code: public synchronized boolean remove(Object key)
                      throws IOException,
                      EOFException,
                      FileManagerException,
                      ClassNotFoundException,
                      HashtableOnDiskException {
          if (filemgr == null) {
              throw new HashtableOnDiskException("No Filemanager");
          }
  
          if (key == null)
              return false; // no null keys allowed
  
          HashtableEntry e = findEntry(key, RETRIEVE_KEY, !CHECK_EXPIRED);
          if (e == null)
              return false; // not found
  
          boolean answer = remove(e);
          htoddc.returnToHashtableEntryPool(e);
          return answer;
      }
docs: Removes the mapping for this key and deletes the object from disk.
  
  @param key The key of the object being removed.
  
  @return true if successful, false otherwise
  
  @exception FileManagerException The underlying file manager has a problem.
  @exception ClassNotFoundException Some key in the hash bucket cannot be
  deserialized while searching to see if the object already exists. The
  underlying file is likely corrupted.
  @exception IOException The underlying file has a problem and is likely
  corrupt.
  @exception EOFxception We were asked to seek beyond the end of the file.
  The file is likely corrupt.
  @exception HashtableOnDiskException The hashtable header is readable but invalid.
  One or more of the following is true: the magic string is invalid, the header
  pointers are null, the header pointers do not point to a recognizable hashtable.