[Design pattern]: 设计模式相关系列
介绍
概念: 将一个复杂对象的构建与它的表示分离，使得同样的构建过程可以创建不同的表示。
例如: 衣服制造厂(实体)有制造衣服的功能,每种衣服的制造流程都不相同,因此把制造衣服这个复杂且可变的功能分离出来.
使用场景: 实体的某个功能复杂且不只有一种
好处: 功能的扩展不影响实体,实体更加内聚,与可变的部分耦合度低
CODE
生产过程接口
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| package note.com.builder;
public interface Builder {
public String build(Factory factory);
}
|
生产1过程
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| package note.com.builder;
public class Builder1 implements Builder{
public String build(Factory factory) {
String clothes = factory.getOne1()+factory.getTwo2()+factory.getThree1()+factory.getFour1();
return clothes;
}
}
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生产2过程
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| package note.com.builder;
public class Builder2 implements Builder{
public String build(Factory factory) {
String clothes = factory.getOne2()+factory.getTwo1()+factory.getFour1();
return clothes;
}
}
|
衣服工厂实体
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| package note.com.builder;
public class Factory {
private String one1 = "纺织布";
private String one2 = "尼龙布";
private String two1 = "裁剪";
private String two2 = "上色";
private String three1 = "加领";
private String four1 = "缝合";
public String build(Builder builder){
String clothes = builder.build(this);
System.out.println("生产过程:"+clothes);
return clothes;
}
public String getOne1() {
return one1;
}
public void setOne1(String one1) {
this.one1 = one1;
}
public String getOne2() {
return one2;
}
public void setOne2(String one2) {
this.one2 = one2;
}
public String getTwo1() {
return two1;
}
public void setTwo1(String two1) {
this.two1 = two1;
}
public String getTwo2() {
return two2;
}
public void setTwo2(String two2) {
this.two2 = two2;
}
public String getThree1() {
return three1;
}
public void setThree1(String three1) {
this.three1 = three1;
}
public String getFour1() {
return four1;
}
public void setFour1(String four1) {
this.four1 = four1;
}
}
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测试类
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| package note.com.builder;
public class BuilderTest {
public static void main(String[] args) {
Factory factory = new Factory();
Builder builder1 = new Builder1();
Builder builder2 = new Builder2();
factory.build(builder1);
factory.build(builder2);
}
}
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结果
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| 生产过程:纺织布上色加领缝合
生产过程:尼龙布裁剪缝合
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由此,工厂的生产过程与工厂进行分离,并且每次增加新衣服的生产都只需要增加Builder的实现就可以了.