custom-objectmapper-provider

/*
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######### IF YOU FOUND THIS GIST USEFUL, PLEASE LEAVE A STAR. THANKS. ############
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*/


public final class JsonUtil {
  public static ObjectMapper getMapper() {
    SimpleModule module = new SimpleModule();
    module.addSerializer(LocalDateTime.class, new JsonSerializer<>() {
      @Override
      public void serialize(LocalDateTime utcDateTime, JsonGenerator jsonGenerator, SerializerProvider serializers) throws IOException {
        String dateTimeWithZone = utcDateTime.atZone(ZoneOffset.UTC).toString();
        jsonGenerator.writeString(dateTimeWithZone);
      }
    });
    ObjectMapper o = new ObjectMapper();
    o.registerModules(module);
    return o;
  }
}

Jackson Custom Serialization Sample1.md

Use Case:

• We are manually serializing the object
• We want to serialize a particular type of field (eg. LocalDateTime type) in a custom way

How am I doing it

• Modifying the ObjectMapper instance to create modules defining serializers for particular type and registering those modules in the ObjectMapper.

object-to-serialize

@JsonSerialize(using = EventSerializer.class)
public class Event {
  private String name;

  private LocalDateTime startDate;

  private LocalDateTime endDate;

  public String getName() {
    return name;
  }

  public void setName(String name) {
    this.name = name;
  }

  public LocalDateTime getStartDate() {
    return startDate;
  }

  public void setStartDate(LocalDateTime startDate) {
    this.startDate = startDate;
  }

  public LocalDateTime getEndDate() {
    return endDate;
  }

  public void setEndDate(LocalDateTime endDate) {
    this.endDate = endDate;
  }
}

usage

Event event = new Event();
event.setName("someEvent");
event.setStartDate(LocalDateTime.now());
event.setEndDate(LocalDateTime.now().plusDays(1));
System.out.println(JsonUtil.getMapper().writeValueAsString(event));