public String process(final Expression expression) {
    return formatExpression(expression);
  }
@Test
  public void shouldThrowOnTimeDateNEQ() {
    // Given:
    final ComparisonExpression compExp = new ComparisonExpression(
        Type.NOT_EQUAL,
        TIMECOL,
        DATECOL
    );

    // Then:
    final Exception e = assertThrows(KsqlException.class, () -> sqlToJavaVisitor.process(compExp));
    assertThat(e.getMessage(), is("Unexpected comparison to TIME: DATE"));
  }