JPA Define custom error message to multiple columns unique constraint violation

Question

I've a JPA Entity which has a unique constraint based on multiple columns, I'm trying to handle and generate a human friendly error message but somehow spring/hibernate is stealing the exception from me

@Entity
@Table(name = "columns", uniqueConstraints = {@UniqueConstraint(columnNames = {"position", "board_id"}, name = UNIQUE_COLUMN_BOARD_POSITION)})
public class Column {
//some stuff
}

Then i have the service class

   @Transactional
       @NonNull
       public Column update(long columnId, @NonNull Column transientColumn) {


      Column persistentColumn = get(columnId);
      persistentColumn.setTitle(transientColumn.getTitle());
      persistentColumn.setPosition(transientColumn.getPosition());

      try {
         return columnRepository.save(persistentColumn);
      } catch (Exception e) {
         System.out.println(e); //NEVER REACHES HERE
      }

      return transientColumn;
   }

I'm writing my test clases so I autowired the service class, I intentionaly try to update a column to break the unique contraint, hibernate stops the update throw a giant exception... BUT WONT LET ME CAPTURE THE EXCEPTION

I've debugged line by line, the code reaches the save line, then spring/hibernate code starts to run, after that the exception is thrown but my catch clause never gets it and the test finishes

here is the test class

 @Test
   void testFailUpdateDueRepeatedPosition() {

      Column column = new Column(persistentBoard, "column", 1);
      Column column2 = new Column(persistentBoard, "column", 2);

      column = columnRepository.save(column);
      column2 = columnRepository.save(column2);


      column2.setPosition(1);
      columnService.update(column2.getId(), column2);


      columnRepository.delete(column);
   }

I don't care if I can't catch this exception all i want is to have a custom message which i can set in case it happens