monetresultset.java

这个是内存数据库的客户端

		throw new SQLException("No such columnname: " + columnName);
	}

	/**
	 * Moves the cursor to the first row in this ResultSet object.
	 *
	 * @return true if the cursor is on a valid row; false if there are no rows
	 *         in the result set
	 * @throws SQLException - if a database access error occurs or the result
	 *         set type is TYPE_FORWARD_ONLY
	 */
	public boolean first() throws SQLException {
		return(absolute(1));
	}

	public Array getArray(int i) throws SQLException { throw new SQLException("Method not implemented yet, sorry!"); }
	public Array getArray(String colName) throws SQLException { throw new SQLException("Method not implemented yet, sorry!"); }

	/* Mapi doesn't allow something for streams at the moment, thus all
	   not implemented for now */
	public InputStream getAsciiStream(int columnIndex) throws SQLException { throw new SQLException("Method not implemented yet, sorry!"); }
	public InputStream getAsciiStream(String columnName) throws SQLException { throw new SQLException("Method not implemented yet, sorry!"); }
	public InputStream getBinaryStream(int columnIndex) throws SQLException { throw new SQLException("Method not implemented yet, sorry!"); }
	public InputStream getBinaryStream(String columnName) throws SQLException { throw new SQLException("Method not implemented yet, sorry!"); }
	public InputStream getUnicodeStream(int columnIndex) throws SQLException { throw new SQLException("Method not implemented yet, sorry!"); }
	public InputStream getUnicodeStream(String columnName) throws SQLException { throw new SQLException("Method not implemented yet, sorry!"); }
	public Blob getBlob(int i) throws SQLException { throw new SQLException("Method not implemented yet, sorry!"); }
	public Blob getBlob(String colName) throws SQLException { throw new SQLException("Method not implemented yet, sorry!"); }
	public Reader getCharacterStream(int columnIndex) throws SQLException { throw new SQLException("Method not implemented yet, sorry!"); }
	public Reader getCharacterStream(String columnName) throws SQLException { throw new SQLException("Method not implemented yet, sorry!"); }

	/**
	 * Retrieves the value of the designated column in the current row
	 * of this ResultSet object as a Clob object in the
	 * Java programming language.
	 *
	 * @param i the first column is 1, the second is 2, ...
	 * @return a Clob object representing the SQL CLOB value in the
	 *         specified column
	 * @throws SQLException if a database access error occurs
	 */
	public Clob getClob(int i) throws SQLException {
		String tmp = getString(i);
		if (tmp == null) {
			return(null);
		} else {
			return(new MonetClob(tmp));
		}
	}

	/**
	 * Retrieves the value of the designated column in the current row
	 * of this ResultSet object as a Clob object in the
	 * Java programming language.
	 *
	 * @param colName the name of the column from which to retrieve
	 *        the value
	 * @return a Clob object representing the SQL CLOB value in the
	 *         specified column
	 * @throws SQLException if a database access error occurs
	 */
	public Clob getClob(String colName) throws SQLException {
		return(getClob(findColumn(colName)));
	}

	/**
	 * Retrieves the value of the designated column in the current row of this
	 * ResultSet object as a java.math.BigDecimal with full precision.
	 *
	 * @param columnIndex the first column is 1, the second is 2, ...
	 * @return the column value (full precision); if the value is SQL NULL,
	 *         the value returned is null in the Java programming language.
	 * @throws SQLException if a database access error occurs
	 */
	public BigDecimal getBigDecimal(int columnIndex) throws SQLException {
		String decimal = getString(columnIndex);
		if (decimal == null) {
			return(null);
		} else {
			try {
				return(new BigDecimal(decimal));
			} catch (NumberFormatException e) {
				return(new BigDecimal("0"));
			}
		}
	}

	/**
	 * Retrieves the value of the designated column in the current row of this
	 * ResultSet object as a java.math.BigDecimal with full precision.
	 *
	 * @param columnIndex the first column is 1, the second is 2, ...
	 * @param scale the number of digits to the right of the decimal point
	 * @return the column value (full precision); if the value is SQL NULL,
	 *         the value returned is null in the Java programming language.
	 * @throws SQLException if a database access error occurs
	 */
	public BigDecimal getBigDecimal(int columnIndex, int scale)
		throws SQLException
	{
		String decimal = getString(columnIndex);
		if (decimal == null) {
			return(null);
		} else {
			BigDecimal bd;
			try {
				bd = new BigDecimal(decimal);
			} catch (NumberFormatException e) {
				bd = new BigDecimal("0");
			}
			bd.setScale(scale);
			return(bd);
		}
	}

	/**
	 * Retrieves the value of the designated column in the current row of this
	 * ResultSet object as a java.math.BigDecimal with full precision.
	 *
	 * @param columnName the SQL name of the column
	 * @return the column value (full precision); if the value is SQL NULL,
	 *         the value returned is null in the Java programming language.
	 * @throws SQLException if a database access error occurs
	 */
	public BigDecimal getBigDecimal(String columnName) throws SQLException {
		return(getBigDecimal(findColumn(columnName)));
	}

	/**
	 * Retrieves the value of the designated column in the current row of this
	 * ResultSet object as a java.math.BigDecimal with full precision.
	 *
	 * @param columnName the SQL name of the column
	 * @param scale the number of digits to the right of the decimal point
	 * @return the column value (full precision); if the value is SQL NULL,
	 *         the value returned is null in the Java programming language.
	 * @throws SQLException if a database access error occurs
	 */
	public BigDecimal getBigDecimal(String columnName, int scale)
		throws SQLException
	{
		return(getBigDecimal(findColumn(columnName), scale));
	}

	// See Sun JDBC Specification 3.0 Table B-6
	/**
	 * Retrieves the value of the designated column in the current row of this
	 * ResultSet object as a boolean in the Java programming language.
	 *
	 * @param columnIndex the first column is 1, the second is 2, ...
	 * @return the column value; if the value is SQL NULL, the value returned
	 *         is false
	 * @throws SQLException if there is no such column
	 */
	public boolean getBoolean(int columnIndex) throws SQLException{
		int dataType = MonetDriver.getJavaType(types[columnIndex - 1]);
		if (dataType == Types.TINYINT ||
			dataType == Types.SMALLINT ||
			dataType == Types.INTEGER ||
			dataType == Types.BIGINT)
		{
			if (getLong(columnIndex) == 0L) {
				return(false);
			} else {
				return(true);
			}
		} else if (dataType == Types.REAL ||
			dataType == Types.FLOAT ||
			dataType == Types.DOUBLE)
		{
			if (getDouble(columnIndex) == 0.0) {
				return(false);
			} else {
				return(true);
			}
		} else if (dataType == Types.DECIMAL ||
			dataType == Types.NUMERIC)
		{
			if (getBigDecimal(columnIndex).compareTo(new BigDecimal(0.0)) == 0) {
				return(false);
			} else {
				return(true);
			}
		} else if (dataType == Types.BIT ||
			dataType == Types.BOOLEAN ||
			dataType == Types.CHAR ||
			dataType == Types.VARCHAR ||
			dataType == Types.LONGVARCHAR)
		{
			return((Boolean.valueOf(getString(columnIndex))).booleanValue());
		} else {
			throw new SQLException("Conversion from " + types[columnIndex - 1] + " to boolean type not supported");
		}
	}

	/**
	 * Retrieves the value of the designated column in the current row of this
	 * ResultSet object as a boolean in the Java programming language.
	 *
	 * @param columnName the SQL name of the column
	 * @return the column value; if the value is SQL NULL, the value returned
	 *         is false
	 * @throws SQLException if the ResultSet object does not contain columnName
	 */
	public boolean getBoolean(String columnName) throws SQLException {
		return(getBoolean(findColumn(columnName)));
	}

	/**
	 * Retrieves the value of the designated column in the current row of this
	 * ResultSet object as a byte in the Java programming language.
	 *
	 * @param columnIndex the first column is 1, the second is 2, ...
	 * @return the column value; if the value is SQL NULL, the value returned
	 *         is 0
	 * @throws SQLException if a database access error occurs
	 */
	public byte getByte(int columnIndex) throws SQLException {
		String bytes = getString(columnIndex);
		if (bytes == null || bytes.length() == 0) {
			return((byte)0);
		} else {
			return(bytes.getBytes()[0]);
		}
	}

	/**
	 * Retrieves the value of the designated column in the current row of this
	 * ResultSet object as a byte in the Java programming language.
	 *
	 * @param columnName the SQL name of the column
	 * @return the column value; if the value is SQL NULL, the value returned
	 *         is 0
	 * @throws SQLException if a database access error occurs
	 */
	public byte getByte(String columnName) throws SQLException {
		return(getByte(findColumn(columnName)));
	}

	/**
	 * Retrieves the value of the designated column in the current row of this
	 * ResultSet object as a byte array in the Java programming language. The
	 * bytes represent the raw values returned by the driver.
	 * <br /><br />
	 * NOTE: Since the mapi protocol is ASCII-based, this method only returns
	 *       Java byte representations of Strings, which is nothing more than
	 *       an encoding into a sequence of bytes using the platform's default
	 *       charset.
	 *
	 * @param columnIndex the first column is 1, the second is 2, ...
	 * @return the column value; if the value is SQL NULL, the value returned
	 *         is null
	 * @throws SQLException if a database access error occurs
	 */
	public byte[] getBytes(int columnIndex) throws SQLException {
		String bytes = getString(columnIndex);
		if (bytes == null) {
			return(null);
		} else {
			return(bytes.getBytes());
		}
	}

	/**
	 * Retrieves the value of the designated column in the current row of this
	 * ResultSet object as a byte array in the Java programming language. The
	 * bytes represent the raw values returned by the driver.
	 * <br /><br />
	 * NOTE: Since the mapi protocol is ASCII-based, this method only returns
	 *       Java byte representations of Strings, which is nothing more than
	 *       an encoding into a sequence of bytes using the platform's default
	 *       charset.
	 *
	 * @param columnName the SQL name of the column
	 * @return the column value; if the value is SQL NULL, the value returned
	 *         is null
	 * @throws SQLException if a database access error occurs
	 */
	public byte[] getBytes(String columnName) throws SQLException {
		return(getBytes(findColumn(columnName)));
	}

	/**
	 * Retrieves the concurrency mode of this ResultSet object. The concurrency
	 * used is determined by the Statement object that created the result set.
	 * <br /><br />
	 * NOTE: MonetDB only supports read-only result sets, and will always return
	 *       ResultSet.CONCUR_READ_ONLY
	 *
	 * @return the concurrency type, either ResultSet.CONCUR_READ_ONLY or
	 *         ResultSet.CONCUR_UPDATABLE
	 */
	public int getConcurrency() {
		return(concurrency);
	}

	/**
	 * Retrieves the name of the SQL cursor used by this ResultSet object.
	 * In SQL, a result table is retrieved through a cursor that is named.
	 * For MonetDB this is the tableID returned in a resultset header. The
	 * current row of a result set 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
	 * FOR UPDATE is omitted, the positioned updates may fail.
	 * <br /><br />
	 * The JDBC API supports this SQL feature by providing the name of the SQL
	 * cursor used by a ResultSet object. The current row of a ResultSet object
	 * is also the current row of this SQL cursor.
	 * <br /><br />
	 * Note: If positioned update is not supported, a SQLException is thrown.
	 *       MonetDB currently doesn't support updates, so the SQLException is
	 *       thrown for now.
	 *
	 * @return the SQL name for this ResultSet object's cursor
	 * @throws SQLException if a database access error occurs
	 */
	public String getCursorName() throws SQLException {
		throw new SQLException("Positioned updates not supported for this " +
							   "cursor (" + tableID + ")");
		//return("" + tableID);
	}

	/**
	 * Retrieves the value of the designated column in the current row of this
	 * ResultSet object as a double in the Java programming language.
	 *
	 * @param columnIndex the first column is 1, the second is 2, ...
	 * @return the column value; if the value is SQL NULL, the value returned
	 *         is 0
	 * @throws SQLException if there is no such column
	 */
	public double getDouble(int columnIndex) throws SQLException {
		double ret = 0;	// note: relaxing by compiler here
		String dbl = getString(columnIndex);
		if (dbl != null) {
			try {
				ret = Double.parseDouble(dbl);
			} catch (NumberFormatException e) {
				// ignore, return the default: 0
			}
			// do not catch SQLException for it is declared to be thrown
		}

		return(ret);
	}

	/**
	 * Retrieves the value of the designated column in the current row of this
	 * ResultSet object as a double in the Java programming language.
	 *
	 * @param columnName the SQL name of the column
	 * @return the column value; if the value is SQL NULL, the value returned
	 *         is 0
	 * @throws SQLException if the ResultSet object does not contain columnName
	 */
	public double getDouble(String columnName) throws SQLException {
		return(getDouble(findColumn(columnName)));
	}

	/**
	 * Retrieves the fetch direction for this ResultSet object.
	 * <b>currently not implemented</b>
	 *
	 * @return the current fetch direction for this ResultSet object
	 */
	public int getFetchDirection() {
		return(FETCH_FORWARD);
	}

	/**
	 * Retrieves the fetch size for this ResultSet object.
	 *
	 * @return the current fetch size for this ResultSet object