Java中整数(秒数)转换为时分秒格式(xx:xx:xx)

// a integer to xx:xx:xx
public static String secToTime(int time) {
String timeStr = null;
int hour = 0;
int minute = 0;
int second = 0;
if (time <= 0)
return "00:00";
else {
minute = time / 60;
if (minute < 60) {
second = time % 60;
timeStr = unitFormat(minute) + ":" + unitFormat(second);
} else {
hour = minute / 60;
if (hour > 99)
return "99:59:59";
minute = minute % 60;
second = time - hour * 3600 - minute * 60;
timeStr = unitFormat(hour) + ":" + unitFormat(minute) + ":" + unitFormat(second);
}
}
return timeStr;
}

public static String unitFormat(int i) {
String retStr = null;
if (i >= 0 && i < 10)
retStr = "0" + Integer.toString(i);
else
retStr = "" + i;
return retStr;
}