java 23 种设计模式-04-构建者模式 builder

目录

建造者模式

建造者模式（Builder Pattern）使用多个简单的对象一步一步构建成一个复杂的对象。
这种类型的设计模式属于创建型模式，它提供了一种创建对象的最佳方式。

比如：StringBuilder

实际案例

类信息概览：

类名	说明
Main.java	方法的总入口
PersonGirlBuilder.java
PersonBoyBuilder.java
Person.java
PersonBuilder.java
PersonDirector.java

定义

• PersonGirlBuilder.java

package com.ryo.design.pattern.note.builder;

/**
 * Created by bbhou on 2017/8/9.
 */
public class PersonGirlBuilder implements PersonBuilder {
    @Override
    public String buildName() {
        return "rose";
    }

    @Override
    public int buildAge() {
        return 19;
    }

    @Override
    public String buildSex() {
        return "girl";
    }
}

• PersonBoyBuilder.java

package com.ryo.design.pattern.note.builder;

/**
 * Created by bbhou on 2017/8/9.
 */
public class PersonBoyBuilder implements PersonBuilder {
    @Override
    public String buildName() {
        return "jack";
    }

    @Override
    public int buildAge() {
        return 20;
    }

    @Override
    public String buildSex() {
        return "boy";
    }
}

• Person.java

package com.ryo.design.pattern.note.builder;

import lombok.Data;

/**
 * Created by bbhou on 2017/8/9.
 */
@Data
public class Person {

    /**
     * 名称
     */
    private String name;

    /**
     * 年龄
     */
    private int age;

    /**
     * 性别
     */
    private String sex;

}

• PersonBuilder.java

package com.ryo.design.pattern.note.builder;

/**
 * Created by bbhou on 2017/8/9.
 */
public interface PersonBuilder {

    /**
     * 构建名称
     * @return
     */
    String buildName();

    /**
     * 构建年龄
     * @return
     */
    int buildAge();

    /**
     * 构建性别
     * @return
     */
    String buildSex();

}

• PersonDirector.java

package com.ryo.design.pattern.note.builder;


/**
 * Created by bbhou on 2017/8/9.
 */
public class PersonDirector {

    private PersonBuilder personBuilder;

    public PersonDirector(PersonBuilder personBuilder) {
        this.personBuilder = personBuilder;
    }

    /**
     * 创建一个人
     * @return
     */
    Person createPerson() {
        Person person = new Person();
        person.setAge(personBuilder.buildAge());
        person.setName(personBuilder.buildName());
        person.setSex(personBuilder.buildSex());
        return person;
    }

}

测试

• Main.java

/*
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
 * Copyright (c) 2012-2018. houbinbini Inc.
 * design-pattern All rights reserved.
 */

package com.ryo.design.pattern.note.builder;

/**
 * 
 
 *
 * 
 Created: 2018/5/9 下午7:45  
 * 
 Project: design-pattern  
 *
 * @author houbinbin
 * @version 1.0
 * @since JDK 1.7
 */
public class Main {

    public static void main(String[] args) {
        PersonDirector personDirector = new PersonDirector(new PersonBoyBuilder());
        Person person = personDirector.createPerson();
        System.out.println(person);
    }

}

• 测试结果

Person(name=jack, age=20, sex=boy)

实现方式

UML & Code

UML

UML 图示如下

Code

代码地址

建造者模式

系列导航

系列导航