Java学习笔记——设计模式之九.建造者模式

 建造者模式（Builder）,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。

Product类：

 package cn.happy.design_pattern._09builder;
 
 import java.util.ArrayList;
 import java.util.List;
 
 public class Product {
 
     List<String> parts = new ArrayList<>();
 
     public void add(String part){
         parts.add(part);
     }
 
     public void show(){
         System.out.println("创建产品...");
         for (String item : parts) {
             System.out.println(item);
         }
     }
 }

Builder类：

 package cn.happy.design_pattern._09builder;
 
 public abstract class Builder {
 
     public abstract void BuildPartA();
     public abstract void BuildPartB();
     public abstract Product GetResult();
 }

Builder子类：

 package cn.happy.design_pattern._09builder;
 
 public class ConcreteBuilder1 extends Builder {
 
     private Product product = new Product();
     @Override
     public void BuildPartA() {
         product.add("部件A");
 
     }
 
     @Override
     public void BuildPartB() {
         product.add("部件B");
 
     }
 
     @Override
     public Product GetResult() {
         // TODO Auto-generated method stub
         return product;
     }
 
 }
 
 public class ConcreteBuilder2 extends Builder {
 
     private Product product = new Product();
     @Override
     public void BuildPartA() {
         product.add("部件X");
 
     }
 
     @Override
     public void BuildPartB() {
         product.add("部件Y");
 
     }
 
     @Override
     public Product GetResult() {
         // TODO Auto-generated method stub
         return product;
     }
 
 }

Director类：

 package cn.happy.design_pattern._09builder;
 
 public class Director {
 
     public void Construct(Builder builder){
         builder.BuildPartA();
         builder.BuildPartB();
     }
 }

测试类：

 package cn.happy.design_pattern._09builder;
 
 public class Mmain {
     public static void main(String[] args) {
         Director director = new Director();
         Builder b1 = new ConcreteBuilder1();
         Builder b2 = new ConcreteBuilder2();
         director.Construct(b1);
         b1.GetResult().show();
         director.Construct(b2);
         b2.GetResult().show();
     }
 }