我使用jackson提供的对象Map器来解析我的json消息。
下面的代码适用于jsonmsg1，但不适用于jsonmsg2，因为它包含双引号。

ObjectMapper objMapper = new ObjectMapper();
JsonNode rootNode = objMapper.rootTree(jsonMessage);

jsonMsg1 ->
{
"key1": "Value1",
"key2":{
  "key2_1": "Value2_1"
  "key2_2": "Value2_2"
       }
}";

jsonMsg2 -> 
{
"key1": "Value1",
"key2":"{
  "key2_1": "Value2_1",
  "key2_2": "Value2_2",
       }"
}

当我尝试解析jsonmsg2-->

com.fasterxml.jackson.core.JsonParserException: Unexpected cjaracter ('k' (code 109)): was expecting comma to separate OBJECT entries