Use BitSet to mark holiday : BitSet « Collections « Java Tutorial

1. Java Tutorial
2. Collections
3. BitSet

import java.util.BitSet;

public class HolidaySked {
  BitSet sked;

  public HolidaySked() {
    sked = new BitSet(365);
    int[] holiday = { 1, 15, 50, 148, 185, 246, 281, 316, 326, 359 };
    for (int i = 0; i < holiday.length; i++) {
      addHoliday(holiday[i]);
    }
  }

  public void addHoliday(int dayToAdd) {
    sked.set(dayToAdd);
  }

  public boolean isHoliday(int dayToCheck) {
    boolean result = sked.get(dayToCheck);
    return result;
  }

  public static void main(String[] arguments) {
    HolidaySked cal = new HolidaySked();
    if (arguments.length > 0) {
      try {
        int whichDay = Integer.parseInt(arguments[0]);
        if (cal.isHoliday(whichDay)) {
          System.out.println("Day number " + whichDay + " is a holiday.");
        } else {
          System.out.println("Day number " + whichDay + " is not a holiday.");
        }
      } catch (NumberFormatException nfe) {
        System.out.println("Error: " + nfe.getMessage());
      }
    }
  }
}