code: static public long createInstance(FileManager fm,
                                        int tablesize,
                                        int load)
                      throws IOException,
                      HashtableOnDiskException {
          HashHeader header = new HashHeader(fm, magic, load, tablesize);
          return header.disklocation;
      }
docs: ***********************************************************************
  createInstance Creates a new instance of a HTOD and stores a pointer
  to its header on disk so it can be retrived later, when
  reinitializing the HTOD.
  
  @param filemgr The FileManager instance over which the HTOD is
  implemented.
  @param instanceid The unique id for this new instance. If a persistent
  structure already exists with this instance the
  createInstance method will return false.
  @param tablesize The initial number of entries in the hashtable.
  @param load The hashtable load factor. This is what determines when
  the hashtable automatically increases its size. Let
  num_objects the number of objects in the hashtable, and
  ht_size be the number of buckets. When
  num_objects > (tablesize * load) the hashtable will automatically
  double the number of buckets and rehash each existing object.
  Note that is is used only if auto_rehash is "true" when
  instantiating the HTOD object via getInstance.
  @return true if the instance was created
  @return false if an instance with the specified id already exists.
  ***********************************************************************