public boolean contains(long prefix_hash){
  if (prefix_hash == 0) {
    return false;
  }
  int idx=-1 * Arrays.binarySearch(hashes_idx,prefix_hash) - 1;
  if (idx == cache_size) {
    return false;
  }
 else {
    return (hashes_idx[idx] & PREFIX_HASH_MASK) == prefix_hash;
  }
}

public boolean contains ( long prefix_hash ) { if ( prefix_hash == 0 ) { return false ; } int idx = - 1 * Arrays . binarySearch ( hashes_idx , prefix_hash ) - 1 ; if ( idx == cache_size ) { return false ; } else { return ( hashes_idx [ idx ] & PREFIX_HASH_MASK ) == prefix_hash ; } }
checks if there are any object in the cache generated on the base of encoding with prefix corresponding to the specified hash code .
