examcloud-components/src/main/java/cn/com/qmth/examcloud/commons/util/DateUtil.java

package cn.com.qmth.examcloud.commons.util;

import java.math.BigDecimal;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Calendar;
import java.util.Date;

import cn.com.qmth.examcloud.commons.exception.ExamCloudRuntimeException;

/**
 * 日期工具
 * 
 * @author WANGWEI
 */
public class DateUtil {

	/**
	 * patterns describing the date and time format
	 *
	 * @author WANGWEI
	 */
	public interface DatePatterns {

		public static final String DEFAULT = "yyyyMMddHHmmss";

		public static final String YYYY = "yyyy";

		public static final String YYYYMM = "yyyyMM";

		public static final String YYYYMMDD = "yyyyMMdd";

		public static final String YYYYMMDDHH = "yyyyMMddHH";

		public static final String YYYYMMDDHHMM = "yyyyMMddHHmm";

		public static final String CHINA_DEFAULT = "yyyy-MM-dd HH:mm:ss";

		public static final String YYYY_MM = "yyyy-MM";

		public static final String YYYY_MM_DD = "yyyy-MM-dd";

		public static final String YYYY_MM_DD_HH_MM = "yyyy-MM-dd HH:mm";

		public static final String YYYY_MM_DD_HH_MM_SS_SSS = "yyyy-MM-dd HH:mm:ss.SSS";
	}

	/**
	 * get now date.
	 * 
	 * @param pattern
	 * @return
	 */
	public static String now(String pattern) {
		return format(new Date(), pattern);
	}

	/**
	 * get now china date.
	 * 
	 * @return
	 */
	public static String chinaNow() {
		return format(new Date(), DatePatterns.CHINA_DEFAULT);
	}

	/**
	 * format date.
	 * 
	 * @param date
	 * @param pattern
	 * @return
	 */
	public static String format(Date date, String pattern) {
		try {
			SimpleDateFormat df = new SimpleDateFormat(pattern);
			return df.format(date);
		} catch (Exception e) {
			throw new ExamCloudRuntimeException(e);
		}
	}

	/**
	 * format now date.
	 *
	 * @author WANGWEI
	 * @param pattern
	 * @return
	 */
	public static String formatNow(String pattern) {
		try {
			SimpleDateFormat df = new SimpleDateFormat(pattern);
			return df.format(new Date());
		} catch (Exception e) {
			throw new ExamCloudRuntimeException(e);
		}
	}

	/**
	 * parse date.
	 * 
	 * @param source
	 * @param pattern
	 * @return
	 */
	public static Date parse(String source, String pattern) {
		SimpleDateFormat df = new SimpleDateFormat(pattern);
		try {
			return df.parse(source);
		} catch (ParseException e) {
			throw new ExamCloudRuntimeException(e);
		}
	}

	/**
	 * parse date randomly.
	 *
	 * @author WANGWEI
	 * @param s
	 * @return
	 */
	public static Date parseRandomly(String s) {
		if (s.matches("\\d{4}/\\d{1,2}/\\d{1,2}\\s+\\d{1,2}:\\d{1,2}:\\d{1,2}")) {
			return parse(s, "yyyy/MM/dd HH:mm:ss");
		} else if (s.matches("\\d{4}/\\d{1,2}/\\d{1,2}\\s+\\d{1,2}:\\d{1,2}")) {
			return parse(s, "yyyy/MM/dd HH:mm");
		} else if (s.matches("\\d{4}/\\d{1,2}/\\d{1,2}")) {
			return parse(s, "yyyy/MM/dd");
		} else if (s.matches("\\d{4}-\\d{1,2}-\\d{1,2}\\s+\\d{1,2}:\\d{1,2}:\\d{1,2}")) {
			return parse(s, "yyyy-MM-dd HH:mm:ss");
		} else if (s.matches("\\d{4}-\\d{1,2}-\\d{1,2}\\s+\\d{1,2}:\\d{1,2}")) {
			return parse(s, "yyyy-MM-dd HH:mm");
		} else if (s.matches("\\d{4}-\\d{1,2}-\\d{1,2}")) {
			return parse(s, "yyyy-MM-dd");
		} else {
			throw new ExamCloudRuntimeException("unsupported date string.");
		}
	}

	/**
	 * 解析excel日期
	 *
	 * @author WANGWEI
	 * @param number
	 * @return
	 */
	public static Date parseExcel(String number) {

		BigDecimal bd = new BigDecimal(number);
		int days = bd.intValue();
		int mills = (int) Math.round(bd.subtract(new BigDecimal(days)).doubleValue() * 24 * 3600);

		Calendar c = Calendar.getInstance();
		c.set(1900, 0, 1);
		c.add(Calendar.DATE, days - 2);
		int hour = mills / 3600;
		int minute = (mills - hour * 3600) / 60;
		int second = mills - hour * 3600 - minute * 60;
		c.set(Calendar.HOUR_OF_DAY, hour);
		c.set(Calendar.MINUTE, minute);
		c.set(Calendar.SECOND, second);

		Date date = c.getTime();

		return date;
	}

	/**
	 * 是否同一天
	 *
	 * @author WANGWEI
	 * @param date1
	 * @param date2
	 * @return
	 */
	public static boolean isSameDay(Date date1, Date date2) {
		if (null == date1) {
			throw new ExamCloudRuntimeException("first argument must not be null");
		}
		if (null == date2) {
			throw new ExamCloudRuntimeException("second argument must not be null");
		}

		Calendar cal1 = Calendar.getInstance();
		cal1.setTime(date1);
		Calendar cal2 = Calendar.getInstance();
		cal2.setTime(date2);
		return isSameDay(cal1, cal2);
	}

	/**
	 * 是否同一天
	 *
	 * @author WANGWEI
	 * @param calendar1
	 * @param calendar2
	 * @return
	 */
	public static boolean isSameDay(Calendar calendar1, Calendar calendar2) {
		if (null == calendar1) {
			throw new ExamCloudRuntimeException("first argument must not be null");
		}
		if (null == calendar2) {
			throw new ExamCloudRuntimeException("second argument must not be null");
		}
		return calendar1.get(0) == calendar2.get(0) && calendar1.get(1) == calendar2.get(1)
				&& calendar1.get(6) == calendar2.get(6);
	}

}