mysqlio.java

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     * method uses the specified character encoding to get the bytes from the
     * query string.
     *
     * @param query DOCUMENT ME!
     * @param maxRows DOCUMENT ME!
     * @param characterEncoding DOCUMENT ME!
     * @param conn DOCUMENT ME!
     * @param resultSetType DOCUMENT ME!
     * @param streamResults DOCUMENT ME!
     * @param catalog DOCUMENT ME!
     *
     * @return DOCUMENT ME!
     *
     * @throws Exception DOCUMENT ME!
     */
    final ResultSet sqlQuery(String query, int maxRows,
        String characterEncoding, Connection conn, int resultSetType,
        boolean streamResults, String catalog) throws Exception {
        // We don't know exactly how many bytes we're going to get
        // from the query. Since we're dealing with Unicode, the
        // max is 2, so pad it (2 * query) + space for headers
        int packLength = HEADER_LENGTH + 1 + (query.length() * 2) + 2;

        if (this.sendPacket == null) {
            this.sendPacket = new Buffer(packLength);
        } else {
            this.sendPacket.clear();
        }

        this.sendPacket.writeByte((byte) MysqlDefs.QUERY);

        if (characterEncoding != null) {
            SingleByteCharsetConverter converter = this.connection
                .getCharsetConverter(characterEncoding);

            if (this.platformDbCharsetMatches) {
                this.sendPacket.writeStringNoNull(query, characterEncoding,
                    converter);
            } else {
                if (StringUtils.startsWithIgnoreCaseAndWs(query, "LOAD DATA")) {
                    this.sendPacket.writeBytesNoNull(query.getBytes());
                } else {
                    this.sendPacket.writeStringNoNull(query, characterEncoding,
                        converter);
                }
            }
        } else {
            this.sendPacket.writeStringNoNull(query);
        }

        return sqlQueryDirect(this.sendPacket, maxRows, conn, resultSetType,
            streamResults, catalog);
    }

    /**
     * Send a query stored in a packet directly to the server.
     *
     * @param queryPacket DOCUMENT ME!
     * @param maxRows DOCUMENT ME!
     * @param conn DOCUMENT ME!
     * @param resultSetType DOCUMENT ME!
     * @param streamResults DOCUMENT ME!
     * @param catalog DOCUMENT ME!
     *
     * @return DOCUMENT ME!
     *
     * @throws Exception DOCUMENT ME!
     */
    final ResultSet sqlQueryDirect(Buffer queryPacket, int maxRows,
        Connection conn, int resultSetType, boolean streamResults,
        String catalog) throws Exception {
        StringBuffer profileMsgBuf = null; // used if profiling
        long queryStartTime = 0;

        if (this.profileSql) {
            profileMsgBuf = new StringBuffer();
            queryStartTime = System.currentTimeMillis();

            byte[] queryBuf = queryPacket.getByteBuffer();

            // Extract the actual query from the network packet
            String query = new String(queryBuf, 5,
                    (queryPacket.getPosition() - 5));
            profileMsgBuf.append("Query\t\"");
            profileMsgBuf.append(query);
            profileMsgBuf.append("\"\texecution time:\t");
        }

        // Send query command and sql query string
        Buffer resultPacket = sendCommand(MysqlDefs.QUERY, null, queryPacket);

        if (this.profileSql) {
            long executionTime = System.currentTimeMillis() - queryStartTime;
            profileMsgBuf.append(executionTime);
            profileMsgBuf.append("\t");
        }

        resultPacket.setPosition(resultPacket.getPosition() - 1);

        long columnCount = resultPacket.readFieldLength();

        if (Driver.TRACE) {
            Debug.msg(this, "Column count: " + columnCount);
        }

        if (columnCount == 0) {
            if (this.profileSql) {
                System.err.println(profileMsgBuf.toString());
            }

            return buildResultSetWithUpdates(resultPacket);
        } else if (columnCount == Buffer.NULL_LENGTH) {
            String charEncoding = null;

            if (this.connection.useUnicode()) {
                charEncoding = this.connection.getEncoding();
            }

            String fileName = null;

            if (this.platformDbCharsetMatches) {
                fileName = ((charEncoding != null)
                    ? resultPacket.readString(charEncoding)
                    : resultPacket.readString());
            } else {
                fileName = resultPacket.readString();
            }

            return sendFileToServer(fileName);
        } else {
            long fetchStartTime = 0;

            if (this.profileSql) {
                fetchStartTime = System.currentTimeMillis();
            }

            com.mysql.jdbc.ResultSet results = getResultSet(columnCount,
                    maxRows, resultSetType, streamResults, catalog);

            if (this.profileSql) {
                long fetchElapsedTime = System.currentTimeMillis()
                    - fetchStartTime;
                profileMsgBuf.append("result set fetch time:\t");
                profileMsgBuf.append(fetchElapsedTime);
                System.err.println(profileMsgBuf.toString());
            }

            return results;
        }
    }

    /**
     * Returns the host this IO is connected to
     *
     * @return DOCUMENT ME!
     */
    String getHost() {
        return this.host;
    }

    /**
     * Does the version of the MySQL server we are connected to meet the given
     * minimums?
     *
     * @param major DOCUMENT ME!
     * @param minor DOCUMENT ME!
     * @param subminor DOCUMENT ME!
     *
     * @return DOCUMENT ME!
     */
    boolean versionMeetsMinimum(int major, int minor, int subminor) {
        if (getServerMajorVersion() >= major) {
            if (getServerMajorVersion() == major) {
                if (getServerMinorVersion() >= minor) {
                    if (getServerMinorVersion() == minor) {
                        return (getServerSubMinorVersion() >= subminor);
                    } else {
                        // newer than major.minor
                        return true;
                    }
                } else {
                    // older than major.minor
                    return false;
                }
            } else {
                // newer than major
                return true;
            }
        } else {
            return false;
        }
    }

    private final int readFully(InputStream in, byte[] b, int off, int len)
        throws IOException {
        if (len < 0) {
            throw new IndexOutOfBoundsException();
        }

        int n = 0;

        while (n < len) {
            int count = in.read(b, off + n, len - n);

            if (count < 0) {
                throw new EOFException();
            }

            n += count;
        }

        return n;
    }

    /**
     * Read one packet from the MySQL server
     *
     * @return DOCUMENT ME!
     *
     * @throws SQLException DOCUMENT ME!
     * @throws java.sql.SQLException DOCUMENT ME!
     */
    private final Buffer readPacket() throws SQLException {
        try {
            int lengthRead = readFully(mysqlInput, this.packetHeaderBuf, 0, 4);

            if (lengthRead < 4) {
                forceClose();
                throw new IOException("Unexpected end of input stream");
            }

            int packetLength = ((int) (this.packetHeaderBuf[0] & 0xff))
                + (((int) (this.packetHeaderBuf[1] & 0xff)) << 8)
                + (((int) (this.packetHeaderBuf[2] & 0xff)) << 16);

            byte multiPacketSeq = this.packetHeaderBuf[3];

            // Read data
            byte[] buffer = new byte[packetLength + 1];
            readFully(this.mysqlInput, buffer, 0, packetLength);
            buffer[packetLength] = 0;

            Buffer packet = new Buffer(buffer);

            return packet;
        } catch (IOException ioEx) {
            StringBuffer message = new StringBuffer(SQLError.get(
                        SQLError.SQL_STATE_COMMUNICATION_LINK_FAILURE));
            message.append(": ");
            message.append(ioEx.getClass().getName());
            message.append(", underlying cause: ");
            message.append(ioEx.getMessage());

            if (!this.connection.useParanoidErrorMessages()) {
                message.append(Util.stackTraceToString(ioEx));
            }

            throw new java.sql.SQLException(message.toString(),
                SQLError.SQL_STATE_COMMUNICATION_LINK_FAILURE, 0);
        }
    }

    private com.mysql.jdbc.ResultSet buildResultSetWithRows(String catalog,
        com.mysql.jdbc.Field[] fields, RowData rows, int resultSetConcurrency)
        throws SQLException {
        switch (resultSetConcurrency) {
        case java.sql.ResultSet.CONCUR_READ_ONLY:
            return new com.mysql.jdbc.ResultSet(catalog, fields, rows,
                this.connection);

        case java.sql.ResultSet.CONCUR_UPDATABLE:
            return new com.mysql.jdbc.UpdatableResultSet(catalog, fields, rows,
                this.connection);

        default:
            return new com.mysql.jdbc.ResultSet(catalog, fields, rows,
                this.connection);
        }
    }

    private com.mysql.jdbc.ResultSet buildResultSetWithUpdates(
        Buffer resultPacket) throws SQLException {
        long updateCount = -1;
        long updateID = -1;
        String info = null;

        try {
            if (this.useNewUpdateCounts) {
                updateCount = resultPacket.newReadLength();
                updateID = resultPacket.newReadLength();
            } else {
                updateCount = (long) resultPacket.readLength();
                updateID = (long) resultPacket.readLength();
            }

            if (this.connection.isReadInfoMsgEnabled()) {
                if (this.use41Extensions) {
                    int serverStatus = resultPacket.readInt();
                    int warningCount = resultPacket.readInt();

                    resultPacket.readByte(); // advance pointer
                }

                info = resultPacket.readString();
            }
        } catch (Exception ex) {
            throw new java.sql.SQLException(SQLError.get(
                    SQLError.SQL_STATE_GENERAL_ERROR) + ": "
                + ex.getClass().getName(), SQLError.SQL_STATE_GENERAL_ERROR, -1);
        }

        if (Driver.TRACE) {
            Debug.msg(this, "Update Count = " + updateCount);
        }

        ResultSet updateRs = new ResultSet(updateCount, updateID);

        if (info != null) {
            updateRs.setServerInfo(info);
        }

        return updateRs;
    }

    /**
     * Don't hold on to overly-large packets
     */
    private void reclaimLargeReusablePacket() {
        if ((this.reusablePacket != null)
                && (this.reusablePacket.getBufLength() > 1048576)) {
            this.reusablePacket = new Buffer(this.connection.getNetBufferLength());
        }
    }

    /**
     * Re-use a packet to read from the MySQL server
     *
     * @param reuse DOCUMENT ME!
     *
     * @return DOCUMENT ME!
     *
     * @throws SQLException DOCUMENT ME!
     * @throws SQLException DOCUMENT ME!
     */
    private final Buffer reuseAndReadPacket(Buffer reuse)
        throws SQLException {
        try {
            reuse.setWasMultiPacket(false);

            int lengthRead = readFully(mysqlInput, this.packetHeaderBuf, 0, 4);

            if (lengthRead < 4) {
                forceClose();
                throw new IOException("Unexpected end of input stream");
            }

            int packetLength = ((int) (this.packetHeaderBuf[0] & 0xff))
                + (((int) (this.packetHeaderBuf[1] & 0xff)) << 8)
                + (((int) (this.packetHeaderBuf[2] & 0xff)) << 16);

            byte multiPacketSeq = this.packetHeaderBuf[3];

            //byte multiPacketSeq = (byte) this.mysqlInput.read();
            // Set the Buffer to it's original state
            reuse.setPosition(0);
            reuse.setSendLength(0);

            // Do we need to re-alloc the byte buffer?
            //
            // Note: We actually check the length of the buffer,
            // rather than getBufLength(), because getBufLength() is not