src/java/org/apache/cassandra/utils/obs/OpenBitSet.java
/**
   * clears a bit.
   * The index should be less than the OpenBitSet size.
   */
clears a bit.
The index should be less than the OpenBitSet size.
clears a bit . The index should be less than the OpenBitSet size .
public void clear(long index) {
    int wordNum = (int)(index >> 6); 
    int bit = (int)index & 0x3f;     
    long bitmask = 1L << bit;
    bits[wordNum / PAGE_SIZE][wordNum % PAGE_SIZE] &= ~bitmask;
  }
public void clear ( long index ) { int wordNum = ( int ) ( index >> 6 ) ; int bit = ( int ) index & 0x3f ; long bitmask = 1L << bit ; bits [ wordNum / PAGE_SIZE ] [ wordNum % PAGE_SIZE ] &= ~ bitmask ; }
clears a bit.
clears a bit .
// div 64 // mod 64