Java中Builder设计模式用法分享

Builder设计模式简介

 主要用于解决对象构建比较的复杂的情况
   如:
     构造超出构造函数的表示,此时我们可以使用Builder模式,
	 使构建变的简单明了 

Builder设计模式的实现思路：
    只需在Set属性时,返回当前对象
	使用此种模式,即可实现Builder设计模式

Student实体定义

package com.java265.model;
import java.util.list;
 
public class Student {
 
    private String name;
    private int age;
    private List<String> language;
 
    public static class Builder {
 
        private String name;
        private int age;
        private List<String> language;
 
        public Builder name(String name) {
            this.name = name;
            return this;
        }
 
        public Builder age(int age) {
            this.age = age;
            return this;
        }
 
        public Builder language(List<String> language) {
            this.language = language;
            return this;
        }
 
        public Student build() {
            return new Student(this);
        }
 
    }
 
    private Student(Builder builder) {
        name = builder.name;
        age = builder.age;
        language = builder.language;
    }
 
    @Override
    public String toString() {
        return "Student{" +
                "name='" + name + '\'' +
                ", age=" + age +
                ", language=" + language +
                '}';
    }
}

Builder设计模式的使用示例

package com.java265.model;
import java.util.Arrays;
public class TestStudent {
    public static void main(String[] args) {
        Student s = new Student.Builder()
			.name("java265")
			.age(22)
			.language(Arrays.asList("chinese","english"))
			.build();
 
		//Student{name='java265', age=22, language=[chinese, english]}
        System.out.println(s);
 
        // Classic way to create an object
		/*
		Student s = new Student();
        s.setName("java265");
        s.setAge(22);
        s.setLanguage(Arrays.asList("chinese","english"));
		*/
 
    }
 
}