计算保留两位小数
/**
* 保留两位小数
* 分子可以是小数、整数
* @param a
* @param b
* @return
*/
public String percent(double a ,int b){
if (b == 0) {
return "0.00";
}
// 创建一个数值格式化对象
NumberFormat numberFormat = NumberFormat.getInstance();
//精确到小数点后两位
numberFormat.setMaximumFractionDigits(2);
String result = numberFormat.format((float) a / (float) b);
return result;
}
将秒转换成时分秒(00:00:00)格式
/**
* 将秒转换成时分秒格式
* @param time
* @return
*/
public static String secondSwitchForHMS(Long time) {
String timeStr = null;
Long hour = 0L;
Long minute = 0L;
Long second = 0L;
if (time <= 0)
return "00:00:00";
else {
minute = time / 60;
if (minute < 60) {
second = time % 60;
timeStr = unitFormat(0L)+":"+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;
}