獲得當前系統日期 星期幾、小時

public static void main(String[] args) {
	Date date=new Date();
	Calendar cal = Calendar.getInstance();
	cal.setTime(date);
	int w = cal.get(Calendar.DAY_OF_WEEK) - 1;
	int h = cal.get(Calendar.HOUR_OF_DAY);
	System.err.println(w);
	System.err.println(h);
	Date d = new Date();
	System.err.println("d.getHours()===="+d.getHours());
}
 

信用卡有效日期校驗

/****
 * boolean result=checkBankEffectiveData("0917");
 * 信用卡有效日期校驗
 * @param effectiveData
 * @return
 */
private static boolean checkBankEffectiveData(String effectiveData) throws Exception {
	String month=effectiveData.substring(0,2);
	String year=effectiveData.substring(2,4);
	effectiveData="20"+year+"-"+month+"-01";
	String pattern = "yyyy-MM-dd";
	SimpleDateFormat dateFormat = new SimpleDateFormat(pattern);
	Date bankEffectiveData = dateFormat.parse(effectiveData);
	Date nowdate = new Date();
	Calendar c1 = Calendar.getInstance();
	Calendar c2 = Calendar.getInstance();
	c1.setTime(bankEffectiveData);
	c2.setTime(nowdate);
	int result = c1.compareTo(c2);
	if (result >= 0)
		return true;
	else
		return false;
}
 

/***
 * 兩個日期相差多少分鐘
 * @param beginTime beginTime<endTime
 * @param endTime
 * @return
 */
public static Long differenceTime(Date beginTime, Date endTime) {

	long begintime = beginTime.getTime();
	long endtime = endTime.getTime();
	long diff;
	long diffTime;
	if (begintime < endtime) {
		diff = endtime - begintime;
	} else {
		diff = begintime-endtime;
	}
//	diffTime = diff / (60 * 60 * 1000);
//	System.err.println("相差" + diffTime + "小時");
	diffTime = diff / (60 * 1000);
	System.err.println("相差" + diffTime + "分鐘");
	return diffTime;
}
 

        Calendar c = Calendar.getInstance(TimeZone.getTimeZone("GMT+08:00"));    //獲取東八區時間
        int year = c.get(Calendar.YEAR);                //獲取年
        int month = c.get(Calendar.MONTH) + 1;          //獲取月份，0表示1月份
        int day = c.get(Calendar.DAY_OF_MONTH);         //獲取當前天數
        int first = c.getActualMinimum(c.DAY_OF_MONTH); //獲取本月最小天數
        int last = c.getActualMaximum(c.DAY_OF_MONTH);  //獲取本月最大天數
        int time = c.get(Calendar.HOUR_OF_DAY);         //獲取當前小時
        int min = c.get(Calendar.MINUTE);               //獲取當前分鐘
        int xx = c.get(Calendar.SECOND);                //獲取當前秒

        SimpleDateFormat s=new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
        String curDate = s.format(c.getTime());  //當前日期
        System.err.println("當前時間："+year + "-" + month + "-"+ day + " "+time + ":" + min +":" + xx);
        System.err.println("第一天和最後天：" + first +"," + last);
        System.err.println("當前日期curDate====：" + curDate);
//      當前時間：2017-8-24 12:37:17
//      第一天和最後天：1,31
//      當前日期curDate====：2017-08-24 12:37:17

日期校驗

private static final long SEVEN_DAYS=1000*60*60*24*7;
private static final long ONE_DAYS=1000*60*60*24;
private static final long ONE_HOUR=1000*60*60;
private static final int MAX_COUNTLIMIT = 5000;

/****
* 日期校驗
* @param currDate
* @param beginDate
* @param endDate
* @return
*/
private boolean dateValidate(Date currDate, Date beginDate,Date endDate) {
	long currLong = currDate.getTime();//當前時間
	long beginLong = beginDate.getTime();//開始時間
	long endLong =endDate.getTime();//結束時間

	long diffBegin=currLong-beginLong;
	long diffEnd=currLong-endLong;
	long diffBeginEnd = endLong-beginLong;//判斷日期時候合法>0
	
	if(diffBegin<0||diffEnd<0||diffBeginEnd<0){
		System.err.println("日期非法");
		return false;
	}	
	if (diffBegin > SEVEN_DAYS || diffEnd > SEVEN_DAYS) {
		System.err.println("時間範圍大於7日");
		return false;
	}
	return true;
}