如何使用 ObjectMapper 序列化/反序列化 LogEvent 对象？

Question

Hi I have LogEvent Object used on client side to Log events and I want to send it to to server using REST API. I'm converting LogEvent Object to json string and sending it as payload through REST. On Server side I'm using Groovy and when I try to do objectMapper.readValue() I'm getting following error.

com.fasterxml.jackson.databind.JsonMappingException: Can not find a deserializer for non-concrete Collection type [collection type; class org.apache.logging.log4j.ThreadContext$ContextStack, contains [simple type, class java.lang.String]]

/// Client Side code. 
private final List<LogEvent> eventQueue = new LinkedList<>();
List<LogEvent> logToSend;
            eventsToSend = new ArrayList<>(eventQueue);

   String jsonLogStream = new String();
                ObjectMapper mapperObj = new ObjectMapper();

                try{
                    jsonLogStream =  mapperObj.writeValueAsString(logToSend);
                }catch (IOException e){
                    e.printStackTrace();
                }

                closeableHttpResponse = communicationManager.executeHttpPost(uri, Collections.emptyMap(), new ByteArrayInputStream(jsonLogStream.getBytes()), false);


//// In Groovy 
//         
String logstream = request.getJSON().toString()
//here I'm getting LogEvents converted to json

LogEvent[] events = mapper.readValue(logstream, LogEvent[].class )
// mapper.readvalue giving error mentioned. 

I'm not able to convert json back to object using ObjectMapper. Thanks for your help.

Answer 1

Try org.apache.logging.log4j.core.parser.JsonLogEventParser

JSONObject jobj = new JSONObject(jsonString);
LogEvent logEvent = new JsonLogEventParser().parseFrom(jsonString);

I have a problem to parse some custom LogEvent message then I use JSONLayout with setObjectMessageAsJsonObject(true) option, but if it's a default LogEvent, this worked for me.