JSONObject obj = new JSONObject();
{
obj.put("key1", "value1");
obj.put("key2", "value2");
obj.put("key3", "value3");
}
Map<String, String> params = JSONObject.parseObject(obj.toJSONString(), new TypeReference<Map<String, Object>>(){});
System.out.println(params);

//输出：{key3=value3, key2=value2, key1=value1}