基于springboot+mysql+jsp的学生宿舍管理系统

package com.util; import java.sql.Timestamp; import java.text.ParseException; import java.text.ParsePosition; import java.text.SimpleDateFormat; import java.util.Calendar; import java.util.Date; public final class DateUtil { /** 日期格式,指定到日期. */ public static final String DATE_FORMAT_DATE = "yyyy-MM-dd"; /** 日期格式,指定到时分秒. */ public static final String DATE_FORMAT_TIME = "yyyy-MM-dd HH:mm:ss"; /** 日期格式,指定到时分. */ public static final String DATE_FORMAT_MINUTE = "yyyy-MM-dd HH:mm"; /** 日期格式,指定到年. */ public static final String DATE_FORMAT_YEAR_NAME = "yyyy"; /** 日期格式,指定到月. */ public static final String DATE_FORMAT_MONTH_NAME = "yyyyMM"; /** 日期格式,指定到日. */ public static final String DATE_FORMAT_DATE_NAME = "yyyyMMdd"; /** 开始时间后缀 */ public static final String TIME_START_SUFFIX = " 00:00:00"; /** 结束时间后缀 */ public static final String TIME_END_SUFFIX = " 23:59:59"; /** 日期格式,指定到时分秒纯数字 */ public static final String DATE_FORMAT_TIME_MILL_NUMBER = "yyyyMMddHHmmss"; /** * Instantiates a new date util. */ private DateUtil() { // do not } public static String getDateStrByTimestamp(Object intt) { if (intt==null) return ""; String rtString = ""; String str = String.valueOf(intt); if (str.matches("^[0-9]*$")) { SimpleDateFormat format = new SimpleDateFormat(DATE_FORMAT_TIME); Timestamp tt = new Timestamp(Integer.valueOf(String.valueOf(intt))); rtString = format.format(tt); } else { rtString = str.substring(0,19); } return rtString; } /** * Timestamp格式的日期转换成String字符串. * * @param t * the t * @return the string */ public static String timestampToDateString(Timestamp t) { SimpleDateFormat format = new SimpleDateFormat(DATE_FORMAT_DATE); Timestamp tt = t; if (tt == null) { tt = new Timestamp(System.currentTimeMillis()); } return format.format(tt); } /** * Timestamp格式的日期转换成String字符串. * * @param t * the t * @return the string */ public static String timestampToDateString2(Timestamp t) { SimpleDateFormat format = new SimpleDateFormat(DATE_FORMAT_TIME); Timestamp tt = t; if (tt == null) { tt = new Timestamp(System.currentTimeMillis()); } return format.format(tt); } /** * 字符串格式的时间转换成Timestamp类型,将时间转换为Timestamp. * * @param dateStr * the date str * @return the timestamp */ public static Timestamp stringToTimestamp(String dateStr) { SimpleDateFormat sp = new SimpleDateFormat(DATE_FORMAT_TIME); return stringToTimestamp0(dateStr, sp); } /** * 字符串格式的时间转换成Timestamp类型.该方法作为一个底层方法. * * @param dateStr * the date str * @param sp * the sp * @return the timestamp */ private static Timestamp stringToTimestamp0(String dateStr, SimpleDateFormat sp) { String str = dateStr.trim(); if (str.length() < 8) { return new Timestamp(System.currentTimeMillis()); } else { return new Timestamp(sp.parse(dateStr, new ParsePosition(0)).getTime()); } } /** * 字符串格式的时间转换成Timestamp类型,将日期转换为Timestamp. * * @param dateStr * the date str * @return the timestamp */ public static Timestamp stringToTimestampWithDate(String dateStr) { SimpleDateFormat sp = new SimpleDateFormat(DATE_FORMAT_DATE); return stringToTimestamp0(dateStr, sp); } /** * 获取当前时间,格式为yyyy-MM-dd HH:mm:ss. * * @return the current date time */ public static String getCurrentDateTime() { return timestampToDatetimeString(new Timestamp(System.currentTimeMillis())); } public static String getCurrentDateNumber() { SimpleDateFormat format = new SimpleDateFormat(DATE_FORMAT_TIME_MILL_NUMBER); return format.format(new Timestamp(System.currentTimeMillis())); } /** * 获取当前日期,格式为yyyy-MM-dd. * * @return the current date */ public static String getCurrentDate() { return timestampToDateString(new Timestamp(System.currentTimeMillis())); } /** * 按照yyyy-MM-dd HH:mm:ss格式,格式化时间. * * @param t * the t * @return the string */ public static String timestampToDatetimeString(Timestamp t) { SimpleDateFormat format = new SimpleDateFormat(DATE_FORMAT_TIME); return format.format(t); } /** * 计算begin和end相差的天数. * * @param begin * the begin * @param end * the end * @return the long */ public static long dateInterval(String begin, String end) { SimpleDateFormat formatter = new SimpleDateFormat(DATE_FORMAT_DATE); try { Date beginDate = formatter.parse(begin); Date endDate = formatter.parse(end); if (endDate.getTime() - beginDate.getTime() > 0) { return (endDate.getTime() - beginDate.getTime()) / (24 * 60 * 60 * 1000l) + 1; } else { return 0; } } catch (ParseException e) { e.printStackTrace(); return 0; } } /** * 计算begin和end相差的秒数. * * @param begin * the begin * @param end * the end * @return the long */ public static long secondsDiff(String begin, String end) { SimpleDateFormat formatter = new SimpleDateFormat(DATE_FORMAT_TIME); try { Date beginDate = formatter.parse(begin); Date endDate = formatter.parse(end); if (endDate.getTime() - beginDate.getTime() > 0) { return (endDate.getTime() - beginDate.getTime()) / 1000l; } else { return 0; } } catch (ParseException e) { e.printStackTrace(); return 0; } } /** * 计算begin和end相差的秒数. * * @param begin * the begin * @param end * the end * @return the long */ public static long secondInterval(String begin, String end) { SimpleDateFormat formatter = new SimpleDateFormat(DATE_FORMAT_TIME); try { Date beginDate = formatter.parse(begin); Date endDate = formatter.parse(end); if (endDate.getTime() - beginDate.getTime() > 0) { return (endDate.getTime() - beginDate.getTime()); } else { return 0; } } catch (ParseException e) { e.printStackTrace(); return 0; } } /** * 计算begin和end相差的分钟数. * * @param begin * the begin * @param end * the end * @return the long */ public static long minuteInterval(String begin, String end) { SimpleDateFormat formatter = new SimpleDateFormat(DATE_FORMAT_MINUTE); try { Date beginDate = formatter.parse(begin); Date endDate = formatter.parse(end); if (endDate.getTime() - beginDate.getTime() > 0) { return (endDate.getTime() - beginDate.getTime()) / (60 * 1000l); } else { return 0; } } catch (ParseException e) { e.printStackTrace(); return 0; } } /** * 获取当前时间以前某天的日期,具体到时分秒. * * @param days * the days * @return the before current with days */ public static String getBeforeCurrentWithDays(int days) { return timestampToDatetimeString(new Timestamp(System.currentTimeMillis() - (days * 24 * 60 * 60 * 1000l))); } /** * 获取当前时间以后某天的日期,具体到时分秒. * * @param days * the days * @return the before current with days */ public static String getAfterCurrentWithDays(int days) { return timestampToDatetimeString(new Timestamp(System.currentTimeMillis() + (days * 24 * 60 * 60 * 1000l))); } /** * 获取当前时间几天以后的时间.格式为