Java: Checking if a bit is 0 or 1 in a long

Question

What method would you use to determine if the the bit that represents 2^x is a 1 or 0 ?

Answer 1

I coded a little static class which is doing some of the bit operation stuff.

public final class Bitfield {

  private Bitfield() {}

  // ********************************************************************
  // * TEST
  // ********************************************************************

  public static boolean testBit(final int pos, final int bitfield) {
      return (bitfield & (1 << pos)) == (1 << pos);
  }

  public static boolean testNum(final int num, final int bitfield) {
      return (bitfield & num) == num;
  }

  // ********************************************************************
  // * SET
  // ********************************************************************

  public static int setBit(final int pos, final int bitfield) {
     return bitfield | (1 << pos);
  }

  public static int addNum(final int number, final int bitfield) {
      return bitfield | number;
  }

  // ********************************************************************
  // * CLEAR
  // ********************************************************************

  public static int clearBit(final int pos, final int bitfield) {
      return bitfield ^ (1 << pos);
  }

  public static int clearNum(final int num, final int bitfield) {
      return bitfield ^ num;
  }

  }

If there are some questions flying around, just write me an email.

Good Programming!