This and that of the implementation of date judgment within the period in Java

What is this?

A page that considers the implementation of determining the date range (Between) in Java

Theme

I want to determine whether a date is included or not included for a given two periods (dates). For example, for July 20th to July 30th, "August 1st is not included" and "July 20th, July 25th, July 30th" are included. If you compare it with a line ...

---●---------------------●------
   7/20                 7/30

● will mean that the day is included.

How to implement

Part 1

boolean between(LocalDate date){
  return (startDate.isBefore(date) && endDate.isAfter(date)) || startDate.equals(date) || endDate.equals(date);
}

Part 2 (smarter)

boolean between(LocalDate date){
  return !(startDate.isAfter(date) || endDate.isBefore(date));
}

Extra edition

---○---------------------○------
   7/20                 7/30

○ means that the day is not included.

Part 1

boolean between(LocalDate date){
  return (startDate.isBefore(date) && endDate.isAfter(date));
}

boolean between(LocalDate date){
  //It shouldn't be based on external values, but it's simple
  return date.isAfter(startDate) && date.isBefore(endDate);
}

Part 2 (smarter?)

boolean between(LocalDate date){
  return startDate.compareTo(date) * endDate.compareTo(date) < 0;
}

boolean between(LocalDate date){
  // //It should not be based on external values, but as a pattern
  return startDate.compareTo(date) * date.compareTo(endDate) > 0;
}

If you want to follow the original theme (make it ●), you can give it as ```> introduced or <introduced.

Impressions

The theme that the cleverness comes out in Moro. I want to be myself who can implement smartly.
However, there is a trade-off in that readability is reduced. (Since it is not an intuitive implementation, it puts the reader in a "?" State)
It may be a standard program in a sense. I feel that the same can be said for so-called "hit judgment" logic such as java.awt.Rectangle # intersects` `` and` `java.awt.Rectangle # intersection.

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