How to Properly Format Java 8's LocalDate with Jackson?

Using Jackson to Format LocalDate in Java 8

In this article, we'll explore how to format java.time.LocalDate using Jackson in Java 8.

Problem Description

When working with Java 8's LocalDate field, attempting to use the same annotations used for java.util.Date may not yield the desired results.

Failed Attempt

@JsonDeserialize(using = LocalDateDeserializer.class)  
@JsonSerialize(using = LocalDateSerializer.class)  
private LocalDate dateOfBirth;

Solution

To correctly format LocalDate, the following steps should be taken:

1. Add the jackson-datatype-jsr310 dependency:

   <dependency>
       <groupId>com.fasterxml.jackson.datatype</groupId>
       <artifactId>jackson-datatype-jsr310</artifactId>
       <version>2.4.0</version>
   </dependency>

2. Create a ContextResolver for ObjectMapper:

   import com.fasterxml.jackson.databind.ObjectMapper;
   import com.fasterxml.jackson.databind.SerializationFeature;
   import com.fasterxml.jackson.datatype.jsr310.JavaTimeModule;
   import javax.ws.rs.ext.ContextResolver;
   import javax.ws.rs.ext.Provider;
   
   @Provider
   public class ObjectMapperContextResolver implements ContextResolver<ObjectMapper> {  
       private final ObjectMapper MAPPER;
   
       public ObjectMapperContextResolver() {
           MAPPER = new ObjectMapper();
           MAPPER.registerModule(new JavaTimeModule());
           MAPPER.configure(SerializationFeature.WRITE_DATES_AS_TIMESTAMPS, false);
       }
   
       @Override
       public ObjectMapper getContext(Class<?> type) {
           return MAPPER;
       }  
   }

3. Register the ObjectMapperContextResolver in the resource class:

   @Path("person")
   public class LocalDateResource {
   
       @GET
       @Produces(MediaType.APPLICATION_JSON)
       public Response getPerson() {
           Person person = new Person();
           person.birthDate = LocalDate.now();
           return Response.ok(person).build();
       }
   
       @POST
       @Consumes(MediaType.APPLICATION_JSON)
       public Response createPerson(Person person) {
           return Response.ok(
                   DateTimeFormatter.ISO_DATE.format(person.birthDate)).build();
       }
   
       public static class Person {
           public LocalDate birthDate;
       }
   }

Testing

You can now test the formatting by issuing the following HTTP requests:

# Get person
curl -v http://localhost:8080/api/person

# Create person
curl -v -POST -H "Content-Type:application/json" -d "{\"birthDate\":\"2015-03-01\"}" http://localhost:8080/api/person

Expected Response:

{"birthDate":"2015-03-01"}

2015-03-01

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