Java如何仅使用小时，分钟和秒来比较LocalTime

Question

I want to compare if 2 LocalTime are equal, but only using the hours, minutes and seconds, not with all the data of the variable, like milliseconds.

How can I accomplish that?

Answer 1

You can set the hours to the same in both with myTime.withHour(0) , than you have left only the minutes and seconds that differ and you are able to come these 2 times.

Example:

time1 = ...
time2 = ...

if (time1.withHour(0).equals(time2.withHour(0))) {
  System.out.println('Minutes and Seconds of time1 and time2 are equal!');
}

Answer 2

You can just set both nanos to one number to make them the same with each other, say, zero, to compare them.

LocalTime localTime1 = LocalTime.of(1, 2, 3, 100);
LocalTime localTime2 = LocalTime.of(1, 2, 3, 47);
if (localTime1.withNano(0).equals(localTime2.withNano(0))){
    System.out.println("something");
}

Answer 3

Considering the last edited version of your question, you can compare two instances of LocalTime by just hour, minute and second part this way:

LocalTime lt1 = LocalTime.now(); // usually contains seconds and subseconds
LocalTime lt2 = LocalTime.of(22, 48); // example with zero second part

boolean isEqualInSecondPrecision = 
    lt1.truncatedTo(ChronoUnit.SECONDS).equals(lt2.truncatedTo(ChronoUnit.SECONDS));

Answer 4

Something like this

LocalTime t1=..
LocalTime t2=..
LocalTime.of(t1.getHour(), t1.getMinutes()).compareTo(LocalTime.of(t2.getHour(),t2.getMinutes());

with also seconds if u need of course