resultset.java

一个JDBC数据库连接的组件

     *
     * @param columnName is the SQL name of the column
     * @return the column value; if the value is SQL NULL, the result is 0
     * @exception SQLException if a database-access error occurs.
     */
    double getDouble(String columnName) throws SQLException;

    /**
     * Get the value of a column in the current row as a java.math.BigDecimal 
     * object.
     *
     * @param columnName is the SQL name of the column
     * @param scale the number of digits to the right of the decimal
     * @return the column value; if the value is SQL NULL, the result is null
     * @exception SQLException if a database-access error occurs.
     * @deprecated
     */
    BigDecimal getBigDecimal(String columnName, int scale) throws SQLException;

    /**
     * Get the value of a column in the current row as a Java byte array.
     * The bytes represent the raw values returned by the driver.
     *
     * @param columnName is the SQL name of the column
     * @return the column value; if the value is SQL NULL, the result is null
     * @exception SQLException if a database-access error occurs.
     */
    byte[] getBytes(String columnName) throws SQLException;

    /**
     * Get the value of a column in the current row as a java.sql.Date object.
     *
     * @param columnName is the SQL name of the column
     * @return the column value; if the value is SQL NULL, the result is null
     * @exception SQLException if a database-access error occurs.
     */
    java.sql.Date getDate(String columnName) throws SQLException;

    /**
     * Get the value of a column in the current row as a java.sql.Time object.
     *
     * @param columnName is the SQL name of the column
     * @return the column value; if the value is SQL NULL, the result is null
     * @exception SQLException if a database-access error occurs.
     */
    java.sql.Time getTime(String columnName) throws SQLException;

    /**
     * Get the value of a column in the current row as a java.sql.Timestamp object.
     *
     * @param columnName is the SQL name of the column
     * @return the column value; if the value is SQL NULL, the result is null
     * @exception SQLException if a database-access error occurs.
     */
    java.sql.Timestamp getTimestamp(String columnName) throws SQLException;

    /**
     * A column value can be retrieved as a stream of ASCII characters 
     * and then read in chunks from the stream.  This method is particularly
     * suitable for retrieving large LONGVARCHAR values.  The JDBC driver will
     * do any necessary conversion from the database format into ASCII.
     *
     * <P><B>Note:</B> All the data in the returned stream must
     * be read prior to getting the value of any other column. The
     * next call to a get method implicitly closes the stream.
     *
     * @param columnName is the SQL name of the column
     * @return a Java input stream that delivers the database column value
     * as a stream of one byte ASCII characters.  If the value is SQL NULL
     * then the result is null.
     * @exception SQLException if a database-access error occurs.
     */
    java.io.InputStream getAsciiStream(String columnName) throws SQLException;

    /**
     * A column value can be retrieved as a stream of Unicode characters 
     * and then read in chunks from the stream.  This method is particularly
     * suitable for retrieving large LONGVARCHAR values.  The JDBC driver will
     * do any necessary conversion from the database format into Unicode.
     *
     * <P><B>Note:</B> All the data in the returned stream must
     * be read prior to getting the value of any other column. The
     * next call to a get method implicitly closes the stream.
     *
     * @param columnName is the SQL name of the column
     * @return a Java input stream that delivers the database column value
     * as a stream of two byte Unicode characters.  If the value is SQL NULL
     * then the result is null.
     * @exception SQLException if a database-access error occurs.
     * @deprecated
     */
    java.io.InputStream getUnicodeStream(String columnName) throws SQLException;

    /**
     * A column value can be retrieved as a stream of uninterpreted bytes 
     * and then read in chunks from the stream.  This method is particularly
     * suitable for retrieving large LONGVARBINARY values.
     *
     * <P><B>Note:</B> All the data in the returned stream must
     * be read prior to getting the value of any other column. The
     * next call to a get method implicitly closes the stream.
     *
     * @param columnName is the SQL name of the column
     * @return a Java input stream that delivers the database column value
     * as a stream of uninterpreted bytes.  If the value is SQL NULL
     * then the result is null.
     * @exception SQLException if a database-access error occurs.
     */
    java.io.InputStream getBinaryStream(String columnName)
        throws SQLException;


    //=====================================================================
    // Advanced features:
    //=====================================================================

    /**
     * <p>The first warning reported by calls on this ResultSet is
     * returned. Subsequent ResultSet warnings will be chained to this
     * SQLWarning.
     *
     * <P>The warning chain is automatically cleared each time a new
     * row is read.
     *
     * <P><B>Note:</B> This warning chain only covers warnings caused
     * by ResultSet methods.  Any warning caused by statement methods
     * (such as reading OUT parameters) will be chained on the
     * Statement object. 
     *
     * @return the first SQLWarning or null 
     * @exception SQLException if a database-access error occurs.
     */
    SQLWarning getWarnings() throws SQLException;

    /**
     * After this call getWarnings returns null until a new warning is
     * reported for this ResultSet.  
     *
     * @exception SQLException if a database-access error occurs.
     */
    void clearWarnings() throws SQLException;

    /**
     * Get the name of the SQL cursor used by this ResultSet.
     *
     * <P>In SQL, a result table is retrieved through a cursor that is
     * named. The current row of a result can be updated or deleted
     * using a positioned update/delete statement that references the
     * cursor name. To insure that the cursor has the proper isolation
     * level to support update, the cursor's select statement should be 
     * of the form 'select for update'. If the 'for update' clause is 
     * omitted the positioned updates may fail.
     * 
     * <P>JDBC supports this SQL feature by providing the name of the
     * SQL cursor used by a ResultSet. The current row of a ResultSet
     * is also the current row of this SQL cursor.
     *
     * <P><B>Note:</B> If positioned update is not supported a
     * SQLException is thrown
     *
     * @return the ResultSet's SQL cursor name
     * @exception SQLException if a database-access error occurs.
     */
    String getCursorName() throws SQLException;

    /**
     * The number, types and properties of a ResultSet's columns
     * are provided by the getMetaData method.
     *
     * @return the description of a ResultSet's columns
     * @exception SQLException if a database-access error occurs.
     */
    ResultSetMetaData getMetaData() throws SQLException;

    /**
     * <p>Get the value of a column in the current row as a Java object.
     *
     * <p>This method will return the value of the given column as a
     * Java object.  The type of the Java object will be the default
     * Java object type corresponding to the column's SQL type,
     * following the mapping for built-in types specified in the JDBC 
     * spec.
     *
     * <p>This method may also be used to read datatabase specific
     * abstract data types.
     *
     * JDBC 2.0
     *
     * New behavior for getObject().
     * The behavior of method getObject() is extended to materialize  
     * data of SQL user-defined types.  When the column @i is a structured 
     * or distinct value, the behavior of this method is as if it were 
     * a call to: getObject(i, this.getStatement().getConnection().getTypeMap()).
     *
     * @param columnIndex the first column is 1, the second is 2, ...
     * @return a java.lang.Object holding the column value.  
     * @exception SQLException if a database-access error occurs.
     */
    Object getObject(int columnIndex) throws SQLException;

    /**
     * <p>Get the value of a column in the current row as a Java object.
     *
     * <p>This method will return the value of the given column as a
     * Java object.  The type of the Java object will be the default
     * Java object type corresponding to the column's SQL type,
     * following the mapping for built-in types specified in the JDBC 
     * spec.
     *
     * <p>This method may also be used to read datatabase specific
     * abstract data types.
     *
     * JDBC 2.0
     *
     * New behavior for getObject().
     * The behavior of method getObject() is extended to materialize  
     * data of SQL user-defined types.  When the column @i is a structured 
     * or distinct value, the behavior of this method is as if it were 
     * a call to: getObject(i, this.getStatement().getConnection().getTypeMap()).
     *
     * @param columnName is the SQL name of the column
     * @return a java.lang.Object holding the column value.  
     * @exception SQLException if a database-access error occurs.
     */
    Object getObject(String columnName) throws SQLException;

    //----------------------------------------------------------------

    /**
     * Map a Resultset column name to a ResultSet column index.
     *
     * @param columnName the name of the column
     * @return the column index
     * @exception SQLException if a database-access error occurs.
     */
    int findColumn(String columnName) throws SQLException;


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

    //---------------------------------------------------------------------
    // Getter's and Setter's
    //---------------------------------------------------------------------

    /**
     * JDBC 2.0
     *
     * <p>Get the value of a column in the current row as a java.io.Reader.
     */
    java.io.Reader getCharacterStream(int columnIndex) throws SQLException;

    /**
     * JDBC 2.0
     *
     * <p>Get the value of a column in the current row as a java.io.Reader.
     */
    java.io.Reader getCharacterStream(String columnName) throws SQLException;

    /**
     * JDBC 2.0
     *
     * Get the value of a column in the current row as a java.math.BigDecimal 
     * object.
     *
     * @param columnIndex the first column is 1, the second is 2, ...
     * @return the column value (full precision); if the value is SQL NULL, 
     * the result is null
     * @exception SQLException if a database-access error occurs.
     */
    BigDecimal getBigDecimal(int columnIndex) throws SQLException;

    /**
     * JDBC 2.0
     *
     * Get the value of a column in the current row as a java.math.BigDecimal 
     * object.
     *
     */
    BigDecimal getBigDecimal(String columnName) throws SQLException;

    //---------------------------------------------------------------------
    // Traversal/Positioning
    //---------------------------------------------------------------------

    /**
     * JDBC 2.0
     *
     * <p>Determine if the cursor is before the first row in the result 
     * set.   
     *
     * @return true if before the first row, false otherwise. Returns
     * false when the result set contains no rows.
     * @exception SQLException if a database-access error occurs.
     */
    boolean isBeforeFirst() throws SQLException;
      
    /**
     * JDBC 2.0
     *
     * <p>Determine if the cursor is after the last row in the result 
     * set.   
     *
     * @return true if after the last row, false otherwise.  Returns
     * false when the result set contains no rows.
     * @exception SQLException if a database-access error occurs.
     */
    boolean isAfterLast() throws SQLException;
 
    /**
     * JDBC 2.0
     *
     * <p>Determine if the cursor is on the first row of the result set.   
     *
     * @return true if on the first row, false otherwise.   
     * @exception SQLException if a database-access error occurs.
     */
    boolean isFirst() throws SQLException;
 
    /**
     * JDBC 2.0
     *
     * <p>Determine if the cursor is on the last row of the result set.   
     * Note: Calling isLast() may be expensive since the JDBC driver
     * might need to fetch ahead one row in order to determine 
     * whether the current row is the last row in the result set.
     *
     * @return true if on the last row, false otherwise. 
     * @exception SQLException if a database-access error occurs.
     */
    boolean isLast() throws SQLException;

    /**
     * JDBC 2.0
     *
     * <p>Moves to the front of the result set, just before the
     * first row. Has no effect if the result set contains no rows.
     *
     * @exception SQLException if a database-access error occurs, or
     * result set type is TYPE_FORWARD_ONLY
     */
    void beforeFirst() throws SQLException;

    /**
     * JDBC 2.0
     *
     * <p>Moves to the end of the result set, just after the last
     * row.  Has no effect if the result set contains no rows.
     *
     * @exception SQLException if a database-access error occurs, or
     * result set type is TYPE_FORWARD_ONLY.
     */
    void afterLast() throws SQLException;

    /**
     * JDBC 2.0
     *
     * <p>Moves to the first row in the result set.  
     *
     * @return true if on a valid row, false if no rows in the result set.
     * @exception SQLException if a database-access error occurs, or
     * result set type is TYPE_FORWARD_ONLY.
     */
    boolean first() throws SQLException;