginAction loginAction = (LoginAction)loginHandler.binding(customerLoginAction);
loginAction.execute();
}