1. 经典Builder模式
经典Buider模式中有四个角色：
要建造的产品Product -- 组装的电脑
抽象的Builder -- 装CPU、内存条、硬盘等抽象的步骤
Builder的具体实现ConcreteBuilder -- 对上述抽象步骤的实现，比如装i5CPU、8G内存条、1T硬盘
使用者Director -- 电脑装机人员
Computer类
public class Computer {
/*CPU*/
private String CPU;
/*内存*/
private String memory;
/*硬盘*/
private String hardDisk;
/*键盘*/
private String keyboard;
/*鼠标*/
private String mouse;
public String getCPU() {
return CPU;
}
public void setCPU(String CPU) {
this.CPU = CPU;
}
public String getMemory() {
return memory;
}
public void setMemory(String memory) {
this.memory = memory;
}
public String getHardDisk() {
return hardDisk;
}
public void setHardDisk(String hardDisk) {
this.hardDisk = hardDisk;
}
public String getKeyboard() {
return keyboard;
}
public void setKeyboard(String keyboard) {
this.keyboard = keyboard;
}
public String getMouse() {
return mouse;
}
public void setMouse(String mouse) {
this.mouse = mouse;
}
@Override
public String toString() {
return "Computer{" +
"CPU='" + CPU + '\'' +
", memory='" + memory + '\'' +
", hardDisk='" + hardDisk + '\'' +
", keyboard='" + keyboard + '\'' +
", mouse='" + mouse + '\'' +
'}';
}
}
抽象的电脑组装过程的Builder类
public interface ComputerConfigBuilder {
void setCPU();
void setMemery();
void setHardDisk();
void setKeyboard();
void setMouse();
Computer getComputer();
}
低配版的套餐LowConfigBuilder ，实现ComputerConfigBuilder
public class LowConfigBuilder implements ComputerConfigBuilder {
private Computer mComputer;
public LowConfigBuilder(){
this.mComputer = new Computer();
}
@Override
public void setCPU() {
mComputer.setCPU("i5");
}
@Override
public void setMemery() {
mComputer.setMemory("8G");
}
@Override
public void setHardDisk() {
mComputer.setHardDisk("500G");
}
@Override
public void setKeyboard() {
mComputer.setKeyboard("薄膜键盘");
}
@Override
public void setMouse() {
mComputer.setMouse("有线鼠标");
}
@Override
public Computer getComputer() {
return mComputer;
}
}
创建一个高配版的套餐
public class HighConfigBuider implements ComputerConfigBuilder {
private Computer mComputer;
public HighConfigBuider(){
this.mComputer = new Computer();
}
@Override
public void setCPU() {
mComputer.setCPU("i7");
}
@Override
public void setMemery() {
mComputer.setMemory("16G");
}
@Override
public void setHardDisk() {
mComputer.setHardDisk("1T");
}
@Override
public void setKeyboard() {
mComputer.setKeyboard("机械键盘");
}
@Override
public void setMouse() {
mComputer.setMouse("无线鼠标");
}
@Override
public Computer getComputer() {
return mComputer;
}
}
一名装机人员Director
public class Director {
private ComputerConfigBuilder mBuilder;
public void setBuilder(ComputerConfigBuilder builder){
this.mBuilder = builder;
}
public void createComputer(){
mBuilder.setCPU();
mBuilder.setMemery();
mBuilder.setHardDisk();
mBuilder.setKeyboard();
mBuilder.setMouse();
}
public Computer getComputer(){
return mBuilder.getComputer();
}
}
先创建一个低配版的
Director director = new Director();//创建装机人员
director.setBuilder(new LowConfigBuilder()); //告诉装机人员电脑配置，这里为低配版
director.createComputer(); //装机人员开始组装
Computer computer = director.getComputer(); //从装机人员获取组装好的电脑
System.out.print("电脑配置：" + computer.toString()); //查看电脑配置
--------------------------------------
输出结果：
电脑配置：Computer{CPU='i5', memory='8G', hardDisk='500G', keyboard='薄膜键盘', mouse='有线鼠标'}
--------------------------------------
高配版的
Director director = new Director();//创建装机人员
director.setBuilder(new HighConfigBuider());
director.createComputer();
Computer computer = director.getComputer();
System.out.print("电脑配置：" + computer.toString());
--------------------------------------
输出结果：
电脑配置：Computer{CPU='i7', memory='16G', hardDisk='1T', keyboard='机械键盘', mouse='无线鼠标'}
--------------------------------------
2. 变种Builder模式
创建一个不可变的Person对象，这个Person可以拥有以下几个属性：名字、性别、年龄、职业、车、鞋子、衣服、钱、房子。其中名字和性别是必须有的。
public class Person {
/*名字（必须）*/
private final String name;
/*性别（必须）*/
private final String gender;
/*年龄（非必须）*/
private final String age;
/*鞋子（非必须）*/
private final String shoes;
/*衣服（非必须）*/
private final String clothes;
/*钱（非必须）*/
private final String money;
/*房子（非必须）*/
private final String house;
/*汽车（非必须）*/
private final String car;
/*职业（非必须）*/
private final String career;
private Person(Builder builder) {
this.name = builder.name;
this.gender = builder.gender;
this.age = builder.age;
this.shoes = builder.shoes;
this.clothes = builder.clothes;
this.money = builder.money;
this.house = builder.house;
this.car = builder.car;
this.career = builder.career;
}
public static class Builder {
private final String name;
private final String gender;
private String age;
private String shoes;
private String clothes;
private String money;
private String house;
private String car;
private String career;
public Builder(String name, String gender) {
this.name = name;
this.gender = gender;
}
public Builder age(String age) {
this.age = age;
return this;
}
public Builder car(String car) {
this.car = car;
return this;
}
public Builder shoes(String shoes) {
this.shoes = shoes;
return this;
}
public Builder clothes(String clothes) {
this.clothes = clothes;
return this;
}
public Builder money(String money) {
this.money = money;
return this;
}
public Builder house(String house) {
this.house = house;
return this;
}
public Builder career(String career) {
this.career = career;
return this;
}
public Person build() {
return new Person(this);
}
}
}
Person的创建
Person person = new Person.Builder("张三","男")
.age("12")
.money("1000000")
.car("宝马")
.build();
