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文章目录
  1. 构造器模式

构造器模式

  • 将一个复杂对象的构建与它的表示分离，使同样的构建过程可以创建不同的表示
    Builder
  • 构造器的使用者，构建过程的持有方（算法）
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public interface Director {
    void constuct(PhoneBuilder builder);
}
//制作一个手机
public class PhoneDirector implements Director {
    public void constuct(PhoneBuilder builder){
        builder.buildCamera();
        builder.buildEarphone();
        builder.buildScreen();
    }
}
//打包两个手机
public class PhoneBoxDirector implements Director {
    @Override public void constuct(PhoneBuilder builder) {
        builder.buildCamera();
        builder.buildCamera();
        builder.buildEarphone();
        builder.buildEarphone();
        builder.buildScreen();
        builder.buildScreen();
    }
}
  • 手机构造器builder
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public interface PhoneBuilder {
    void buildScreen();
    void buildEarphone();
    void buildCamera();
    String getResult();
}
public class ApplePhoneBuilder implements PhoneBuilder {
    private int screenCount;
    private int earPhoneCount;
    private int cameraCount;
    @Override public void buildScreen() {
        System.out.println("构建苹果屏幕");
        screenCount++;
    }
    @Override public void buildEarphone() {
        System.out.println("构建苹果耳机");
        earPhoneCount++;
    }
    @Override public void buildCamera() {
        System.out.println("构建苹果摄像头");
        cameraCount++;
    }
    @Override public String getResult() {
        return "苹果手机构建完成，组件数量："+screenCount+" "+earPhoneCount+" "+cameraCount;
    }
}
public class SamsungPhoneBuilder implements PhoneBuilder {
    private int screenCount;
    private int earPhoneCount;
    private int cameraCount;
    @Override public void buildScreen() {
        System.out.println("构建三星屏幕");
        screenCount++;
    }
    @Override public void buildEarphone() {
        System.out.println("构建三星耳机");
        earPhoneCount++;
    }
    @Override public void buildCamera() {
        System.out.println("构建三星摄像头");
        cameraCount++;
    }
    @Override public String getResult() {
        return "三星手机构建完成，组件数量：" + screenCount + " " + earPhoneCount + " " + cameraCount;
    }
}
  • 客户端
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public class App {
    /**
     * 构建器模式，将对象的构建（对象的构造顺序或策略）与表示分离
     * @param args
     */
    public static void main(String[] args) {
        PhoneBuilder appleBuilder=new ApplePhoneBuilder();
        PhoneBuilder samsungPhoneBuilder=new SamsungPhoneBuilder();
        PhoneBuilder[] builders={appleBuilder,samsungPhoneBuilder};
        //第一种构建的策略
        Director direct1=new PhoneDirector();
        for(int i=0;i<builders.length;i++){
            direct1.constuct(builders[i]);//这里是构建的方法，而不存储构建的结果
            System.out.println(builders[i].getResult());//构建的结果由具体的构造器返回
        }
        //第二种构建的策略
        Director direct2=new PhoneBoxDirector();
        for(int i=0;i<builders.length;i++){
            direct2.constuct(builders[i]);//这里是构建的方法，而不存储构建的结果
            System.out.println(builders[i].getResult());//构建的结果由具体的构造器返回
        }
    }
}
文章目录
  1. 构造器模式