/* package whatever; // don't place package name! */
 
import java.util.*;
import java.lang.*;
import java.io.*;
 
import java.time.* ;
 
/* Name of the class has to be "Main" only if the class is public. */
class Ideone
{
	public static void main (String[] args) throws java.lang.Exception
	{
 
    int gapInMinutes =  30 ;  // Define your span-of-time.
    int loops = ( (int) Duration.ofHours( 24 ).toMinutes() / gapInMinutes ) ;
    List<LocalTime> times = new ArrayList<>( loops ) ;
 
    LocalTime time = LocalTime.MIN ;  // '00:00'
    for( int i = 1 ; i <= loops ; i ++ ) {
        times.add( time ) ;
        // Set up next loop.
        time = time.plusMinutes( gapInMinutes ) ;
    }
 
    System.out.println( times.size() + " time slots: " ) ;
    System.out.println( times ) ;
 
	}
}

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