本文為大家分享的都是常用的日期之間的比較方法,供以后參考。
熱身:獲取當前時間 
SimpleDateFormat df = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");//設置日期格式
String nowDate = df.format(new Date());// new Date()為獲取當前系統時間 
注:樓主一直以為date類型不如string類型隨心所欲,所以下面的比較都是string類型的date進行比較。如果你真的真的就是那么倔強,ok,下面是date轉string的方法: 
SimpleDateFormat df = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");//設置日期格式
String date = df.format(Date類型的時間); 
1.兩個string類型的日期比較大小
public static int compare_date(String DATE1, String DATE2) {     DateFormat df = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");     try {       Date dt1 = df.parse(DATE1);       Date dt2 = df.parse(DATE2);       if (dt1.getTime() > dt2.getTime()) {         System.out.println("dt1 在dt2前");         return 1;       } else if (dt1.getTime() < dt2.getTime()) {         System.out.println("dt1在dt2后");         return -1;       } else {         return 0;       }     } catch (Exception exception) {       exception.printStackTrace();     }     return 0;   }2.返回兩個string類型日期之間相差的天數 
public static int daysBetween(String smdate,String bdate){      SimpleDateFormat sdf=new SimpleDateFormat("yyyy-MM-dd");      Calendar cal = Calendar.getInstance();       long time1 = 0;     long time2 = 0;          try{       cal.setTime(sdf.parse(smdate));         time1 = cal.getTimeInMillis();         cal.setTime(sdf.parse(bdate));        time2 = cal.getTimeInMillis();      }catch(Exception e){       e.printStackTrace();     }     long between_days=(time2-time1)/(1000*3600*24);            return Integer.parseInt(String.valueOf(between_days));      }3.返回兩個string類型日期相差的小時數
public static int daysBetween2(String startTime, String endTime) {     SimpleDateFormat sdf=new SimpleDateFormat("yyyy-MM-dd HH");      Calendar cal = Calendar.getInstance();       long time1 = 0;     long time2 = 0;          try{        cal.setTime(sdf.parse(startTime));          time1 = cal.getTimeInMillis();          cal.setTime(sdf.parse(endTime));         time2 = cal.getTimeInMillis();      }catch(Exception e){       e.printStackTrace();     }     long between_days=(time2-time1)/(1000*3600);             return Integer.parseInt(String.valueOf(between_days));      }4.計算兩段日期的重合日期
/**   * 計算兩段日期的重合日期   * @param str1 開始日期1   * @param str2 結束日期1   * @param str3 開始日期2   * @param str4 結束日期2   * @return   * @throws Exception   */  public static Map<String,Object> comparisonRQ(String str1, String str2, String str3,      String str4) throws Exception {    String mesg = "";    DateFormat df = new SimpleDateFormat("yyyy-MM-dd");    String startdate = "";    String enddate = "";    try {      Date dt1 = df.parse(str1);      Date dt2 = df.parse(str2);      Date dt3 = df.parse(str3);      Date dt4 = df.parse(str4);      if (dt1.getTime()<=dt3.getTime()&&dt3.getTime()<=dt2.getTime()&&dt2.getTime()<=dt4.getTime()) {        mesg = "f";//重合        startdate = str3;        enddate = str2;      }      if (dt1.getTime()>=dt3.getTime()&&dt3.getTime()<=dt2.getTime()&&dt2.getTime()<=dt4.getTime()) {        mesg = "f";//重合        startdate = str1;        enddate = str2;      }            if (dt3.getTime()<=dt1.getTime()&&dt1.getTime()<=dt4.getTime()&&dt4.getTime()<=dt2.getTime()) {        mesg = "f";//重合        startdate = str1;        enddate = str4;      }      if (dt3.getTime()>=dt1.getTime()&&dt1.getTime()<=dt4.getTime()&&dt4.getTime()<=dt2.getTime()) {        mesg = "f";//重合        startdate = str3;        enddate = str4;      }            System.out.println(startdate+"----"+enddate);                }catch (ParseException e) {      e.printStackTrace();      throw new ParseException(e.getMessage(), 0);    }catch(Exception e){      e.printStackTrace();      throw new Exception(e);    }    Map<String,Object> map = new HashMap<String,Object>();    map.put("startdate", startdate);    map.put("enddate", enddate);    return map;  }以上就是本文的全部內容,希望對大家的學習有所幫助,也希望大家多多支持武林網。
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