把毫秒转换成日期、天数

把一个毫秒转换成日期

private String timeToString(Long millisecond){
		String str = "";
		SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
		Timestamp ts = new Timestamp(millisecond);
		str = sdf.format(ts);
		return str;
	}

计算X毫秒相当于几天

private String periodToString(Long millisecond){
		String str = "";
		long day = millisecond /  86400000;
		long hour = (millisecond % 86400000) / 3600000 ;
		long minute = (millisecond %  86400000 % 3600000) / 60000;
		if(day > 0){
			str = String.valueOf(day) + "天";
		}
		if(hour > 0){
			str += String.valueOf(hour) + "小时";
		}
		if(minute > 0){
			str += String.valueOf(minute) + "分钟";
		}
		return str;
	}