title: Spring Data: JPA repository findAll() to return *Map instead of List?
body: <p>I have a Spring Data JPA repository interface that looks something like this:</p>
  
  <pre><code>@Repository
  public interface DBReportRepository extends JpaRepository&lt;TransactionModel, Long&gt; {
  
      List&lt;TransactionModel&gt; findAll();
      List&lt;TransactionModel&gt; findByClientId(Long id);
  }
  </code></pre>
  
  <p>Is there a workaround to make the same but for a Collection to be returned of type <code>HashMap&lt;K, V&gt;</code>? I've looked through the Spring Data classes and couldn't find anything other than List&lt;> return values. </p>