Java工具类DateUtils实例详解

本文实例为大家分享了Java工具类DateUtils的具体代码，供大家参考，具体内容如下

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

public class DateUtils {

  public static String DATE_FORMAT = "yyyy-MM-dd";

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

  public static String DATE_FORMAT_CHINESE = "yyyy年M月d日";

  
  public static String getCurrentDate() {
    String datestr = null;
    SimpleDateFormat df = new SimpleDateFormat(DateUtils.DATE_FORMAT);
    datestr = df.format(new Date());
    return datestr;
  }

  
  public static String getCurrentDateTime() {
    String datestr = null;
    SimpleDateFormat df = new SimpleDateFormat(DateUtils.DATE_TIME_FORMAT);
    datestr = df.format(new Date());
    return datestr;
  }

  
  public static String getCurrentDateTime(String Dateformat) {
    String datestr = null;
    SimpleDateFormat df = new SimpleDateFormat(Dateformat);
    datestr = df.format(new Date());
    return datestr;
  }

  public static String dateToDateTime(Date date) {
    String datestr = null;
    SimpleDateFormat df = new SimpleDateFormat(DateUtils.DATE_TIME_FORMAT);
    datestr = df.format(date);
    return datestr;
  }
  
  public static Date stringToDate(String datestr) {

      if(datestr ==null ||datestr.equals("")){
 return null;
      }
    Date date = new Date();
    SimpleDateFormat df = new SimpleDateFormat(DateUtils.DATE_FORMAT);
    try {
      date = df.parse(datestr);
    } catch (ParseException e) {
      date=DateUtils.stringToDate(datestr,"yyyyMMdd");
    }
    return date;
  }

  
  public static Date stringToDate(String datestr, String dateformat) {
    Date date = new Date();
    SimpleDateFormat df = new SimpleDateFormat(dateformat);
    try {
      date = df.parse(datestr);
    } catch (ParseException e) {
      e.printStackTrace();
    }
    return date;
  }




  
  public static String dateToString(Date date) {
    String datestr = null;
    SimpleDateFormat df = new SimpleDateFormat(DateUtils.DATE_FORMAT);
    datestr = df.format(date);
    return datestr;
  }

  
  public static String dateToString(Date date, String dateformat) {
    String datestr = null;
    SimpleDateFormat df = new SimpleDateFormat(dateformat);
    datestr = df.format(date);
    return datestr;
  }

  
  public static int getDayOfDate(Date date) {
    int d = 0;
    Calendar cd = Calendar.getInstance();
    cd.setTime(date);
    d = cd.get(Calendar.DAY_OF_MONTH);
    return d;
  }

  
  public static int getMonthOfDate(Date date) {
    int m = 0;
    Calendar cd = Calendar.getInstance();
    cd.setTime(date);
    m = cd.get(Calendar.MONTH) + 1;
    return m;
  }

  
  public static int getYearOfDate(Date date) {
    int y = 0;
    Calendar cd = Calendar.getInstance();
    cd.setTime(date);
    y = cd.get(Calendar.YEAR);
    return y;
  }

  
  public static int getWeekOfDate(Date date) {
    int wd = 0;
    Calendar cd = Calendar.getInstance();
    cd.setTime(date);
    wd = cd.get(Calendar.DAY_OF_WEEK) - 1;
    return wd;
  }

  
  public static Date getFirstDayOfMonth(Date date) {
    Calendar cd = Calendar.getInstance();
    cd.setTime(date);
    cd.set(Calendar.DAY_OF_MONTH, 1);
    return cd.getTime();
  }

  
  public static Date getLastDayOfMonth(Date date) {
    return DateUtils.addDay(DateUtils.getFirstDayOfMonth(DateUtils.addMonth(date, 1)), -1);
  }

  
  public static boolean isLeapYEAR(Date date) {

    Calendar cd = Calendar.getInstance();
    cd.setTime(date);
    int year = cd.get(Calendar.YEAR);

    if (year % 4 == 0 && year % 100 != 0 | year % 400 == 0) {
      return true;
    } else {
      return false;
    }
  }

  
  public static Date getDateByYMD(int year, int month, int day) {
    Calendar cd = Calendar.getInstance();
    cd.set(year, month-1, day);
    return cd.getTime();
  }

  
  public static Date getYearCycleOfDate(Date date, int iyear) {
    Calendar cd = Calendar.getInstance();
    cd.setTime(date);

    cd.add(Calendar.YEAR, iyear);

    return cd.getTime();
  }

  
  public static Date getMonthCycleOfDate(Date date, int i) {
    Calendar cd = Calendar.getInstance();
    cd.setTime(date);

    cd.add(Calendar.MONTH, i);

    return cd.getTime();
  }

  
  public static int getYearByMinusDate(Date fromDate, Date toDate) {
    Calendar df=Calendar.getInstance();
    df.setTime(fromDate);

    Calendar dt=Calendar.getInstance();
    dt.setTime(toDate);

    return dt.get(Calendar.YEAR)-df.get(Calendar.YEAR);
  }

  
  public static int getMonthByMinusDate(Date fromDate, Date toDate) {
    Calendar df=Calendar.getInstance();
    df.setTime(fromDate);

    Calendar dt=Calendar.getInstance();
    dt.setTime(toDate);

    return dt.get(Calendar.YEAR)*12+dt.get(Calendar.MONTH)-
 (df.get(Calendar.YEAR)*12+df.get(Calendar.MONTH));
  }

  
  public static long getDayByMinusDate(Object fromDate, Object toDate) {

    Date f=DateUtils.chgObject(fromDate);

    Date t=DateUtils.chgObject(toDate);

    long fd=f.getTime();
    long td=t.getTime();

    return (td-fd)/(24L * 60L * 60L * 1000L);
  }

  
  public static int calcAge(Date birthday, Date calcDate) {

    int cYear=DateUtils.getYearOfDate(calcDate);
    int cMonth=DateUtils.getMonthOfDate(calcDate);
    int cDay=DateUtils.getDayOfDate(calcDate);   
    int bYear=DateUtils.getYearOfDate(birthday);
    int bMonth=DateUtils.getMonthOfDate(birthday);
    int bDay=DateUtils.getDayOfDate(birthday);

    if(cMonth>bMonth||(cMonth==bMonth&&cDay>bDay)){
      return cYear-bYear;
    }else{
      return cYear-1-bYear;
    }
  }

  
  public static String getBirthDayFromIDCard(String idno) {
    Calendar cd = Calendar.getInstance();
    if (idno.length() == 15) {
      cd.set(Calendar.YEAR, Integer.valueOf("19" + idno.substring(6, 8))
   .intValue());
      cd.set(Calendar.MONTH, Integer.valueOf(idno.substring(8, 10))
   .intValue() - 1);
      cd.set(Calendar.DAY_OF_MONTH,
   Integer.valueOf(idno.substring(10, 12)).intValue());
    } else if (idno.length() == 18) {
      cd.set(Calendar.YEAR, Integer.valueOf(idno.substring(6, 10))
   .intValue());
      cd.set(Calendar.MONTH, Integer.valueOf(idno.substring(10, 12))
   .intValue() - 1);
      cd.set(Calendar.DAY_OF_MONTH,
   Integer.valueOf(idno.substring(12, 14)).intValue());
    }
    return DateUtils.dateToString(cd.getTime());
  }

  
  public static Date addDay(Date date, int iday) {
    Calendar cd = Calendar.getInstance();

    cd.setTime(date);

    cd.add(Calendar.DAY_OF_MONTH, iday);

    return cd.getTime();
  }

  
  public static Date addMonth(Date date, int imonth) {
    Calendar cd = Calendar.getInstance();

    cd.setTime(date);

    cd.add(Calendar.MONTH, imonth);

    return cd.getTime();
  }

  
  public static Date addYear(Date date, int iyear) {
    Calendar cd = Calendar.getInstance();

    cd.setTime(date);

    cd.add(Calendar.YEAR, iyear);

    return cd.getTime();
  }

  
  public static Date chgObject(Object date){

    if(date!=null&&date instanceof Date){
      return (Date)date;
    }

    if(date!=null&&date instanceof String){
      return DateUtils.stringToDate((String)date);
    }

    return null;

  }

  public static long getAgeByBirthday(String date){

    Date birthday = stringToDate(date, "yyyy-MM-dd");
    long sec = new Date().getTime() - birthday.getTime();

    long age = sec/(1000*60*60*24)/365;

    return age;
  }


  
  public static void main(String[] args) {
    //String temp = DateUtil.dateToString(getLastDayOfMonth(new Date()),
    ///   DateUtil.DATE_FORMAT_CHINESE);
    //String s=DateUtil.dateToString(DateUtil.addDay(DateUtil.addYear(new Date(),1),-1));


    long s=DateUtils.getDayByMinusDate("2012-01-01", "2012-12-31");
    System.err.println(s);


  }

}

以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持考高分网。