/**
     * Initialize the revision manager.
     */
    public void initialize(Properties properties);

    /**
     * Opens the revision manager.
     *
     * @throws IOException
     */
    public void open() throws IOException;

    /**
     * Closes the revision manager.
     *
     * @throws IOException
     */
    public void close() throws IOException;

    /**
     * Start the write transaction.
     *
     * @param table The name of table involved in the transaction.
     * @param families The column families of table in which data will be written by the transaction.
     * @return An instance of Transaction
     * @throws IOException
     */
    public Transaction beginWriteTransaction(String table, List<String> families)
            throws IOException;

    /**
     * Start the write transaction.
     *
     * @param table The name of table involved in the transaction.
     * @param families The column families of table in which data will be written by the transaction.
     * @param keepAlive The duration ( in milliseconds) after which the transaction will expire. 
     * @return An instance of Transaction
     * @throws IOException
     */
    public Transaction beginWriteTransaction(String table,
            List<String> families, long keepAlive) throws IOException;

    /**
     * Commit the write transaction.
     *
     * @param transaction An instance of Transaction to be committed.
     * @throws IOException
     */
    public void commitWriteTransaction(Transaction transaction)
            throws IOException;

    /**
     * Abort the write transaction.
     *
     * @param transaction An instance of Transaction to be aborted.
     * @throws IOException
     */
    public void abortWriteTransaction(Transaction transaction)
            throws IOException;

    /**
     * Create the latest snapshot of the table.
     *
     * @param tableName The name of the table to create a snapshot.
     * @return An instance of TableSnapshot.
     * @throws IOException
     */
    public TableSnapshot createSnapshot(String tableName) throws IOException;

    /**
     * Create the snapshot of the table using the revision number.
     *
     * @param tableName The name of the table to create a snapshot.
     * @param revision The revision number to be used. 
     * @return An instance of TableSnapshot.
     * @throws IOException
     */
    public TableSnapshot createSnapshot(String tableName, long revision)
            throws IOException;

    /**
     * Extends the expiration of a transaction by the time indicated by keep alive.
     *
     * @param transaction An instance of Transaction.
     * @throws IOException
     */
    public void keepAlive(Transaction transaction) throws IOException;