导入jar包

<dependency>
   <groupId>com.alibaba</groupId>
   <artifactId>fastjson</artifactId>
   <version>1.2.41</version>
 </dependency>
1.String 转为JSONObject类型 

  JSONObject value =JSON.parseObject((map.get(key1)));

   2.JSONObject转化为String类型

 

JSON.toJSON(value);

  3.获取JSONobject中数组类型的值

 

JSONObject value =JSON.parseObject((map.get(key1)));
  value.getJSONArray(key).get(int index)

  4.获取JSONobject中String

  

JSONObject value =JSON.parseObject((map.get(key1)));
  value.getJSONObject.getString(key);

  5.将list内容的string转为jsonarray

  

String orderList = orderForm.getItems();
    List<OrderDetail> orderDetailList = null;
    orderDetailList = JSONArray.parseArray(orderList, OrderDetail.class);  //orderDetail为需要转换的实体类