4

I have two Spring Boot applications which communicate through JMS Messaging and ActiveMQ.

One app sends to the other app an object which contains a LocalDateTime property. This object is serialized to JSON in order to be sent to the other application.

The problem I'm facing is that Jackson is not able to deserialize the LocalDateTime property when it's trying to map the incoming json to my object. The LocalDateTime property has the following format when it arrives to the "listener app":

"lastSeen":{ "nano":0, "year":2019, "monthValue":4, "dayOfMonth":8, "hour":15, "minute":6, "second":0, "month":"APRIL", "dayOfWeek":"MONDAY", "dayOfYear":98, "chronology":{ "id":"ISO", "calendarType":"iso8601" } }

The exception I'm getting is the following:

org.springframework.jms.support.converter.MessageConversionException: Failed to convert JSON message content; nested exception is com.fasterxml.jackson.databind.exc.InvalidDefinitionException: Cannot construct instance of java.time.LocalDateTime

I was able to fix this issue temporarily by using the following annotations:

@JsonSerialize(as = LocalDateTimeSerializer.class) @JsonDeserialize(using = LocalDateTimeDeserializer.class, as = LocalDateTime.class) private LocalDateTime lastSeen;

but they belong to jackson datatype jsr310 which is now DEPRECATED.

Is there any way/alternative to deserialize this LocalDateTime property without using the above annotations? Or how do I get this to work using the recommended jackson-modules-java8?

Improve this question
2
  • 2
    Are you developing both applications? The serialized date looks like a set of calculated fields and it shouldn't be sent like that. There's a lot of redundancy and it cannot be reliably parsed. For serialization, use milliseconds or ISO-8601 string. Commented Feb 11, 2019 at 17:15
  • 2
    jackson datatype jsr310 has been replaced by jackson-modules-java8. Enjoy. Commented Feb 11, 2019 at 17:26

2 Answers 2

Reset to default
7

I remember I did not have this problem with older versions of spring (or maybe I was LUCKY) But this is how I solved it in Spring boot 2.1.7.RELEASE:

First, add Jackson's support modules in order to support Java 8 features (TimeDate API)

 <dependency> <groupId>com.fasterxml.jackson.module</groupId> <artifactId>jackson-module-parameter-names</artifactId> </dependency> <dependency> <groupId>com.fasterxml.jackson.datatype</groupId> <artifactId>jackson-datatype-jdk8</artifactId> </dependency> <dependency> <groupId>com.fasterxml.jackson.datatype</groupId> <artifactId>jackson-datatype-jsr310</artifactId> </dependency>

Then register a default ObjectMapper bean with custom configurations (to support Java 8) in the Spring.

@Bean @Primary public ObjectMapper geObjMapper(){ return new ObjectMapper() .registerModule(new ParameterNamesModule()) .registerModule(new Jdk8Module()) .registerModule(new JavaTimeModule()); }

NOTE: @Primary is used as a precautionary measure, so if there are other ObjectsMapper beans on the class-path, the spring will pick this one by default.

Improve this answer
Sign up to request clarification or add additional context in comments.

1 Comment

In addition to this correct answer note also, you can have the modules auto-discovered as suppose to manually register them. eg: new ObjectMapper().findAndRegisterModules(); That said, you should not really mix manual and auto registration if you do, only one of the registrations will have effect. Source: FasterXML jackson-modules-java8
1

The solution you wrote is right approach. Other approaches are mentioned below. public class LocalDateTimeSerializer implements JsonSerializer { @Override public JsonElement serialize(LocalDateTime localDateTime, Type type, JsonSerializationContext jsonSerializationContext) { Instant instant = localDateTime.atZone(ZoneId.systemDefault()).toInstant(); Date date = Date.from(instant); return new JsonPrimitive(date.getTime()); } }

GsonBuilder gsonBuilder = new GsonBuilder(); gsonBuilder.registerTypeAdapter(LocalDateTime.class, new LocalDateTimeSerializer()); Gson gson = gsonBuilder.create();

Another approach. Any way try this . try to change date time format to string. "2011-04-08T09:00:00". The nano and other format are so complex I cannot tell from your lastseen json what datetime exactly you are talking about. It misses Time zone too so your local time can be anywhere you deploy solution,If you deploy in 3 different time zone machines local time is not correct. Use this string format or make your own "2011-04-08T09:00:00"

public class CustomJsonDateDeserializer extends JsonDeserializer<Date> { @Override public Date deserialize(JsonParser jsonParser, DeserializationContext deserializationContext) throws IOException, JsonProcessingException { SimpleDateFormat format = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss"); String date = jsonParser.getText(); try { return format.parse(date); } catch (ParseException e) { throw new RuntimeException(e); } } } @JsonDeserialize(using = CustomJsonDateDeserializer.class)
Improve this answer

Comments

Start asking to get answers

Find the answer to your question by asking.

Ask question

Explore related questions

See similar questions with these tags.