안드로이드 날짜관련 펑션모음

//날짜에 점을 넣어줌
public static String setDotDate(String day) {
   int size = day.length();
   StringBuffer sb = new StringBuffer(day);

   String dot = ".";

   if (size == 4) {
      sb.insert(2, dot);
   } else if (size == 6) {
      sb.insert(4, dot);
   } else if (size == 8) {
      sb.insert(4, dot);
      sb.insert(7, dot);
   }
   return sb.toString();
}
//시간에 ":"을 넣어줌

public static String setDotTime(String time) {
   int size = time.length();
   StringBuffer sb = new StringBuffer(time);

   String dot = ":";

   if (size == 4) {
      sb.insert(2, dot);
   } else if (size == 8) {
      sb.insert(4, dot);
      sb.insert(7, dot);
   } else if (size == 6) {
      sb.insert(2, dot);
      sb.insert(5, dot);
   }
   return sb.toString();
}
//현재 날짜가저오기

public static String getCurrentDay() {
   String day = "";
   Calendar calendar = Calendar.getInstance();
   int today = calendar.get(Calendar.DATE);

   calendar.set(Calendar.DAY_OF_MONTH, 1);

   int year = calendar.get(Calendar.YEAR);
   int month = calendar.get(Calendar.MONTH) + 1;

   day = addZero(year) + addZero(month) + addZero(today);

   return day;
}
//년월

public static String getCurrentMonth() {
   String day = "";
   Calendar calendar = Calendar.getInstance();
   int today = calendar.get(Calendar.DATE);

   calendar.set(Calendar.DAY_OF_MONTH, 1);

   int year = calendar.get(Calendar.YEAR);
   int month = calendar.get(Calendar.MONTH) + 1;

   day = addZero(year) + addZero(month);

   return day;
}
//내일

public static String getTomorrow() {
   String day = "";
   Calendar cal = new GregorianCalendar();
   cal.add(Calendar.DATE, 1);

   int year = cal.get(Calendar.YEAR);
   int month = cal.get(Calendar.MONTH) + 1;
   int today = cal.get(Calendar.DAY_OF_MONTH);

   day = addZero(year) + addZero(month) + addZero(today);

   return day;
}
//"0"이 없을때 붙여줌.

public static String addZero(int arg) {
   String val = String.valueOf(arg);

   if (arg < 10)
      val = "0" + val;

   return val;
}
//현재시간

public static String getCurrentTime() {
   String strNow = "";
   // 현재 시간을 msec으로 구한다.
   long now = System.currentTimeMillis();
   // 현재 시간을 저장 한다.
   Date date = new Date(now);
   // 시간 포맷으로 만든다.
   SimpleDateFormat sdfNow = new SimpleDateFormat("yyMMddHHmmss");
   strNow = sdfNow.format(date);

   return strNow;
}
//요일

public static String getDayOfWeek() {

   String dayOfWeek = "";

   Calendar cal = Calendar.getInstance();
   int day_of_week = cal.get(Calendar.DAY_OF_WEEK);

   switch (day_of_week) {
      case 1:
         dayOfWeek = "일";
         break;
      case 2:
         dayOfWeek = "월";
         break;
      case 3:
         dayOfWeek = "화";
         break;
      case 4:
         dayOfWeek = "수";
         break;
      case 5:
         dayOfWeek = "목";
         break;
      case 6:
         dayOfWeek = "금";
         break;
      case 7:
         dayOfWeek = "토";
         break;
   }

   return dayOfWeek;
}
//현재시간

public static String getCurrentTimeHHMM() {
   String strNow = "";
   // 현재 시간을 msec으로 구한다.
   long now = System.currentTimeMillis();
   // 현재 시간을 저장 한다.
   Date date = new Date(now);
   // 시간 포맷으로 만든다.
   SimpleDateFormat sdfNow = new SimpleDateFormat("HH:mm");
   strNow = sdfNow.format(date);

   return strNow;
}
//8자리 날짜를 넣으면 요일구함

public static String getDayOfWeek(String date) {

   int year = 0;
   int month = 0;
   int day = 0;

   if (date.length() > 7) {
      year = Integer.parseInt(date.substring(0, 4));
      month = Integer.parseInt(date.substring(4, 6));
      day = Integer.parseInt(date.substring(6, 8));
   }
   String dayOfWeek = "";

   Calendar cal = Calendar.getInstance();
   cal.set(Calendar.YEAR, year);
   cal.set(Calendar.MONTH, month - 1);
   cal.set(Calendar.DATE, day);

   int day_of_week = cal.get(Calendar.DAY_OF_WEEK);

   switch (day_of_week) {
      case 1:
         dayOfWeek = "일";
         break;
      case 2:
         dayOfWeek = "월";
         break;
      case 3:
         dayOfWeek = "화";
         break;
      case 4:
         dayOfWeek = "수";
         break;
      case 5:
         dayOfWeek = "목";
         break;
      case 6:
         dayOfWeek = "금";
         break;
      case 7:
         dayOfWeek = "토";
         break;
   }

   return dayOfWeek;
}
//"년,월,일"을 붙여줌

public static String addDate(String day) {
   int size = day.length();
   StringBuffer sb = new StringBuffer(day);

   if (size == 8) {
      sb.insert(4, "년 ");
      sb.insert(8, "월 ");
      sb.insert(12, "일 ");
   }
   return sb.toString();
}