Builder 构建器

Builder 构建器

分离复杂对象的构建和表示
Builder 构建器 - 图1
创建一个构建器接口，有builderPart1、builderPart2等构建复杂对象各个部分的方法，以及builder返回复杂对象的方法。写几个不同的构建器接口的实现类。实现简单或者复杂的构建。

  1. //等待被构建的复杂对象
  2.  public class Terrain {
  3.     wall w;
  4.     fort f;
  5.     mine m;
  6. }
  7. class Wall {
  8.     int a,b,c,d;
  9.     public wall(int a,int b,int c,int d){
  10.     this.a = a;
  11.     this.b = b;
  12.     this.c = c;
  13.     this.d=d;
  14.     } 
  15. }
  16. // fort及mine 同 wall
  17. //builder 接口
  18. public interface BuilderTerrain {
  19.     BuilderTerrain builderWall();   
  20.     BuilderTerrain builderFort();
  21.     BuilderTerrain builderMine();
  22.     Terrain builder();
  23. }
  24. //simpleBuilder 简单的构建
  25. public class SimpleBuilder implements BuilderTerrain{
  26.     Terrain terrain = new Terrain();
  27.     public BuilderTerrain builderWall(){
  28.         terrain.w = new  Wall(10,10,10,10);
  29.         return this;
  30.     }
  31.      public BuilderTerrain builderFort(){
  32.         terrain.f = new  Fort(10,10,10,10);
  33.           return this;
  34.     }
  35.      public BuilderTerrain builderMine(){
  36.         terrain.m = new  Mine(10,10,10,10);
  37.           return this;
  38.     }
  39.     public Terrain builder(){
  40.         return this.terrain;
  41.     }
  42. }
  43. //complexBuilder复杂的构建，与simpleBuilder类似，只是builderPart方法实现略有不同。
  44. //main方法测试
  45. public static void main(String[] args){
  46.     SimpleBuilder simple = new SimpleBuilder();
  47.   Terrain terrain  =simple.builderWall().builderFort().builderMine().builder();
  48. }