OldKeyword { public static Builder builder() { return new Builder(); } private  OldKeyword(Optional<Boolean> isUnread, Optional<Boolean> isFlagged, Optional<Boolean> isAnswered,
                      Optional<Boolean> isDraft, Optional<Boolean> isForwarded); static Builder builder(); Optional<Boolean> isUnread(); Optional<Boolean> isFlagged(); Optional<Boolean> isAnswered(); Optional<Boolean> isDraft(); Optional<Boolean> isForwarded(); Flags applyToState(Flags currentFlags); Keywords asKeywords(); @Override final boolean equals(Object other); @Override final int hashCode(); @Override String toString();  }
@Test public void computeOldKeywordsShouldReturnEmptyWhenAllEmpty() { Optional<OldKeyword> testee = OldKeyword.builder() .computeOldKeyword(); assertThat(testee).isEmpty(); }