public String anonymize(final ParseTree tree) {
    return build(tree);
  }
@Test
  public void shouldAnonymizeJoinWithGraceStatementsCorrectly() {
    final String output = anon.anonymize("INSERT INTO OUTPUT SELECT col1, col2, col3"
        + " FROM SOURCE1 S1 JOIN SOURCE2 S2 "
        + "WITHIN 1 SECOND GRACE PERIOD 2 SECONDS ON col1.k=col2.k;");

    Approvals.verify(output);
  }