map转成json字符串

用maven引入fastjson jar包

<dependency>
   <groupId>com.alibaba</groupId>
   <artifactId>fastjson</artifactId>
   <version>1.2.24</version>
</dependency>

Map map=new HashMap();
map.put("page_size","10");
map.put("page_index","1");
String  param= JSON.toJSONString(map);

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		Map<String, Object> resultMap = new HashMap<>();
        resultMap.put("type", type);
        resultMap.put("id", 10);
        resultMap.put("name", "name");
        JSONArray jArray = new JSONArray();
        jArray.add(resultMap);
        String str = jArray.toString();