map转换成JSON的3种方法

map转换成JSON的3种方法

1. json-lib

<dependency>
		<groupId>net.sf.json-lib</groupId>
    	<artifactId>json-lib</artifactId>
    	<version>2.4</version>
    	<classifier>jdk15</classifier>
</dependency>

import java.util.HashMap;
import java.util.Map;

import net.sf.json.JSONObject;

public class aaa {
	  public static void main(String[] args) {
	        Map map = new HashMap();
	        map.put("msg", "yes");//map里面装有yes
	        JSONObject jsonObject = JSONObject.fromObject(map);
	        System.out.println("输出的结果是：" + jsonObject);
	        //3、将json对象转化为json字符串
	        String result = jsonObject.toString();
	        System.out.println(result);
	    }
}

注意这个依赖只适合java5，并不适合java6；

2. alibaba

JSONUtils.toJSONString(requestMap); com.alibaba.fastjson.JSON

<!-- https://mvnrepository.com/artifact/com.alibaba/fastjson -->
<dependency>
    <groupId>com.alibaba</groupId>
    <artifactId>fastjson</artifactId>
    <version>1.2.41</version>
</dependency>

3. google

new Gson().toJson(param); com.google.gson.2.2.2.jar JAR包下载

maven坐标

<!-- https://mvnrepository.com/artifact/com.google.code.gson/gson -->
<dependency>
    <groupId>com.google.code.gson</groupId>
    <artifactId>gson</artifactId>
    <version>2.3.1</version>
</dependency>