建造者（Builder）模式

建造者（Builder）模式

1）建造者模式（Builder Pattern）又叫生成器模式，是一种对象构建模型。它可以将复杂对象的建造过程抽象出来（抽象类别），使这个抽象过程的不同实现方法可以构造出不同表现（属性）的对象
2）建造者模式是一步一步创建一个复杂的对象，它允许用户只通过指定复杂对象的类型和内容就可以构建他们，用户不需要知道内怒具体构造细节

建造者模式的四个角色

1）Product（产品角色）：一个具体的产品对象
2）Builder（抽象建造者）：创建一个Product对象的各个部件指定的接口/抽象类。
3）ConcreteBuilder（具体建造者）：实现接口，构建和装配各个部件
4）Director（指挥者）：构建一个使用Builder接口的对象。它主要是用于创建一个复杂的对象。它主要由两个作用，一是：隔离了客户与对象的生产过程，二是：负责控制产品对象的生产过程

传统方式(耦合性高)

AbstractHouse.java

package com.lucky.builder;

public abstract class AbstractHouse {

    //打地基
    public abstract void buildBaisic();
    //砌墙
    public abstract void buildwalls();
    //封顶
    public abstract void roofed();

    public void build(){
        buildBaisic();
        buildwalls();
        roofed();
    }
}

CommonHouse.java

package com.lucky.builder;

public class CommonHouse extends AbstractHouse {
    @Override
    public void buildBaisic() {
        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");
    }

    @Override
    public void build() {
        super.build();
    }
}

Client.java

package com.lucky.builder;

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

建造者模式

House.java

package com.lucky.builder2;

//产品->Product
public class House {
    private String baise;
    private String wall;
    private String roofed;

    public String getBaise() {
        return baise;
    }

    public void setBaise(String baise) {
        this.baise = baise;
    }

    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;
    }
}

HouseBuilder.java

package com.lucky.builder2;

//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 buildBasic();
    public abstract void buildWalls();
    public abstract void roofed();

    //建造好房子，将产品（房子）返回
    public House buildHouse() {
        return house;
    }
}

CommonHouse.java

package com.lucky.builder2;

public class CommonHouse extends HouseBuilder {

    @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");
    }
}

HeighBuilding.java

package com.lucky.builder2;

import com.lucky.builder2.HouseBuilder;

public class HeighBuilding extends HouseBuilder {
    @Override
    public void buildBasic() {
        System.out.println("高楼的打地基100米");
    }

    @Override
    public void buildWalls() {
        System.out.println("高楼的墙砌20cm");
    }

    @Override
    public void roofed() {
        System.out.println("高楼的透明屋顶");
    }
}

HouseDirector.java

package com.lucky.builder2;

import com.lucky.builder2.House;
import com.lucky.builder2.HouseBuilder;
//指挥者，这里去指定制作流程，返回产品
public class HouseDirector {
    HouseBuilder houseBuilder = null;

    //构造器传入houseBuilder
    public HouseDirector(HouseBuilder houseBuilder) {
        this.houseBuilder = houseBuilder;
    }

    //通过setter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 constractHouse(){
        houseBuilder.buildBasic();
        houseBuilder.buildWalls();
        houseBuilder.roofed();
        return houseBuilder.buildHouse();
    }
}

Client.java

package com.lucky.builder2;

public class Client {
    public static void main(String[] args) {
        //盖普通房子
        CommonHouse commonHouse = new CommonHouse();
        //准备创建房子的指挥者
        HouseDirector houseDirector = new HouseDirector(commonHouse);
//        完成盖房子，返回产品（房子）
        House house = houseDirector.constractHouse();

        HeighBuilding heighBuilding = new HeighBuilding();
        houseDirector.setHouseBuilder(heighBuilding);
        houseDirector.constractHouse();

    }
}