### Question:
H2OpenJpaDialect extends OpenJpaDialect { @Override public DataAccessException translateExceptionIfPossible(RuntimeException re) { DataAccessException e = null; if (ExceptionUtils.getRootCause(re) instanceof JdbcSQLException) { JdbcSQLException rootException = (JdbcSQLException)ExceptionUtils.getRootCause(re); switch(rootException.getErrorCode()) { case ErrorCode.DUPLICATE_KEY_1: { e = new DuplicateItemException("DUPLICATE_ITEM", rootException); break; } default: { e = new TranslatedH2Exception(rootException.getErrorCode(), "ERROR", "Unknown Database Error"); break; } } } else { e = new TranslatedH2Exception(TranslatedH2Exception.UNKNOWN_ERROR_CODE, "ERROR", "Unknown Runtime Exception"); } return e; }  @Override DataAccessException translateExceptionIfPossible(RuntimeException re);  }### Answer:
@Test public void testTranslateExceptionIfPossible_uniqueContstraintViolation() { JdbcSQLException jdbcEx = new JdbcSQLException("message", "sql statement", "state", ErrorCode.DUPLICATE_KEY_1, null, "stacktrace"); RuntimeException re = new RuntimeException("dummy runtime exception", jdbcEx); assertTrue(dialect.translateExceptionIfPossible(re) instanceof DuplicateItemException); }
@Test public void testTranslateExceptionIfPossible_unknownJdbcSQLExceptionError() { JdbcSQLException jdbcEx = new JdbcSQLException("message", "sql statement", "state", ErrorCode.CANNOT_DROP_CURRENT_USER, null, "stacktrace"); RuntimeException re = new RuntimeException("dummy runtime exception", jdbcEx); TranslatedH2Exception translatedException = (TranslatedH2Exception) dialect.translateExceptionIfPossible(re); assertThat(translatedException.getErrorCode(), is(ErrorCode.CANNOT_DROP_CURRENT_USER)); }
@Test public void testTranslateExceptionIfPossible_unknownRuntimeError() { RuntimeException re = new RuntimeException("dummy runtime exception", new NullPointerException("bad")); TranslatedH2Exception translatedException = (TranslatedH2Exception) dialect.translateExceptionIfPossible(re); assertThat(translatedException.getErrorCode(), is(TranslatedH2Exception.UNKNOWN_ERROR_CODE)); }