《大話設計模式》java實作之代理模式

UML圖，為了展示核心的代理模式類關系，這裡細節的部分，比如Pursui和SchoolGirl的關系就不畫了，代理模式的核心為代理類和被代理類實作的是同一個接口，可以詳細控制通路某個類的方法，在調用方法前做前置處理，在調用方法後做後置處理

代碼結構

public class Client {
    public static void main(String[] args) {
        SchoolGirl jiaojiao = new SchoolGirl("李嬌嬌");

        Proxy dali = new Proxy(jiaojiao);

        dali.giveDolls();
        dali.giveFlowers();
    }
}
           

public interface IGiveGift {
    void giveDolls();
    void giveFlowers();
}
           

public class Proxy implements IGiveGift {
    private Pursuit gg;

    public Proxy(SchoolGirl mm) {
        gg = new Pursuit(mm);
    }

    @Override
    public void giveDolls() {
        if(gg != null) {
            gg.giveDolls();
        }
    }

    @Override
    public void giveFlowers() {
        if(gg != null) {
            gg.giveFlowers();
        }
    }

}
           

public class Pursuit implements IGiveGift {
    private SchoolGirl schoolGirl;

    public Pursuit(SchoolGirl schoolGirl) {
        super();
        this.schoolGirl = schoolGirl;
    }

    @Override
    public void giveDolls() {
        System.out.println(schoolGirl.getName() + ", 送你洋娃娃");
    }

    @Override
    public void giveFlowers() {
        System.out.println(schoolGirl.getName() + ", 送你鮮花");
    }

}
           

public class SchoolGirl {
    private String name;

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public SchoolGirl(String name) {
        super();
        this.name = name;
    }

}
           

運作結果