使用fastjson进行json字符串和List的转换

  使用fastjson进行自定义类的列表和字符串转换

  1.环境

  jdk1.8,fastjson

  2.pom.xml

	4.0.0

	co.neutron.json
	fastjson
	0.0.1-SNAPSHOT
	jar

	fastjson
	http://maven.apache.org

	
		UTF-8
	

	
		
			junit
			junit
			4.8
			test
		
		
			com.alibaba
			fastjson
			1.2.12
		
		
			org.slf4j
			slf4j-log4j12
			1.7.2
		
	

  3.实体类

package co.neutron.json.fastjson.entity;

public class User {
	private int id;
	private String name;
	private int age;
	
	public User() {
		super();
	}

	public User(int id, String name, int age) {
		super();
		this.id = id;
		this.name = name;
		this.age = age;
	}

	public int getId() {
		return id;
	}

	public void setId(int id) {
		this.id = id;
	}

	public String getName() {
		return name;
	}

	public void setName(String name) {
		this.name = name;
	}

	public int getAge() {
		return age;
	}

	public void setAge(int age) {
		this.age = age;
	}

	@Override
	public String toString() {
		return "User [id=" + id + ", name=" + name + ", age=" + age + "]";
	}
	
}

  4.测试类

package co.neutron.json.fastjson;

import java.util.ArrayList;
import java.util.List;

import org.junit.Assert;
import org.junit.Test;

import com.alibaba.fastjson.JSON;

import co.neutron.json.fastjson.entity.User;

public class ArrayListTest {

	/*
	 * 测试内容如下
	 * 1.将User类型数组转换成json字符串
	 * 2.将json字符串转换成为User数组
	 */
	@Test
	public void testArray2StringAndString2List() {
		User user1 = new User(1, "张1", 11);
		User user2 = new User(2, "张2", 12);
		User user3 = new User(3, "张3", 13);
		User user4 = new User(4, "张4", 14);
		User[] users = {user1, user2, user3, user4};
		
		/* 
		 * 将数组转换为Json字符串
		 * result:
		 * [{"age":11,"id":1,"name":"张1"},{"age":12,"id":2,"name":"张2"},
		 * {"age":13,"id":3,"name":"张3"},{"age":14,"id":4,"name":"张4"}]
		 */
		String userStr = JSON.toJSONString(users);
		
		/*
		 * 将Json字符串转换为List
		 * result
		 * User [id=1, name=张1, age=11]
		   User [id=2, name=张2, age=12]
		   User [id=3, name=张3, age=13]
		   User [id=4, name=张4, age=14]
		 */
		List userList = JSON.parseArray(userStr, User.class);
		userList.stream().forEach(System.err::println);
	}
	
	/**
	 * 测试包装类型的List转换为json字符串
	 */
	@Test
	public void testList2String() {
		List longs = new ArrayList();
		longs.add(1L);
		longs.add(2L);
		longs.add(3L);
		String actual = JSON.toJSONString(longs);
		Assert.assertEquals("[1,2,3]", actual);
	}

}