JAVA设计模式之建造者模式

建造者模式：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。

简单例子：

public class Product 
{
    private String partA;
    private String partB;
    
    public void setPartA(String partA) 
    {
        this.partA = partA;
    }

    public void setPartB(String partB)
    {
        this.partB = partB;
    }
    
    @Override
    public String toString()
    {
        return "[partA = " + partA + ", partB = " + partB + "]";
    }
}

public interface Factory 
{
    public void init();
    public void buildPartA();
    public void buildPartB();
    public Product getProduct();
}

public class Factory1A2B implements Factory
{
    private Product product;
    
    @Override
    public void init() 
    {
        product = new Product();
    }
    
    @Override
    public void buildPartA() 
    {
        product.setPartA("1");
    }

    @Override
    public void buildPartB() 
    {
        product.setPartB("2");
    }

    @Override
    public Product getProduct() 
    {
        return product;
    }
}

public class Director
{
    private Factory factory = new Factory1A2B();
    
    public Product newProduct()
    {
        factory.init();
        factory.buildPartA();
        factory.buildPartB();
        return factory.getProduct();
    }
}

public class Test 
{
    public static void main(String[] args)
    {
        Director director = new Director();
        System.out.println(director.newProduct());
    }
}