DurationFormatPattern.java

import net.time4j.Duration;
import net.time4j.ClockUnit;

import java.text.ParseException;
import java.time.LocalTime;
import java.time.temporal.TemporalAmount;

public class DurationFormatPattern {
  public static void main(String... args) throws ParseException {	
    String input = "5.2345";	
    
    // parse your input	(unknown count of digits for second part, we assume maximum of 6)
    Duration.Formatter<ClockUnit> parser = Duration.formatter(ClockUnit.class, "#####s.ffff");	
    Duration<ClockUnit> duration = parser.parse(input);	
    
    // format your duration object (using two-digit-components for hour, minute etc)
    Duration.Formatter<ClockUnit> printer = Duration.formatter(ClockUnit.class, "hh:mm:ss.ffff");	
    System.out.println("ISO-8601: " + duration); // PT5,234500000S	
    System.out.println(printer.format(duration)); // 00:00:05.2345	
    
    // possible conversions to java.time-type	
    TemporalAmount threeten = duration.toTemporalAmount();	
    System.out.println(LocalTime.MIDNIGHT.plus(threeten)); // 00:00:05.234500
    
  }
}