Set Bit
by Isai Damier, Android Engineer @ Google

/***************************************************************************
 * Author: Isai Damier
 * Title: Set Bit
 * Project: geekviewpoint
 * Package: algorithms
 *
 * Statement:
 *   Given a bit sequence x, set the kth bit; where the zeroth (0th) bit is
 *   the least significant (rightmost) bit.
 *
 * Sample Input:  0010010010
 * Sample Output: 0010010011
 * 
 * Description: 
 *
 * Technical Details: Let x = 0010010010. Then only the 1st, 4th,
 *    and the 7th bits are set. The function setBit(x,0) would
 *    return 0010010011.
 *
 *    setBit is a two steps operation:
 *    step_1] Using the shift-left operator << create a bit
 *            sequence where only the kth bit is set.
 *    step_2] Take the bitwise OR of x and the sequence in step_1.
 *
 **************************************************************************/ 
 public int setBit(int x, int kth) {
  return x | (1 << kth);
}

import org.junit.Test;
import static org.junit.Assert.*;

public class BitwiseTest {

/**
   * Test of setBit method, of class Bitwise.
   */
  @Test
  public void testSetBit() {
    System.out.println(""setBit"");
    Bitwise bits = new Bitwise();
    int x = Integer.parseInt(""0010010010"",2);
    int a = Integer.parseInt(""0010010011"",2);
    int b = Integer.parseInt(""0010011010"",2);
    int c = Integer.parseInt(""0110010010"",2);

    assertEquals(a, bits.setBit(x, 0));
    assertEquals(b, bits.setBit(x, 3));
    assertEquals(c, bits.setBit(x, 8));
  }
}