public void free(){
  int useCount=_useCount.decrementAndGet();
  if (useCount == 0) {
    remove();
  }
 else   if (useCount < 0) {
    throw new IllegalStateException("illegal use count: " + useCount);
  }
}

public void free ( ) { int useCount = _useCount . decrementAndGet ( ) ; if ( useCount == 0 ) { remove ( ) ; } else if ( useCount < 0 ) { throw new IllegalStateException ( "illegal use count: " + useCount ) ; } }
allocates access to the inode .
