深入设计模式-4.建造者模式

1.简介

将一个复杂的对象的构建与他的表示分离，使得同样的构建过程可以创建不同的表示，这样的设计模式被称为建造者模式。创建者模式主要是为了将对象的构建装配与他的表现分离。譬如生产两种运动鞋阿迪和耐克，虽然生产材料款式不同，但是生产的过程都是将鞋底，鞋面，鞋带装在一起。这样对象就有了共性，我们可以抽象出一个制造者（建造者），将不同鞋的生产过程‘告诉’这个制造者，这样这个制造者就能制造出不同的鞋子。

2.结构

3.示例

//产品对象

public class Shoe { //鞋带 private String shoelace; //鞋底 private String sole; //鞋面 private String vamp; //LOGO private String logo; public String getLogo() { return logo; }   public void setLogo(Stringlogo) { this.logo= logo; }   public String getShoelace() { return shoelace; }   public void setShoelace(Stringshoelace) { this.shoelace= shoelace; }   public String getSole() { return sole; }   public void setSole(Stringsole) { this.sole= sole; }   public String getVamp() { return vamp; }   public void setVamp(Stringvamp) { this.vamp= vamp; }   }//阿迪鞋

public class AdidasShoe extends Shoe {   }

//耐克鞋

public class NikeShoe extends Shoe {   }

//抽象建造者

public interface Builder { public void installShoelace(); public void installSole(); public void installVamp(); public void installLogo(); public Shoe getShoe(); }//阿迪建造者

public class AdidasShoeBuilderimplementsBuilder { private Shoe shoe; public AdidasShoeBuilder() { // TODO Auto-generated constructor stub shoe = new AdidasShoe(); } @Override public void installShoelace() { // TODO Auto-generated method stub shoe.setShoelace("blue shoelace"); }   @Override public void installSole() { // TODO Auto-generated method stub shoe.setSole("comfortable sole"); }   @Override public void installVamp() { // TODO Auto-generated method stub shoe.setVamp("black vamp"); }   @Override public void installLogo() { // TODO Auto-generated method stub shoe.setLogo("ADIDAS"); }   public Shoe getShoe() { return shoe; }           }//耐克建造者

public class NikeShoeBuilderimplementsBuilder { private Shoe shoe; public NikeShoeBuilder(){ shoe = new NikeShoe(); }   @Override public void installShoelace() { // TODO Auto-generated method stub shoe.setShoelace("red shoelace"); }   @Override public void installSole() { // TODO Auto-generated method stub shoe.setSole("comfortable sole"); }   @Override public void installVamp() { // TODO Auto-generated method stub shoe.setVamp("black vamp"); }   @Override public void installLogo() { // TODO Auto-generated method stub shoe.setLogo("NIKE"); }   public Shoe getShoe() { return shoe; }         }//鞋建造者

public class ShoeBuilder { private Builder builder ; public ShoeBuilder(Builder builder){ this.builder= builder; } public Builder install(){ builder.installShoelace(); builder.installSole(); builder.installVamp(); builder.installLogo(); return builder; } }

//主函数

public class Main { public static void main(String[] args) { // TODO Auto-generated method stub Builder adBuilder = new AdidasShoeBuilder(); Builder nikeBuilder = new NikeShoeBuilder(); ShoeBuilder builder = new ShoeBuilder(nikeBuilder); Shoe nikeShoe = builder.install().getShoe(); System.out.println(" a"+ nikeShoe.getShoelace()+""+ nikeShoe.getLogo()+" shoe"); builder = new ShoeBuilder(adBuilder); Shoe adShoe = builder.install().getShoe(); System.out.println(" a"+ adShoe.getShoelace()+""+ adShoe.getLogo()+" shoe"); } }