title: Spring Data JPA and Projection getting ConverterNotFoundException for TupleConverter
body: <p>Is there a way to write and register a <code>TupleConverter</code> converter in Spring Data? I'm getting this exception when I have an @Query annotation in the Repository interface and asking for Projection. </p>
  
  <p>The Interface:</p>
  
  <pre><code>public interface ProjectRepository extends JpaRepository&lt;Project, Integer&gt; {
      @Query("select p.projectId, p.projectName, p.techstack from Project p")
      public List&lt;ProjectItem&gt; findAllForTest();
  }
  </code></pre>
  
  <p>The DTO:</p>
  
  <pre><code>public class ProjectItem {
      private final Integer projectId;
      private final String projectName;
      private final String techstack;
      @JsonCreator
      public ProjectItem(
          @JsonProperty("projectId") Integer projectId, 
          @JsonProperty("projectName") String projectName, 
          @JsonProperty("techstack") String techstack
      ) {
          this.projectId = projectId;
          this.projectName = projectName;
          this.techstack = techstack;
      }
      public Integer getProjectId() {
          return projectId;
      }
      public String getProjectName() {
          return projectName;
      }
      public String getTechstack() {
          return techstack;
      }
  }
  </code></pre>
  
  <p>The exception </p>
  
  <blockquote>
    <blockquote>
      <p>No converter found capable of converting from type [org.springframework.data.jpa.repository.query.AbstractJpaQuery$TupleConverter$TupleBackedMap] to type [project.item.ProjectItem]] with root cause</p>
    </blockquote>
  </blockquote>