Java 设计模式Builder模式

Dog类

/*
 * 构建者模式
 */
public class Dog {

    private final String name;

    private final String sex;

    private final String age;

    private Dog(Builder builder)
    {
        this.name = builder.name;
        this.sex = builder.sex;
        this.age = builder.age;
    }

    @Override
    public String toString() {
        return "name=" + name + ", sex=" + sex + ", age=" + age;
    }

    public static class Builder{

        private  String name;

        private  String sex;

        private  String age;

//        public Builder()
//        {
//
//        }

        public Builder name(String name)
        {
            this.name = name;
            return this;
        }

        public Builder sex(String sex)
        {
            this.sex = sex;
            return this;
        }

        public Builder age(String age)
        {
            this.age = age;
            return this;
        }

        public Dog build()
        {
            return new Dog(this);
        }
    }
}

测试类

public class TestDogBuilder {

    public static void main(String[] args)
    {
        Dog dog = new Dog.Builder().name("笨笨").age("20").sex("小公狗").build();
        System.out.println(dog);
    }
}

运行结果

name=笨笨, sex=小公狗, age=20