DateResource.java

package com.fun.myapp;

import javax.ws.rs.BeanParam;
import javax.ws.rs.Consumes;
import javax.ws.rs.GET;
import javax.ws.rs.Path;
import javax.ws.rs.Produces;
import javax.ws.rs.QueryParam;
import javax.ws.rs.core.MediaType;
import javax.ws.rs.core.Response;

@Path("/date")
@Produces(MediaType.APPLICATION_JSON)
@Consumes(MediaType.APPLICATION_JSON)
public class DateResource {

    public DateResource() {
        // empty constructor
    }

    @GET
    public Response isValidDate(@QueryParam("date") LocalDateTimeParam date) {
        return Response.ok().build();
    }

    @GET
    @Path("/bean")
    public Response isValidDate(@BeanParam PaginationFilters filter) {
        return Response.ok().build();
    }
}

LocalDateTimeParam.java

package com.fun.myapp;

import io.dropwizard.jersey.params.AbstractParam;

import java.time.LocalDate;
import java.time.LocalDateTime;
import java.time.LocalTime;

import javax.ws.rs.core.MediaType;
import javax.ws.rs.core.Response;
import javax.ws.rs.core.Response.Status;

/**
 * Converts ISO_LOCAL_DATE to {@code LocalDateTime}
 *
 */
public class LocalDateTimeParam extends AbstractParam<LocalDateTime> {

    public LocalDateTimeParam(String input) {
        super(input);
    }

    @Override
    protected LocalDateTime parse(String input) throws Exception {
        return LocalDateTime.of(LocalDate.parse(input), LocalTime.MIDNIGHT);
    }

    @Override
    protected Response error(String input, Exception e) {
        return Response
                .status(Status.BAD_REQUEST)
                .type(MediaType.APPLICATION_JSON_TYPE)
                .entity("Date is either not in YYYY-MM-DD format or is invalid")
                .build();
    }

}

MultiExceptionMapper.java

package com.fun.myapp;

import org.glassfish.hk2.api.MultiException;

import javax.ws.rs.WebApplicationException;
import javax.ws.rs.core.MediaType;
import javax.ws.rs.core.Response;
import javax.ws.rs.ext.ExceptionMapper;

public class MultiExceptionMapper implements ExceptionMapper<MultiException> {

    @Override
    public Response toResponse(MultiException exception) {
        for (Throwable ex : exception.getErrors()) {
            if (WebApplicationException.class.isAssignableFrom(ex.getClass())) {
                return ((WebApplicationException) ex).getResponse();
            }
        }
        return Response
                .serverError()
                .entity("Internal Error occurred.")
                .type(MediaType.APPLICATION_JSON_TYPE)
                .build();
    }
}

MyApp.java

package com.fun.myapp;

import io.dropwizard.Application;
import io.dropwizard.setup.Environment;

public class MyApp extends Application<MyAppConfig> {

    @Override
    public void run(MyAppConfig configuration, Environment environment) throws Exception {
        environment.jersey().register(DateResource.class);
        // adding the following exception mapper handles MultiException well. i.e. produces error
        // indicated by *Param class
        // environment.jersey().register(MultiExceptionMapper.class);
    }

    public static void main(String[] args) throws Exception {
        new MyApp().run(args);
    }

}

MyAppConfig.java

package com.fun.myapp;

import io.dropwizard.Configuration;

public class MyAppConfig extends Configuration {

    public MyAppConfig() {
        // TODO Auto-generated constructor stub
    }

}

PaginationFilters.java

package com.fun.myapp;

import java.time.LocalDateTime;
import java.util.Optional;

import javax.validation.constraints.NotNull;
import javax.ws.rs.QueryParam;

public class PaginationFilters {

    public PaginationFilters() {
        // empty constructor
    }

    @NotNull(message = "date must be specified")
    @QueryParam("date")
    private LocalDateTimeParam date;

    public Optional<LocalDateTime> getDate() {
        if (date != null) {
            return Optional.of(date.get());
        }
        else {
            return Optional.empty();
        }
    }
}