静态代理

public interface Subject {

    public void Rread();
}

public class ReadSubject implements Subject{
    //这里是单例用法,这个类主要是为了给ResultSubject提供Subject实例
    static ReadSubject rs=new ReadSubject();
    private ReadSubject(){
        
    }
    public static ReadSubject getReadSubject(){
        return rs;
    }
    public static Subject getSubject(){
        return new ReadSubject();
    }

    @Override
    public void Rread() {
        System.out.println("生成方法的中间类");
    }
}

public class StaticProxy implements Subject{
    //这个静态代理类用来重写接口Subject的Rread方法
    private Subject rs=null;
    //这个是构造函数为了使需要重写类与该类建立联系，达到重写Rread的目的
    //具体是new StaticProxy(rs.getSubject())
    public StaticProxy(Subject rs){
        this.rs=rs;
         
    }
    @Override
    public void Rread() {
        System.out.println("hello world");
    }

}

public class ResultSubject{
    ReadSubject rs=ReadSubject.getReadSubject();
    public  Subject s=null;
    public ResultSubject(){
        s=rs.getSubject();//这样将不会重写Subject的Rread方法
    
    }
}

public class ResultSubject{
    ReadSubject rs=ReadSubject.getReadSubject();
    public  Subject s=null;
    public ResultSubject(){
        //这样利用静态代理可以达到重写的目的
        s=new StaticProxy(rs.getSubject());
    
    }
}

public class Test {
    public static void main(String[] args) {
//        Subject subject=new StaticProxy(new ResultSubject());
//        subject.Rread();
        ResultSubject rs=new ResultSubject();
　　　　　Subject s=rs.s;
       　　s.Rread();
    }
}