statement.java

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     */
    boolean execute(String sql) throws SQLException;
	
    /**
     *  Retrieves the current result as a <code>ResultSet</code> object. 
     *  This method should be called only once per result.
     *
     * @return the current result as a <code>ResultSet</code> object or
     * <code>null</code> if the result is an update count or there are no more results
     * @exception SQLException if a database access error occurs
     * @see #execute 
     */
    ResultSet getResultSet() throws SQLException; 

    /**
     *  Retrieves the current result as an update count;
     *  if the result is a <code>ResultSet</code> object or there are no more results, -1
     *  is returned. This method should be called only once per result.
     * 
     * @return the current result as an update count; -1 if the current result is a
     * <code>ResultSet</code> object or there are no more results
     * @exception SQLException if a database access error occurs
     * @see #execute 
     */
    int getUpdateCount() throws SQLException; 

    /**
     * Moves to this <code>Statement</code> object's next result, returns
     * <code>true</code> if it is a <code>ResultSet</code> object, and
     * implicitly closes any current <code>ResultSet</code>
     * object(s) obtained with the method <code>getResultSet</code>.
     *
     * <P>There are no more results when the following is true:
     * <PRE>
     *     // stmt is a Statement object
     *     ((stmt.getMoreResults() == false) && (stmt.getUpdateCount() == -1))
     * </PRE>
     *
     * @return <code>true</code> if the next result is a <code>ResultSet</code>
     *         object; <code>false</code> if it is an update count or there are 
     *         no more results
     * @exception SQLException if a database access error occurs
     * @see #execute 
     */
    boolean getMoreResults() throws SQLException; 


    //--------------------------JDBC 2.0-----------------------------


    /**
     * Gives the driver a hint as to the direction in which
     * rows will be processed in <code>ResultSet</code>
     * objects created using this <code>Statement</code> object.  The 
     * default value is <code>ResultSet.FETCH_FORWARD</code>.
     * <P>
     * Note that this method sets the default fetch direction for 
     * result sets generated by this <code>Statement</code> object.
     * Each result set has its own methods for getting and setting
     * its own fetch direction.
     *
     * @param direction the initial direction for processing rows
     * @exception SQLException if a database access error occurs
     * or the given direction
     * is not one of <code>ResultSet.FETCH_FORWARD</code>,
     * <code>ResultSet.FETCH_REVERSE</code>, or <code>ResultSet.FETCH_UNKNOWN</code>
     * @since 1.2
     * @see #getFetchDirection
     */
    void setFetchDirection(int direction) throws SQLException;

    /**
     * Retrieves the direction for fetching rows from
     * database tables that is the default for result sets
     * generated from this <code>Statement</code> object.
     * If this <code>Statement</code> object has not set
     * a fetch direction by calling the method <code>setFetchDirection</code>,
     * the return value is implementation-specific.
     *
     * @return the default fetch direction for result sets generated
     *          from this <code>Statement</code> object
     * @exception SQLException if a database access error occurs
     * @since 1.2
     * @see #setFetchDirection
     */
    int getFetchDirection() throws SQLException;

    /**
     * Gives the JDBC driver a hint as to the number of rows that should 
     * be fetched from the database when more rows are needed.  The number 
     * of rows specified affects only result sets created using this 
     * statement. If the value specified is zero, then the hint is ignored.
     * The default value is zero.
     *
     * @param rows the number of rows to fetch
     * @exception SQLException if a database access error occurs, or the
     *        condition 0 <= <code>rows</code> <= <code>this.getMaxRows()</code> 
     *        is not satisfied.
     * @since 1.2
     * @see #getFetchSize
     */
    void setFetchSize(int rows) throws SQLException;
  
    /**
     * Retrieves the number of result set rows that is the default 
     * fetch size for <code>ResultSet</code> objects
     * generated from this <code>Statement</code> object.
     * If this <code>Statement</code> object has not set
     * a fetch size by calling the method <code>setFetchSize</code>,
     * the return value is implementation-specific.
     *
     * @return the default fetch size for result sets generated
     *          from this <code>Statement</code> object
     * @exception SQLException if a database access error occurs
     * @since 1.2
     * @see #setFetchSize
     */
    int getFetchSize() throws SQLException;

    /**
     * Retrieves the result set concurrency for <code>ResultSet</code> objects
     * generated by this <code>Statement</code> object.
     *
     * @return either <code>ResultSet.CONCUR_READ_ONLY</code> or
     * <code>ResultSet.CONCUR_UPDATABLE</code>
     * @exception SQLException if a database access error occurs
     * @since 1.2
     */
    int getResultSetConcurrency() throws SQLException;

    /**
     * Retrieves the result set type for <code>ResultSet</code> objects
     * generated by this <code>Statement</code> object.
     *
     * @return one of <code>ResultSet.TYPE_FORWARD_ONLY</code>,
     * <code>ResultSet.TYPE_SCROLL_INSENSITIVE</code>, or	
     * <code>ResultSet.TYPE_SCROLL_SENSITIVE</code>
     * @exception SQLException if a database access error occurs
     * @since 1.2
     */
    int getResultSetType()  throws SQLException;

    /**
     * Adds the given SQL command to the current list of commmands for this
     * <code>Statement</code> object. The commands in this list can be
     * executed as a batch by calling the method <code>executeBatch</code>.
     * <P>
     * <B>NOTE:</B>  This method is optional.
     *
     * @param sql typically this is a static SQL <code>INSERT</code> or 
     * <code>UPDATE</code> statement
     * @exception SQLException if a database access error occurs, or the
     * driver does not support batch updates
     * @see #executeBatch
     * @since 1.2
     */
    void addBatch( String sql ) throws SQLException;

    /**
     * Empties this <code>Statement</code> object's current list of 
     * SQL commands.
     * <P>
     * <B>NOTE:</B>  This method is optional.
     *
     * @exception SQLException if a database access error occurs or the
     * driver does not support batch updates
     * @see #addBatch
     * @since 1.2
     */
    void clearBatch() throws SQLException;

    /**
     * Submits a batch of commands to the database for execution and
     * if all commands execute successfully, returns an array of update counts.
     * The <code>int</code> elements of the array that is returned are ordered
     * to correspond to the commands in the batch, which are ordered 
     * according to the order in which they were added to the batch.
     * The elements in the array returned by the method <code>executeBatch</code>
     * may be one of the following:
     * <OL>
     * <LI>A number greater than or equal to zero -- indicates that the
     * command was processed successfully and is an update count giving the
     * number of rows in the database that were affected by the command's
     * execution
     * <LI>A value of <code>SUCCESS_NO_INFO</code> -- indicates that the command was
     * processed successfully but that the number of rows affected is
     * unknown
     * <P> 
     * If one of the commands in a batch update fails to execute properly,
     * this method throws a <code>BatchUpdateException</code>, and a JDBC
     * driver may or may not continue to process the remaining commands in
     * the batch.  However, the driver's behavior must be consistent with a
     * particular DBMS, either always continuing to process commands or never
     * continuing to process commands.  If the driver continues processing
     * after a failure, the array returned by the method
     * <code>BatchUpdateException.getUpdateCounts</code>
     * will contain as many elements as there are commands in the batch, and
     * at least one of the elements will be the following:
     * <P> 
     * <LI>A value of <code>EXECUTE_FAILED</code> -- indicates that the command failed
     * to execute successfully and occurs only if a driver continues to
     * process commands after a command fails
     * </OL>
     * <P>
     * A driver is not required to implement this method.
     * The possible implementations and return values have been modified in
     * the Java 2 SDK, Standard Edition, version 1.3 to
     * accommodate the option of continuing to proccess commands in a batch
     * update after a <code>BatchUpdateException</code> obejct has been thrown.
     *
     * @return an array of update counts containing one element for each
     * command in the batch.  The elements of the array are ordered according 
     * to the order in which commands were added to the batch.
     * @exception SQLException if a database access error occurs or the
     * driver does not support batch statements. Throws {@link BatchUpdateException}
     * (a subclass of <code>SQLException</code>) if one of the commands sent to the
     * database fails to execute properly or attempts to return a result set.
     * @since 1.3
     */
    int[] executeBatch() throws SQLException;

    /**
     * Retrieves the <code>Connection</code> object
     * that produced this <code>Statement</code> object.
     * @return the connection that produced this statement
     * @exception SQLException if a database access error occurs
     * @since 1.2
     */
    Connection getConnection()  throws SQLException;

  //--------------------------JDBC 3.0-----------------------------
    
    /** 
     * The constant indicating that the current <code>ResultSet</code> object 
     * should be closed when calling <code>getMoreResults</code>.
     *
     * @since 1.4
     */
    int CLOSE_CURRENT_RESULT = 1;

    /**
     * The constant indicating that the current <code>ResultSet</code> object
     * should not be closed when calling <code>getMoreResults</code>.
     *
     * @since 1.4
     */
    int KEEP_CURRENT_RESULT = 2;

    /**
     * The constant indicating that all <code>ResultSet</code> objects that
     * have previously been kept open should be closed when calling
     * <code>getMoreResults</code>.
     *
     * @since 1.4
     */
    int CLOSE_ALL_RESULTS = 3;

    /**
     * The constant indicating that a batch statement executed successfully
     * but that no count of the number of rows it affected is available.
     *
     * @since 1.4
     */
    int SUCCESS_NO_INFO = -2;

    /**
     * The constant indicating that an error occured while executing a
     * batch statement.