How to set time to 24 hour format in Calendar

Question

I need to set the time on the current date. The time string is always in 24 hour format but the result I get is wrong:

  SimpleDateFormat df = new SimpleDate         


        

Answer 1

if you replace in the function SimpleDateFormat("hh") with ("HH") will format the hour in 24 hours instead of 12.

SimpleDateFormat df = new SimpleDateFormat("HH:mm");

Answer 2

Try this :

SimpleDateFormat df = new SimpleDateFormat("hh:mm");

Or

SimpleDateFormat df = new SimpleDateFormat("KK:mm");

Reference : SimpleDateFormat

Answer 3

private void setClock() {

    Timeline clock = new Timeline(new KeyFrame(Duration.ZERO, e -> {
        Calendar cal = Calendar.getInstance();
        int second = cal.get(Calendar.SECOND);
        int minute = cal.get(Calendar.MINUTE);
        int  hour = cal.get(Calendar.HOUR_OF_DAY);
        eski_minut = minute;
        if(second < 10){

            time_label.setText(hour + ":" + (minute) + ":0" + second);

        }else if (minute < 10){
            time_label.setText(hour + ":0" + (minute) + ":0" + second);

        }
        else {
        time_label.setText(hour + ":" + (minute) + ":" + second);}
    }),
            new KeyFrame(Duration.seconds(1))
    );
    clock.setCycleCount(Animation.INDEFINITE);
    clock.play();
}

Answer 4

Replace this:

c1.set(Calendar.HOUR, d1.getHours());

with this:

c1.set(Calendar.HOUR_OF_DAY, d1.getHours());

Calendar.HOUR is strictly for 12 hours.

Answer 5

I am using fullcalendar on my project recently, I don't know what exact view effect you want to achieve, in my project I want to change the event time view from 12h format from

to 24h format.

If this is the effect you want to achieve, the solution below might help:

set timeFormat: 'H:mm'

Answer 6

tl;dr

LocalTime.parse( "10:30" )  // Parsed as 24-hour time.

java.time

Avoid the troublesome old date-time classes such as Date and Calendar that are now supplanted by the java.time classes.

LocalTime

The java.time classes provide a way to represent the time-of-day without a date and without a time zone: LocalTime

LocalTime lt = LocalTime.of( 10 , 30 );  // 10:30 AM.
LocalTime lt = LocalTime.of( 22 , 30 );  // 22:30 is 10:30 PM.

ISO 8601

The java.time classes use standard ISO 8601 formats by default when generating and parsing strings. These formats use 24-hour time.

String output = lt.toString();

LocalTime.of( 10 , 30 ).toString() : 10:30

LocalTime.of( 22 , 30 ).toString() : 22:30

So parsing 10:30 will be interpreted as 10:30 AM.

LocalTime lt = LocalTime.parse( "10:30" );  // 10:30 AM.

DateTimeFormatter

If you need to generate or parse strings in 12-hour click format with AM/PM, use the DateTimeFormatter class. Tip: make a habit of specifying a Locale.