在scala中，不需要库:

def prettyDuration(str:List[String],seconds:Long):List[String]={
  seconds match {
    case t if t < 60 => str:::List(s"${t} seconds")
    case t if (t >= 60 && t< 3600 ) => List(s"${t / 60} minutes"):::prettyDuration(str, t%60)
    case t if (t >= 3600 && t< 3600*24 ) => List(s"${t / 3600} hours"):::prettyDuration(str, t%3600)
    case t if (t>= 3600*24 ) => List(s"${t / (3600*24)} days"):::prettyDuration(str, t%(3600*24))
  }
}
val dur = prettyDuration(List.empty[String], 12345).mkString("")

在scala中，不需要库:

def prettyDuration(str:List[String],seconds:Long):List[String]={
  seconds match {
    case t if t < 60 => str:::List(s"${t} seconds")
    case t if (t >= 60 && t< 3600 ) => List(s"${t / 60} minutes"):::prettyDuration(str, t%60)
    case t if (t >= 3600 && t< 3600*24 ) => List(s"${t / 3600} hours"):::prettyDuration(str, t%3600)
    case t if (t>= 3600*24 ) => List(s"${t / (3600*24)} days"):::prettyDuration(str, t%(3600*24))
  }
}
val dur = prettyDuration(List.empty[String], 12345).mkString("")

从Java 9开始，这变得更容易了。Duration仍然是不可格式化的，但是添加了获取小时、分钟和秒的方法，这使得任务更简单:

    LocalDateTime start = LocalDateTime.of(2019, Month.JANUARY, 17, 15, 24, 12);
    LocalDateTime end = LocalDateTime.of(2019, Month.JANUARY, 18, 15, 43, 33);
    Duration diff = Duration.between(start, end);
    String hms = String.format("%d:%02d:%02d", 
                                diff.toHours(), 
                                diff.toMinutesPart(), 
                                diff.toSecondsPart());
    System.out.println(hms);

这个代码片段的输出是:

24:19:21

我的库Time4J提供了一个基于模式的解决方案(类似于Apache DurationFormatUtils，但更灵活):

Duration<ClockUnit> duration =
    Duration.of(-573421, ClockUnit.SECONDS) // input in seconds only
    .with(Duration.STD_CLOCK_PERIOD); // performs normalization to h:mm:ss-structure
String fs = Duration.formatter(ClockUnit.class, "+##h:mm:ss").format(duration);
System.out.println(fs); // output => -159:17:01

这段代码演示了处理小时溢出和符号处理的功能，请参见基于模式的持续时间格式化程序的API。

下面是另一个如何格式化持续时间的示例。 注意，这个示例将正持续时间和负持续时间都显示为正持续时间。

import static java.time.temporal.ChronoUnit.DAYS;
import static java.time.temporal.ChronoUnit.HOURS;
import static java.time.temporal.ChronoUnit.MINUTES;
import static java.time.temporal.ChronoUnit.SECONDS;

import java.time.Duration;

public class DurationSample {
    public static void main(String[] args) {
        //Let's say duration of 2days 3hours 12minutes and 46seconds
        Duration d = Duration.ZERO.plus(2, DAYS).plus(3, HOURS).plus(12, MINUTES).plus(46, SECONDS);

        //in case of negative duration
        if(d.isNegative()) d = d.negated();

        //format DAYS HOURS MINUTES SECONDS 
        System.out.printf("Total duration is %sdays %shrs %smin %ssec.\n", d.toDays(), d.toHours() % 24, d.toMinutes() % 60, d.getSeconds() % 60);

        //or format HOURS MINUTES SECONDS 
        System.out.printf("Or total duration is %shrs %smin %sec.\n", d.toHours(), d.toMinutes() % 60, d.getSeconds() % 60);

        //or format MINUTES SECONDS 
        System.out.printf("Or total duration is %smin %ssec.\n", d.toMinutes(), d.getSeconds() % 60);

        //or format SECONDS only 
        System.out.printf("Or total duration is %ssec.\n", d.getSeconds());
    }
}

这可能有点俗气，但如果你决心使用Java 8的Java .time来实现这一点，这是一个很好的解决方案:

import java.time.Duration;
import java.time.LocalDateTime;
import java.time.format.DateTimeFormatter;
import java.time.format.DateTimeFormatterBuilder;
import java.time.temporal.ChronoField;
import java.time.temporal.Temporal;
import java.time.temporal.TemporalAccessor;
import java.time.temporal.TemporalField;
import java.time.temporal.UnsupportedTemporalTypeException;

public class TemporalDuration implements TemporalAccessor {
    private static final Temporal BASE_TEMPORAL = LocalDateTime.of(0, 1, 1, 0, 0);

    private final Duration duration;
    private final Temporal temporal;

    public TemporalDuration(Duration duration) {
        this.duration = duration;
        this.temporal = duration.addTo(BASE_TEMPORAL);
    }

    @Override
    public boolean isSupported(TemporalField field) {
        if(!temporal.isSupported(field)) return false;
        long value = temporal.getLong(field)-BASE_TEMPORAL.getLong(field);
        return value!=0L;
    }

    @Override
    public long getLong(TemporalField field) {
        if(!isSupported(field)) throw new UnsupportedTemporalTypeException(new StringBuilder().append(field.toString()).toString());
        return temporal.getLong(field)-BASE_TEMPORAL.getLong(field);
    }

    public Duration getDuration() {
        return duration;
    }

    @Override
    public String toString() {
        return dtf.format(this);
    }

    private static final DateTimeFormatter dtf = new DateTimeFormatterBuilder()
            .optionalStart()//second
            .optionalStart()//minute
            .optionalStart()//hour
            .optionalStart()//day
            .optionalStart()//month
            .optionalStart()//year
            .appendValue(ChronoField.YEAR).appendLiteral(" Years ").optionalEnd()
            .appendValue(ChronoField.MONTH_OF_YEAR).appendLiteral(" Months ").optionalEnd()
            .appendValue(ChronoField.DAY_OF_MONTH).appendLiteral(" Days ").optionalEnd()
            .appendValue(ChronoField.HOUR_OF_DAY).appendLiteral(" Hours ").optionalEnd()
            .appendValue(ChronoField.MINUTE_OF_HOUR).appendLiteral(" Minutes ").optionalEnd()
            .appendValue(ChronoField.SECOND_OF_MINUTE).appendLiteral(" Seconds").optionalEnd()
            .toFormatter();

}