pretty-time-messages.java

package com.scarsz;

import java.util.concurrent.TimeUnit;

public class Main {

    public static void main(String[] args) {
        long millis = TimeUnit.MINUTES.toMillis(37) + TimeUnit.SECONDS.toMillis(19);
        String message = getDurationBreakdown(millis);
        System.out.println(message);
    }

    private static String getDurationBreakdown(long millis)
    {
        if (millis < 0) throw new IllegalArgumentException("Duration must be greater than zero!");

        long days = TimeUnit.MILLISECONDS.toDays(millis);
        millis -= TimeUnit.DAYS.toMillis(days);
        long hours = TimeUnit.MILLISECONDS.toHours(millis);
        millis -= TimeUnit.HOURS.toMillis(hours);
        long minutes = TimeUnit.MILLISECONDS.toMinutes(millis);
        millis -= TimeUnit.MINUTES.toMillis(minutes);
        long seconds = TimeUnit.MILLISECONDS.toSeconds(millis);

        StringBuilder sb = new StringBuilder(64);
        if (days > 0) sb.append(days + " days ");
        if (hours > 0) sb.append(hours + " hours ");
        if (minutes > 0) sb.append(minutes + " minutes ");
        if (seconds > 0) sb.append(seconds + " seconds");
        return(sb.toString());
    }
}