The challenge

Write a function minutesToMidnight(d) that will take a date object as the parameter. Return the number of minutes in the following format:

“x minute(s)”

You will always get a date object with of today with a random timestamp.
You have to round the number of minutes.
Milliseconds don’t matter!Some examples: 10.00 am => "840 minutes" 23.59 pm => "1 minute"

The solution in Java code

Option 1:

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import java.util.Date;

public class Minute {
  public String countMinutes(Date d){
     int mins=(24-d.getHours()-1)*60+60-d.getMinutes();
     if (d.getHours()==23 && d.getMinutes()==59) return "1 minute";
     return (d.getSeconds()!=0)?  ""+(mins-1)+" minutes" : ""+mins+" minutes";
  }
}

Option 2:

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import static java.time.ZoneOffset.UTC;
import static java.time.temporal.ChronoField.MINUTE_OF_DAY;
import java.util.Date;

class Minute {
  static String countMinutes(Date d) {
    var time = d.toInstant().atZone(UTC);
    int min = 1440 - time.get(MINUTE_OF_DAY) - Math.min(time.getSecond(), 1);
    return min + " minute" + (min == 1 ? "" : "s");
  }
}

Option 3:

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import java.util.Date;
import java.time.LocalDateTime;
import java.time.temporal.ChronoUnit;
import java.time.ZoneId;

public class Minute {
  public String countMinutes(Date d){
        LocalDateTime today = LocalDateTime.ofInstant(d.toInstant(), ZoneId.systemDefault());
        LocalDateTime midnight = today.plusDays(1)
                .withHour(0)
                .withMinute(0)
                .withSecond(0)
                .withNano(0);
        long minutesBetween = ChronoUnit.MINUTES.between(today, midnight);
        return minutesBetween > 1 ? minutesBetween + " minutes" : minutesBetween + " minute";
  }
}

Test cases to validate our solution

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import org.junit.Test;
import static org.junit.Assert.assertEquals;
import org.junit.runners.JUnit4;
import java.util.Date;
import java.util.Random;
import java.util.Calendar;
import java.util.GregorianCalendar;

public class MinuteTest {
    @Test
    public void exampleTests(){
      Minute m = new Minute();
      Calendar cal = new GregorianCalendar();
      cal.set(Calendar.HOUR_OF_DAY, 12);
      cal.set(Calendar.MINUTE, 0);
      cal.set(Calendar.SECOND, 0);
      cal.set(Calendar.MILLISECOND, 0);
      Date d = cal.getTime();
      assertEquals("720 minutes", m.countMinutes(d));
      
      cal.set(Calendar.HOUR_OF_DAY, 23);
      cal.set(Calendar.MINUTE, 59);
      cal.set(Calendar.SECOND, 0);
      cal.set(Calendar.MILLISECOND, 0);
      d = cal.getTime();
      assertEquals("1 minute", m.countMinutes(d));
    }
}