建造者模式

盖房子项目需求

建造者模式也叫做生成器模式

1.需要建房子：这一过程为打桩、砌墙、封顶

2.房子有各种各样的，比如普通房，高楼、别墅，各种房子的过程虽然一样，但是要求不相同。

3.请编写程序，完成需求。

传统方式解决盖房子

package com.builder;
 
public abstract class AbstractHouse {
    //打地基
    public abstract void buildBasic();
    //砌墙
    public abstract void buildWalls();
    //封顶
    public abstract void roofed();
    //依次调用者三个方法
    public void build(){
        buildBasic();
        buildWalls();
        roofed();
    }
}

package com.builder;
 
public class CommonHouse extends AbstractHouse {
    @Override
    public void buildBasic() {
        System.out.println("普通房子打地基");
    }
 
    @Override
    public void buildWalls() {
        System.out.println("普通房子砌墙");
    }
 
    @Override
    public void roofed() {
        System.out.println("普通房子封顶");
    }
}

package com.builder;
 
public class HighHouse extends AbstractHouse {
    @Override
    public void buildBasic() {
        System.out.println("高楼房子打地基");
    }
 
    @Override
    public void buildWalls() {
        System.out.println("高楼房子砌墙");
    }
 
    @Override
    public void roofed() {
        System.out.println("高楼房子封顶");
    }
}

package com.builder;
 
public class Client {
    public static void main(String[] args) {
        CommonHouse commonHouse = new CommonHouse();
        commonHouse.build();
    }
}

运行结果:

普通房子打地基
普通房子砌墙
普通房子封顶

传统方式解决盖房子需求问题分析

建造者模式的基本介绍

建造者模式的四个角色

package com.builder.improve;
//产品---->product
public class House {
    private String base;
    private String wall;
    private String roofed;
 
    public String getBase() {
        return base;
    }
 
    public void setBase(String base) {
        this.base = base;
    }
 
    public String getWall() {
        return wall;
    }
 
    public void setWall(String wall) {
        this.wall = wall;
    }
 
    public String getRoofed() {
        return roofed;
    }
 
    public void setRoofed(String roofed) {
        this.roofed = roofed;
    }
}

package com.builder.improve;
//抽象的建造者
public abstract class HouseBuilder {
    protected House house=new House();
 
    //将建造的流程写好，抽象的方法
    public abstract void buildBase();
    public abstract void buildWalls();
    public abstract void buildRoofed();
 
    //建造号房子之后，将产品（房子）返回
    public House buildHouse(){
        return house;
    }
}

package com.builder.improve;
 
/**
 * 下面的建造顺序我是可以根据自己的需要进行改动的
 */
public class CommonHouse extends HouseBuilder {
    @Override
    public void buildBase() {
        System.out.println("普通房子打地基");
    }
 
    @Override
    public void buildWalls() {
        System.out.println("普通房子砌墙");
    }
 
    @Override
    public void buildRoofed() {
        System.out.println("普通房子封底");
    }
}

package com.builder.improve;
 
public class HighBuilding extends HouseBuilder {
    @Override
    public void buildBase() {
        System.out.println("高楼打地基");
    }
 
    @Override
    public void buildWalls() {
        System.out.println("高楼浇筑混凝土墙体");
    }
 
    @Override
    public void buildRoofed() {
        System.out.println("高楼封底了");
    }
}

package com.builder.improve;
 
/**
 * 创建指挥者 指挥具体的建造流程
 * 当然，这里的指挥者是可以有多个的，指挥者可以自己制定建造房子的具体流程
 * 但是使用之前的那种继承方式就不行了
 */
public class HouseDirector {
    HouseBuilder houseBuilder=null;
    //构造器传入 houseBuilder
    public HouseDirector(HouseBuilder houseBuilder) {
        this.houseBuilder = houseBuilder;
    }
    //通过setter方法  传入 houseBuilder
    public void setHouseBuilder(HouseBuilder houseBuilder) {
        this.houseBuilder = houseBuilder;
    }
 
    //如何处理建造房子的流程，交给指挥者
    public House constructHouse(){
        houseBuilder.buildBase();
        houseBuilder.buildWalls();
        houseBuilder.buildRoofed();
        return houseBuilder.buildHouse();
    }
}

package com.builder.improve;
 
public class Client {
    public static void main(String[] args) {
        //盖普通房子
        CommonHouse commonHouse = new CommonHouse();
        HouseDirector houseDirector = new HouseDirector(commonHouse);
        House house = houseDirector.constructHouse();
 
    }
}