How to return multiple objects from one Java method?

Question

In here I'm trying to return two results as one response and not sure what option may good with it. In here it return as a list,

List<FixedDeposit> fdList = em.createQuery(sb.toString())
            .setParameter("start", dateFrom)
            .setParameter("end", dateTo)
            .setFirstResult(start).setMaxResults(limit)
            .getResultList();

so I have got it as

List<FDSearchResult> searchList = getSearchResult(fdList); 
response.setData(searchList);
return response;

And now again I want to return another response. And this is the calculation,

Double sum = 0.0;
sum = (Double) em.createQuery("SELECT SUM(deposit_amount)FROM fd_fixed_deposit where fd.status in ('ACT','REN','WDR') and fd.maturityDate between :start and :end ")
                .setParameter("start", dateFrom)
                .setParameter("end", dateTo).getSingleResult();

So how can I return the result through response for the sum? Please Help

I will post the full method,

public Response<List<FDSearchResult>> loadMaturedFDByRange(String fromDate, String toDate, final Integer start,
        final Integer limit) {
    final Response<List<FDSearchResult>> response = new Response<List<FDSearchResult>>();
    Date dateFrom = DateUtils.parseDate("dd/MM/yyyy", fromDate, null);
    Date dateTo = DateUtils.parseDate("dd/MM/yyyy", toDate, null);
    Long count = 0L;
    Double sum = 0.0;
    try {
        count = (Long) em.createQuery("SELECT COUNT(fd) FROM FixedDeposit fd where fd.status in ('ACT','REN','WDR') "
                + "and fd.maturityDate between :start and :end ")
                .setParameter("start", dateFrom)
                .setParameter("end", dateTo).getSingleResult();
    } catch (NoResultException nre) {
        count = 0L;
    }
    StringBuilder sb = new StringBuilder();
    sb.append("SELECT fd FROM FixedDeposit fd where fd.status in ('ACT','REN','WDR') and fd.maturityDate between :start and :end ");
    List<FixedDeposit> fdList = em.createQuery(sb.toString())
            .setParameter("start", dateFrom)
            .setParameter("end", dateTo)
            .setFirstResult(start).setMaxResults(limit)
            .getResultList();

    sum = (Double) em.createQuery("SELECT SUM(deposit_amount)FROM fd_fixed_deposit where fd.status in ('ACT','REN','WDR') and fd.maturityDate between :start and :end ")
                .setParameter("start", dateFrom)
                .setParameter("end", dateTo).getSingleResult();

    List<FDSearchResult> searchList = getSearchResult(fdList);
    response.setData(searchList);
    response.setPagination(new Response().new PaginationInfo(count));
    return response;
}

Maybe you are looking for [Arrays](https://docs.oracle.com/javase/7/docs/api/java/util/Arrays.html). — Mistalis, Feb 28 '17 at 10:32
Returning a map could help, so you can organize your objects in it — DamCx, Feb 28 '17 at 10:33
If it's always going to be 2 objects of that type, create another object to store them both and return that. — Steve Smith, Feb 28 '17 at 10:35
Possible duplicate of [How to return multiple objects from a Java method?](http://stackoverflow.com/questions/457629/how-to-return-multiple-objects-from-a-java-method) — SymbolixAU, Apr 13 '17 at 07:42

score 3 · Accepted Answer · answered Feb 28 '17 at 10:35

In this instance, I would create an Object Container that holds these two objects and return that object instead.

public class MyContainer
{
   List<FixedDeposit> fdList;
   List<FDSearchResult> searchList;

   public MyContainer()
   {

   }
}

This is how I would approach this.

score 1 · Answer 2 · answered Feb 28 '17 at 10:34

1

You can return all relevant data via result objects. Just create a new class which can obtain all your needed values.

answered Feb 28 '17 at 10:34

kamehl23

522
3
6

uday · Answer 3 · 2017-02-28T10:46:18.830

0

Two options:

HashMap. Type cast Object to response and Double respectively. This is not a good practice

You can create a custom class which can encapsulate different object types. Generics is what you need here.

public class MultiReturn<T> {
  public final String name;
  public final T object;

  public NamedObject(String name, T object) {
     this.name = name;
     this.object = object;
  }
}

edited Feb 28 '17 at 10:46

answered Feb 28 '17 at 10:39

uday

361
1
11

How to return multiple objects from one Java method?

3 Answers3