JsonbConfig for JAX-RS

[jsonbrobot]

I'm developing Java EE 8 app using JAX-RS.
I have LocalDateTime fields in my Entities.
When I return those entities from JAX-RS resource methods, I indicate desired formatting with @JsonbDateFormat annotation.
Is it possible to define my formatting somewhere once, so it's applied to all entities?

[jsonbrobot]

• Issue Imported From: https://github.com/javaee/jsonb-spec/issues/75
• Original Issue Raised By:@vanuatoo
• Original Issue Assigned To: Unassigned

[kret11]

Create LocalDateTime adapter and use it in your own ContextResolver

[kret11]

import javax.json.bind.Jsonb;
import javax.json.bind.JsonbBuilder;
import javax.ws.rs.ext.ContextResolver;
import javax.ws.rs.ext.Provider;

@Provider
public class JsonbConfig implements ContextResolver<Jsonb> {

  private static Jsonb instance;

  public static Jsonb getInstance() {
    if (instance == null) {
      javax.json.bind.JsonbConfig config = new javax.json.bind.JsonbConfig()
          .withDateFormat("yyyy-MM-dd'T'HH:mmXXX", null).withAdapters(new LocalTimeCustomAdapter());
      instance = JsonbBuilder.create(config);
    }
    return instance;
  }

  @Override
  public Jsonb getContext(Class<?> type) {
    return getInstance();
  }

}

import java.time.LocalTime;
import java.time.format.DateTimeFormatter;
import javax.json.bind.adapter.JsonbAdapter;

public class LocalTimeCustomAdapter implements JsonbAdapter<LocalTime, String> {

  private final static DateTimeFormatter TIME_FORMATTER = DateTimeFormatter.ofPattern("HH:mm");

  @Override
  public String adaptToJson(LocalTime obj) throws Exception {
    return TIME_FORMATTER.format(obj);
  }

  @Override
  public LocalTime adaptFromJson(String obj) throws Exception {
    return LocalTime.parse(obj, TIME_FORMATTER);
  }

}