java实现静态代理

import javax.sound.sampled.Port;


interface Person
{
    public void sayHello() ;
}

class Student implements Person
{
    public void sayHello()
    {
        System.out.println( "学生向大家Say Hello" ) ;
    }
}

//使用静态代理，最大的问题，代理类只能为一个接口服务，扩展性不行
class ProxyPerson implements Person
{
    private Person per ;

    public ProxyPerson( Person per )
    {
        this.per =  per ;
    }

    public void sayHello()
    {
        System.out.println( "Say Hello前先让校长讲两句" ) ;
        this.per.sayHello() ;
        System.out.println( "Say Hello后再让校长臭得色几句" ) ;
    }

}

public class Test
{
    public static void main( String[] args )
    {
        Person per = new ProxyPerson( new Student() ) ;
        per.sayHello() ;
    }
}