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（ps：简单理解隐藏内部的建造过程和细节，方便创建复杂的对象）

• UML

  
  

• code

  /**
   * @Desc 水果接口
   */
  public interface FruitBuilder {
      /**
       * 创建水果
       */
      void createFruit();
  
      /**
       * 水果颜色
       */
      void buildColor() ;
  
      /**
       * 水果形状
       */
      void buildShape() ;
  
      /**
       * 创建水果
       * @return
       */
      Fruit getFruit();
  }
  

  @Data
  public class Fruit {
      
      private String name;
  
      private String color;
      
      private String shape;
  
      public Fruit(String name) {
          this.name = name;
      }
  
      public Fruit() {
      }
  }
  

public class BananaBuilder implements FruitBuilder {

    private Fruit fruit;

    @Override
    public void createFruit() {
        this.fruit = new Fruit("香蕉") ;
    }

    @Override
    public void buildColor() {
        this.fruit.setColor("红色");
    }

    @Override
    public void buildShape() {
        this.fruit.setShape("圆形");
    }

    @Override
    public Fruit getFruit() {
        return fruit;
    }
}

public class AppleBuilder implements FruitBuilder {

    private Fruit fruit;

    @Override
    public void createFruit( ) {
        this.fruit= new Fruit("苹果") ;
    }

    @Override
    public void buildColor() {
        this.fruit.setColor("蓝色");
    }

    @Override
    public void buildShape() {
        this.fruit.setShape("椭圆形");
    }

    @Override
    public Fruit getFruit() {
        return fruit;
    }
}

public class Soul {
    
    public Fruit createFruit(FruitBuilder fruitBuilder){
        fruitBuilder.createFruit();
        fruitBuilder.buildColor();
        fruitBuilder.buildShape();
        return fruitBuilder.getFruit();
    }

}

public class Main {

  public static void main(String[] args) {
      Soul soul = new Soul();
      //苹果
      System.out.println("生产了：" + soul.createFruit(new AppleBuilder()));
      System.out.println("----------------------------------------");

      //香蕉
      System.out.println("生产了：" + soul.createFruit(new BananaBuilder()));
  }
}

建造者模式与工厂模式类似，但是建造者模式能应对更加复杂的创建过程。