updatableresultset.java

开发MySql数据库的最新JDBC驱动。

			return;
		}

		this.isUpdatable = true;
		this.notUpdatableReason = null;

		return;
	}

	/**
	 * JDBC 2.0 Delete the current row from the result set and the underlying
	 * database. Cannot be called when on the insert row.
	 * 
	 * @exception SQLException
	 *                if a database-access error occurs, or if called when on
	 *                the insert row.
	 * @throws SQLException
	 *             if the ResultSet is not updatable or some other error occurs
	 */
	public synchronized void deleteRow() throws SQLException {
		checkClosed();

		if (!this.isUpdatable) {
			throw new NotUpdatable(this.notUpdatableReason);
		}

		if (this.onInsertRow) {
			throw SQLError.createSQLException(Messages.getString("UpdatableResultSet.1")); //$NON-NLS-1$
		} else if (this.rowData.size() == 0) {
			throw SQLError.createSQLException(Messages.getString("UpdatableResultSet.2")); //$NON-NLS-1$
		} else if (isBeforeFirst()) {
			throw SQLError.createSQLException(Messages.getString("UpdatableResultSet.3")); //$NON-NLS-1$
		} else if (isAfterLast()) {
			throw SQLError.createSQLException(Messages.getString("UpdatableResultSet.4")); //$NON-NLS-1$
		}

		if (this.deleter == null) {
			if (this.deleteSQL == null) {
				generateStatements();
			}

			this.deleter = this.connection
					.clientPrepareStatement(this.deleteSQL);
		}

		this.deleter.clearParameters();

		String characterEncoding = null;

		if (this.connection.getUseUnicode()) {
			characterEncoding = this.connection.getEncoding();
		}

		//
		// FIXME: Use internal routines where possible for character
		// conversion!
		try {
			int numKeys = this.primaryKeyIndicies.size();

			if (numKeys == 1) {
				int index = ((Integer) this.primaryKeyIndicies.get(0))
						.intValue();
				String currentVal = ((characterEncoding == null) ? new String(
						(byte[]) this.thisRow[index]) : new String(
						(byte[]) this.thisRow[index], characterEncoding));
				this.deleter.setString(1, currentVal);
			} else {
				for (int i = 0; i < numKeys; i++) {
					int index = ((Integer) this.primaryKeyIndicies.get(i))
							.intValue();
					String currentVal = ((characterEncoding == null) ? new String(
							(byte[]) this.thisRow[index])
							: new String((byte[]) this.thisRow[index],
									characterEncoding));
					this.deleter.setString(i + 1, currentVal);
				}
			}

			this.deleter.executeUpdate();
			this.rowData.removeRow(this.rowData.getCurrentRowNumber());
		} catch (java.io.UnsupportedEncodingException encodingEx) {
			throw SQLError.createSQLException(Messages.getString("UpdatableResultSet.39", //$NON-NLS-1$
					new Object[] { this.charEncoding }) //$NON-NLS-1$
					, SQLError.SQL_STATE_ILLEGAL_ARGUMENT); //$NON-NLS-1$ //$NON-NLS-2$
		}
	}

	private synchronized void extractDefaultValues() throws SQLException {
		java.sql.DatabaseMetaData dbmd = this.connection.getMetaData();

		java.sql.ResultSet columnsResultSet = null;

		try {
			columnsResultSet = dbmd.getColumns(this.catalog, null,
					this.tableOnlyName, "%"); //$NON-NLS-1$

			HashMap columnNameToDefaultValueMap = new HashMap(
					this.fields.length /* at least this big... */);

			while (columnsResultSet.next()) {
				String columnName = columnsResultSet.getString("COLUMN_NAME"); //$NON-NLS-1$
				byte[] defaultValue = columnsResultSet.getBytes("COLUMN_DEF"); //$NON-NLS-1$

				columnNameToDefaultValueMap.put(columnName, defaultValue);
			}

			int numFields = this.fields.length;

			this.defaultColumnValue = new byte[numFields][];

			for (int i = 0; i < numFields; i++) {
				String defValTableName = this.fields[i].getOriginalName();

				if ((defValTableName == null)
						|| (defValTableName.length() == 0)) {
					defValTableName = this.fields[i].getName();
				}

				if (defValTableName != null) {
					byte[] defaultVal = (byte[]) columnNameToDefaultValueMap
							.get(defValTableName);

					this.defaultColumnValue[i] = defaultVal;
				}
			}
		} finally {
			if (columnsResultSet != null) {
				columnsResultSet.close();

				columnsResultSet = null;
			}
		}
	}

	/**
	 * JDBC 2.0
	 * 
	 * <p>
	 * Moves to the first row in the result set.
	 * </p>
	 * 
	 * @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.
	 */
	public synchronized boolean first() throws SQLException {
		return super.first();
	}

	/**
	 * Figure out whether or not this ResultSet is updateable, and if so,
	 * generate the PreparedStatements to support updates.
	 * 
	 * @throws SQLException
	 *             DOCUMENT ME!
	 * @throws NotUpdatable
	 *             DOCUMENT ME!
	 */
	protected synchronized void generateStatements() throws SQLException {
		if (!this.isUpdatable) {
			this.doingUpdates = false;
			this.onInsertRow = false;

			throw new NotUpdatable(this.notUpdatableReason);
		}

		String quotedId = getQuotedIdChar();

		if (this.fields[0].getOriginalTableName() != null) {
			StringBuffer tableNameBuffer = new StringBuffer();

			String databaseName = this.fields[0].getDatabaseName();

			if ((databaseName != null) && (databaseName.length() > 0)) {
				tableNameBuffer.append(quotedId);
				tableNameBuffer.append(databaseName);
				tableNameBuffer.append(quotedId);
				tableNameBuffer.append('.');
			}

			this.tableOnlyName = this.fields[0].getOriginalTableName();

			tableNameBuffer.append(quotedId);
			tableNameBuffer.append(this.tableOnlyName);
			tableNameBuffer.append(quotedId);

			this.qualifiedAndQuotedTableName = tableNameBuffer.toString();
		} else {
			StringBuffer tableNameBuffer = new StringBuffer();

			this.tableOnlyName = this.fields[0].getTableName();

			tableNameBuffer.append(quotedId);
			tableNameBuffer.append(this.tableOnlyName);
			tableNameBuffer.append(quotedId);

			this.qualifiedAndQuotedTableName = tableNameBuffer.toString();
		}

		this.primaryKeyIndicies = new ArrayList();

		StringBuffer fieldValues = new StringBuffer();
		StringBuffer keyValues = new StringBuffer();
		StringBuffer columnNames = new StringBuffer();
		StringBuffer insertPlaceHolders = new StringBuffer();
		boolean firstTime = true;
		boolean keysFirstTime = true;

		String equalsStr = this.connection.versionMeetsMinimum(3, 23, 0) ? "<=>"
				: "=";

		for (int i = 0; i < this.fields.length; i++) {
			String originalColumnName = this.fields[i].getOriginalName();
			String columnName = null;

			if (this.connection.getIO().hasLongColumnInfo()
					&& (originalColumnName != null)
					&& (originalColumnName.length() > 0)) {
				columnName = originalColumnName;
			} else {
				columnName = this.fields[i].getName();
			}

			if (this.fields[i].isPrimaryKey()) {
				this.primaryKeyIndicies.add(new Integer(i));

				if (!keysFirstTime) {
					keyValues.append(" AND "); //$NON-NLS-1$
				} else {
					keysFirstTime = false;
				}

				keyValues.append(quotedId);
				keyValues.append(columnName);
				keyValues.append(quotedId);
				keyValues.append(equalsStr);
				keyValues.append("?"); //$NON-NLS-1$
			}

			if (firstTime) {
				firstTime = false;
				fieldValues.append("SET "); //$NON-NLS-1$
			} else {
				fieldValues.append(","); //$NON-NLS-1$
				columnNames.append(","); //$NON-NLS-1$
				insertPlaceHolders.append(","); //$NON-NLS-1$
			}

			insertPlaceHolders.append("?"); //$NON-NLS-1$

			columnNames.append(quotedId);
			columnNames.append(columnName);
			columnNames.append(quotedId);

			fieldValues.append(quotedId);
			fieldValues.append(columnName);
			fieldValues.append(quotedId);
			fieldValues.append("=?"); //$NON-NLS-1$
		}

		this.updateSQL = "UPDATE " + this.qualifiedAndQuotedTableName + " " //$NON-NLS-1$ //$NON-NLS-2$
				+ fieldValues.toString() //$NON-NLS-1$ //$NON-NLS-2$
				+ " WHERE " + keyValues.toString(); //$NON-NLS-1$
		this.insertSQL = "INSERT INTO " + this.qualifiedAndQuotedTableName //$NON-NLS-1$
				+ " (" + columnNames.toString() //$NON-NLS-1$ //$NON-NLS-2$
				+ ") VALUES (" + insertPlaceHolders.toString() + ")"; //$NON-NLS-1$ //$NON-NLS-2$
		this.refreshSQL = "SELECT " + columnNames.toString() + " FROM " //$NON-NLS-1$ //$NON-NLS-2$
				+ this.qualifiedAndQuotedTableName //$NON-NLS-1$ //$NON-NLS-2$
				+ " WHERE " + keyValues.toString(); //$NON-NLS-1$
		this.deleteSQL = "DELETE FROM " + this.qualifiedAndQuotedTableName //$NON-NLS-1$
				+ " WHERE " //$NON-NLS-1$ //$NON-NLS-2$
				+ keyValues.toString();
	}

	private synchronized SingleByteCharsetConverter getCharConverter()
			throws SQLException {
		if (!this.initializedCharConverter) {
			this.initializedCharConverter = true;

			if (this.connection.getUseUnicode()) {
				this.charEncoding = connection.getEncoding();
				this.charConverter = this.connection
						.getCharsetConverter(this.charEncoding);
			}
		}

		return this.charConverter;
	}

	/**
	 * JDBC 2.0 Return the concurrency of this result set. The concurrency used
	 * is determined by the statement that created the result set.
	 * 
	 * @return the concurrency type, CONCUR_READ_ONLY, etc.
	 * 
	 * @exception SQLException
	 *                if a database-access error occurs
	 */
	public int getConcurrency() throws SQLException {
		return (this.isUpdatable ? CONCUR_UPDATABLE : CONCUR_READ_ONLY);
	}

	private synchronized String getQuotedIdChar() throws SQLException {
		if (this.quotedIdChar == null) {
			boolean useQuotedIdentifiers = this.connection
					.supportsQuotedIdentifiers();

			if (useQuotedIdentifiers) {
				java.sql.DatabaseMetaData dbmd = this.connection.getMetaData();
				this.quotedIdChar = dbmd.getIdentifierQuoteString();
			} else {
				this.quotedIdChar = ""; //$NON-NLS-1$
			}
		}

		return this.quotedIdChar;
	}

	/**
	 * JDBC 2.0 Insert the contents of the insert row into the result set and
	 * the database. Must be on the insert row when this method is called.
	 * 
	 * @exception SQLException
	 *                if a database-access error occurs, if called when not on
	 *                the insert row, or if all non-nullable columns in the
	 *                insert row have not been given a value
	 */
	public synchronized void insertRow() throws SQLException {
		checkClosed();

		if (!this.onInsertRow) {
			throw SQLError.createSQLException(Messages.getString("UpdatableResultSet.7")); //$NON-NLS-1$
		}

		this.inserter.executeUpdate();

		long autoIncrementId = this.inserter.getLastInsertID();
		int numFields = this.fields.length;
		byte[][] newRow = new byte[numFields][];

		for (int i = 0; i < numFields; i++) {
			if (this.inserter.isNull(i)) {
				newRow[i] = null;
			} else {
				newRow[i] = this.inserter.getBytesRepresentation(i);
			}

			//
			// WARN: This non-variant only holds if MySQL never allows more
			// than one auto-increment key (which is the way it is _today_)
			//
			if (this.fields[i].isAutoIncrement() && autoIncrementId > 0) {
				newRow[i] = String.valueOf(autoIncrementId).getBytes();
				this.inserter.setBytesNoEscapeNoQuotes(i + 1, newRow[i]);
			}
		}
		
		refreshRow(this.inserter, newRow);
		
		this.rowData.addRow(newRow);
		resetInserter();
	}


	/**
	 * JDBC 2.0
	 * 
	 * <p>
	 * Determine if the cursor is after the last row in the result set.
	 * </p>
	 * 
	 * @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.
	 */
	public synchronized boolean isAfterLast() throws SQLException {
		return super.isAfterLast();
	}

	/**
	 * JDBC 2.0
	 * 
	 * <p>
	 * Determine if the cursor is before the first row in the result set.
	 * </p>
	 * 
	 * @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.
	 */
	public synchronized boolean isBeforeFirst() throws SQLException {
		return super.isBeforeFirst();
	}

	/**
	 * JDBC 2.0
	 * 
	 * <p>
	 * Determine if the cursor is on the first row of the result set.
	 * </p>
	 * 
	 * @return true if on the first row, false otherwise.
	 * 
	 * @exception SQLException
	 *                if a database-access error occurs.
	 */
	public synchronized boolean isFirst() throws SQLException {
		return super.isFirst();
	}

	/**
	 * 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.
	 * </p>
	 * 
	 * @return true if on the last row, false otherwise.
	 * 
	 * @exception SQLException
	 *                if a database-access error occurs.
	 */
	public synchronized boolean isLast() throws SQLException {
		return super.isLast();
	}

	boolean isUpdatable() {
		return this.isUpdatable;
	}

	/**
	 * JDBC 2.0
	 *