Java Code Examples for com.taobao.tddl.dbsync.binlog.LogBuffer#limit()

/**
 * Creates a new <code>Rotate_log_event</code> object read normally from
 * log.
 * 
 * @throws MySQLExtractException
 */
public RotateLogEvent(LogHeader header, LogBuffer buffer, FormatDescriptionLogEvent descriptionEvent){
    super(header);

    final int headerSize = descriptionEvent.commonHeaderLen;
    final int postHeaderLen = descriptionEvent.postHeaderLen[ROTATE_EVENT - 1];

    buffer.position(headerSize + R_POS_OFFSET);
    position = (postHeaderLen != 0) ? buffer.getLong64() : 4; // !uint8korr(buf
                                                              // +
                                                              // R_POS_OFFSET)

    final int filenameOffset = headerSize + postHeaderLen;
    int filenameLen = buffer.limit() - filenameOffset;
    if (filenameLen > FN_REFLEN - 1) filenameLen = FN_REFLEN - 1;
    buffer.position(filenameOffset);

    filename = buffer.getFixString(filenameLen);
}
 

/**
 * Creates a new <code>Rotate_log_event</code> object read normally from
 * log.
 * 
 * @throws MySQLExtractException
 */
public RotateLogEvent(LogHeader header, LogBuffer buffer, FormatDescriptionLogEvent descriptionEvent){
    super(header);

    final int headerSize = descriptionEvent.commonHeaderLen;
    final int postHeaderLen = descriptionEvent.postHeaderLen[ROTATE_EVENT - 1];

    buffer.position(headerSize + R_POS_OFFSET);
    position = (postHeaderLen != 0) ? buffer.getLong64() : 4; // !uint8korr(buf
                                                              // +
                                                              // R_POS_OFFSET)

    final int filenameOffset = headerSize + postHeaderLen;
    int filenameLen = buffer.limit() - filenameOffset;
    if (filenameLen > FN_REFLEN - 1) filenameLen = FN_REFLEN - 1;
    buffer.position(filenameOffset);

    filename = buffer.getFixString(filenameLen);
}
 

public CreateFileLogEvent(LogHeader header, LogBuffer buffer, FormatDescriptionLogEvent descriptionEvent){
    super(header, buffer, descriptionEvent);

    final int headerLen = descriptionEvent.commonHeaderLen;
    final int loadHeaderLen = descriptionEvent.postHeaderLen[LOAD_EVENT - 1];
    final int createFileHeaderLen = descriptionEvent.postHeaderLen[CREATE_FILE_EVENT - 1];

    copyLogEvent(buffer,
        ((header.type == LOAD_EVENT) ? (loadHeaderLen + headerLen) : (headerLen + loadHeaderLen + createFileHeaderLen)),
        descriptionEvent);

    if (descriptionEvent.binlogVersion != 1) {
        fileId = buffer.getUint32(headerLen + loadHeaderLen + CF_FILE_ID_OFFSET);
        /*
         * Note that it's ok to use get_data_size() below, because it is
         * computed with values we have already read from this event
         * (because we called copy_log_event()); we are not using slave's
         * format info to decode master's format, we are really using
         * master's format info. Anyway, both formats should be identical
         * (except the common_header_len) as these Load events are not
         * changed between 4.0 and 5.0 (as logging of LOAD DATA INFILE does
         * not use Load_log_event in 5.0).
         */
        blockLen = buffer.limit() - buffer.position();
        blockBuf = buffer.duplicate(blockLen);
    } else {
        initedFromOld = true;
    }
}
 

public AppendBlockLogEvent(LogHeader header, LogBuffer buffer, FormatDescriptionLogEvent descriptionEvent){
    super(header);

    final int commonHeaderLen = descriptionEvent.commonHeaderLen;
    final int postHeaderLen = descriptionEvent.postHeaderLen[header.type - 1];
    final int totalHeaderLen = commonHeaderLen + postHeaderLen;

    buffer.position(commonHeaderLen + AB_FILE_ID_OFFSET);
    fileId = buffer.getUint32();

    buffer.position(postHeaderLen);
    blockLen = buffer.limit() - totalHeaderLen;
    blockBuf = buffer.duplicate(blockLen);
}
 

public HeartbeatLogEvent(LogHeader header, LogBuffer buffer, FormatDescriptionLogEvent descriptionEvent){
    super(header);

    final int commonHeaderLen = descriptionEvent.commonHeaderLen;
    identLen = buffer.limit() - commonHeaderLen;
    if (identLen > FN_REFLEN - 1) {
        identLen = FN_REFLEN - 1;
    }

    logIdent = buffer.getFullString(commonHeaderLen, identLen, LogBuffer.ISO_8859_1);
}
 

public FormatDescriptionLogEvent(LogHeader header, LogBuffer buffer, FormatDescriptionLogEvent descriptionEvent)
                                                                                                                throws IOException{
    /* Start_log_event_v3 */
    super(header, buffer, descriptionEvent);

    buffer.position(LOG_EVENT_MINIMAL_HEADER_LEN + ST_COMMON_HEADER_LEN_OFFSET);
    commonHeaderLen = buffer.getUint8();
    if (commonHeaderLen < OLD_HEADER_LEN) /* sanity check */
    {
        throw new IOException("Format Description event header length is too short");
    }

    numberOfEventTypes = buffer.limit() - (LOG_EVENT_MINIMAL_HEADER_LEN + ST_COMMON_HEADER_LEN_OFFSET + 1);

    // buffer.position(LOG_EVENT_MINIMAL_HEADER_LEN
    // + ST_COMMON_HEADER_LEN_OFFSET + 1);
    postHeaderLen = new short[numberOfEventTypes];
    for (int i = 0; i < numberOfEventTypes; i++) {
        postHeaderLen[i] = (short) buffer.getUint8();
    }

    calcServerVersionSplit();
    long calc = getVersionProduct();
    if (calc >= checksumVersionProduct) {
        /*
         * the last bytes are the checksum alg desc and value (or value's
         * room)
         */
        numberOfEventTypes -= BINLOG_CHECKSUM_ALG_DESC_LEN;
    }

    if (logger.isInfoEnabled()) logger.info("common_header_len= " + commonHeaderLen + ", number_of_event_types= "
                                            + numberOfEventTypes);
}
 

public RowsQueryLogEvent(LogHeader header, LogBuffer buffer, FormatDescriptionLogEvent descriptionEvent){
    super(header, buffer, descriptionEvent);

    final int commonHeaderLen = descriptionEvent.commonHeaderLen;
    final int postHeaderLen = descriptionEvent.postHeaderLen[header.type - 1];

    /*
     * m_rows_query length is stored using only one byte, but that length is
     * ignored and the complete query is read.m_rows_query长度只使用一个字节存储，但是这个长度是
     *被忽略，然后读取完整的查询。
     */
    int offset = commonHeaderLen + postHeaderLen + 1;
    int len = buffer.limit() - offset;
    rowsQuery = buffer.getFullString(offset, len, LogBuffer.ISO_8859_1);
}
 

public AnnotateRowsEvent(LogHeader header, LogBuffer buffer, FormatDescriptionLogEvent descriptionEvent){
    super(header, buffer, descriptionEvent);

    final int commonHeaderLen = descriptionEvent.getCommonHeaderLen();
    final int postHeaderLen = descriptionEvent.getPostHeaderLen()[header.getType() - 1];

    int offset = commonHeaderLen + postHeaderLen;
    int len = buffer.limit() - offset;
    rowsQuery = buffer.getFullString(offset, len, LogBuffer.ISO_8859_1);
}
 

public FormatDescriptionLogEvent(LogHeader header, LogBuffer buffer, FormatDescriptionLogEvent descriptionEvent)
                                                                                                                throws IOException{
    /* Start_log_event_v3 */
    super(header, buffer, descriptionEvent);

    buffer.position(LOG_EVENT_MINIMAL_HEADER_LEN + ST_COMMON_HEADER_LEN_OFFSET);
    commonHeaderLen = buffer.getUint8();
    if (commonHeaderLen < OLD_HEADER_LEN) /* sanity check */
    {
        throw new IOException("Format Description event header length is too short");
    }

    numberOfEventTypes = buffer.limit() - (LOG_EVENT_MINIMAL_HEADER_LEN + ST_COMMON_HEADER_LEN_OFFSET + 1);

    // buffer.position(LOG_EVENT_MINIMAL_HEADER_LEN
    // + ST_COMMON_HEADER_LEN_OFFSET + 1);
    postHeaderLen = new short[numberOfEventTypes];
    for (int i = 0; i < numberOfEventTypes; i++) {
        postHeaderLen[i] = (short) buffer.getUint8();
    }

    calcServerVersionSplit();
    long calc = getVersionProduct();
    if (calc >= checksumVersionProduct) {
        /*
         * the last bytes are the checksum alg desc and value (or value's
         * room)
         */
        numberOfEventTypes -= BINLOG_CHECKSUM_ALG_DESC_LEN;
    }

    if (logger.isInfoEnabled()) logger.info("common_header_len= " + commonHeaderLen + ", number_of_event_types= "
                                            + numberOfEventTypes);
}
 

public AnnotateRowsEvent(LogHeader header, LogBuffer buffer, FormatDescriptionLogEvent descriptionEvent){
    super(header, buffer, descriptionEvent);

    final int commonHeaderLen = descriptionEvent.getCommonHeaderLen();
    final int postHeaderLen = descriptionEvent.getPostHeaderLen()[header.getType() - 1];

    int offset = commonHeaderLen + postHeaderLen;
    int len = buffer.limit() - offset;
    rowsQuery = buffer.getFullString(offset, len, LogBuffer.ISO_8859_1);
}
 

public CreateFileLogEvent(LogHeader header, LogBuffer buffer, FormatDescriptionLogEvent descriptionEvent){
    super(header, buffer, descriptionEvent);

    final int headerLen = descriptionEvent.commonHeaderLen;
    final int loadHeaderLen = descriptionEvent.postHeaderLen[LOAD_EVENT - 1];
    final int createFileHeaderLen = descriptionEvent.postHeaderLen[CREATE_FILE_EVENT - 1];

    copyLogEvent(buffer,
        ((header.type == LOAD_EVENT) ? (loadHeaderLen + headerLen) : (headerLen + loadHeaderLen + createFileHeaderLen)),
        descriptionEvent);

    if (descriptionEvent.binlogVersion != 1) {
        fileId = buffer.getUint32(headerLen + loadHeaderLen + CF_FILE_ID_OFFSET);
        /*
         * Note that it's ok to use get_data_size() below, because it is
         * computed with values we have already read from this event
         * (because we called copy_log_event()); we are not using slave's
         * format info to decode master's format, we are really using
         * master's format info. Anyway, both formats should be identical
         * (except the common_header_len) as these Load events are not
         * changed between 4.0 and 5.0 (as logging of LOAD DATA INFILE does
         * not use Load_log_event in 5.0).
         */
        blockLen = buffer.limit() - buffer.position();
        blockBuf = buffer.duplicate(blockLen);
    } else {
        initedFromOld = true;
    }
}
 

public RowsQueryLogEvent(LogHeader header, LogBuffer buffer, FormatDescriptionLogEvent descriptionEvent){
    super(header, buffer, descriptionEvent);

    final int commonHeaderLen = descriptionEvent.commonHeaderLen;
    final int postHeaderLen = descriptionEvent.postHeaderLen[header.type - 1];

    /*
     * m_rows_query length is stored using only one byte, but that length is
     * ignored and the complete query is read.
     */
    int offset = commonHeaderLen + postHeaderLen + 1;
    int len = buffer.limit() - offset;
    rowsQuery = buffer.getFullString(offset, len, LogBuffer.ISO_8859_1);
}
 

public AppendBlockLogEvent(LogHeader header, LogBuffer buffer, FormatDescriptionLogEvent descriptionEvent){
    super(header);

    final int commonHeaderLen = descriptionEvent.commonHeaderLen;
    final int postHeaderLen = descriptionEvent.postHeaderLen[header.type - 1];
    final int totalHeaderLen = commonHeaderLen + postHeaderLen;

    buffer.position(commonHeaderLen + AB_FILE_ID_OFFSET);
    fileId = buffer.getUint32();

    buffer.position(postHeaderLen);
    blockLen = buffer.limit() - totalHeaderLen;
    blockBuf = buffer.duplicate(blockLen);
}
 

public HeartbeatLogEvent(LogHeader header, LogBuffer buffer, FormatDescriptionLogEvent descriptionEvent){
    super(header);

    final int commonHeaderLen = descriptionEvent.commonHeaderLen;
    identLen = buffer.limit() - commonHeaderLen;
    if (identLen > FN_REFLEN - 1) {
        identLen = FN_REFLEN - 1;
    }

    logIdent = buffer.getFullString(commonHeaderLen, identLen, LogBuffer.ISO_8859_1);
}
 

public RowsLogEvent(LogHeader header, LogBuffer buffer, FormatDescriptionLogEvent descriptionEvent, boolean partial){
    super(header);

    final int commonHeaderLen = descriptionEvent.commonHeaderLen;
    final int postHeaderLen = descriptionEvent.postHeaderLen[header.type - 1];
    int headerLen = 0;
    buffer.position(commonHeaderLen + RW_MAPID_OFFSET);
    if (postHeaderLen == 6) {
        /*
         * Master is of an intermediate source tree before 5.1.4. Id is 4
         * bytes
         */
        tableId = buffer.getUint32();
    } else {
        tableId = buffer.getUlong48(); // RW_FLAGS_OFFSET
    }
    flags = buffer.getUint16();

    if (postHeaderLen == FormatDescriptionLogEvent.ROWS_HEADER_LEN_V2) {
        headerLen = buffer.getUint16();
        headerLen -= 2;
        int start = buffer.position();
        int end = start + headerLen;
        for (int i = start; i < end;) {
            switch (buffer.getUint8(i++)) {
                case RW_V_EXTRAINFO_TAG:
                    // int infoLen = buffer.getUint8();
                    buffer.position(i + EXTRA_ROW_INFO_LEN_OFFSET);
                    int checkLen = buffer.getUint8(); // EXTRA_ROW_INFO_LEN_OFFSET
                    int val = checkLen - EXTRA_ROW_INFO_HDR_BYTES;
                    assert (buffer.getUint8() == val); // EXTRA_ROW_INFO_FORMAT_OFFSET
                    for (int j = 0; j < val; j++) {
                        assert (buffer.getUint8() == val); // EXTRA_ROW_INFO_HDR_BYTES
                                                           // + i
                    }
                    break;
                default:
                    i = end;
                    break;
            }
        }
    }

    buffer.position(commonHeaderLen + postHeaderLen + headerLen);
    columnLen = (int) buffer.getPackedLong();
    this.partial = partial;
    columns = buffer.getBitmap(columnLen);

    if (header.type == UPDATE_ROWS_EVENT_V1 || header.type == UPDATE_ROWS_EVENT
        || header.type == PARTIAL_UPDATE_ROWS_EVENT) {
        changeColumns = buffer.getBitmap(columnLen);
    } else {
        changeColumns = columns;
    }

    // XXX: Don't handle buffer in another thread.
    int dataSize = buffer.limit() - buffer.position();
    rowsBuf = buffer.duplicate(dataSize);
}
 

/**
 * @see mysql-5.1.60/sql/log_event.cc - Load_log_event::copy_log_event
 */
protected final void copyLogEvent(LogBuffer buffer, final int bodyOffset, FormatDescriptionLogEvent descriptionEvent) {
    /* this is the beginning of the post-header */
    buffer.position(descriptionEvent.commonHeaderLen + L_EXEC_TIME_OFFSET);

    execTime = buffer.getUint32(); // L_EXEC_TIME_OFFSET
    skipLines = (int) buffer.getUint32(); // L_SKIP_LINES_OFFSET
    final int tableNameLen = buffer.getUint8(); // L_TBL_LEN_OFFSET
    final int dbLen = buffer.getUint8(); // L_DB_LEN_OFFSET
    numFields = (int) buffer.getUint32(); // L_NUM_FIELDS_OFFSET

    buffer.position(bodyOffset);
    /*
     * Sql_ex.init() on success returns the pointer to the first byte after
     * the sql_ex structure, which is the start of field lengths array.
     */
    if (header.type != LOAD_EVENT /* use_new_format */) {
        /*
         * The code below assumes that buf will not disappear from under our
         * feet during the lifetime of the event. This assumption holds true
         * in the slave thread if the log is in new format, but is not the
         * case when we have old format because we will be reusing net
         * buffer to read the actual file before we write out the
         * Create_file event.
         */
        fieldTerm = buffer.getString();
        enclosed = buffer.getString();
        lineTerm = buffer.getString();
        lineStart = buffer.getString();
        escaped = buffer.getString();
        optFlags = buffer.getInt8();
        emptyFlags = 0;
    } else {
        fieldTerm = buffer.getFixString(1);
        enclosed = buffer.getFixString(1);
        lineTerm = buffer.getFixString(1);
        lineStart = buffer.getFixString(1);
        escaped = buffer.getFixString(1);
        optFlags = buffer.getUint8();
        emptyFlags = buffer.getUint8();

        if ((emptyFlags & FIELD_TERM_EMPTY) != 0) fieldTerm = null;
        if ((emptyFlags & ENCLOSED_EMPTY) != 0) enclosed = null;
        if ((emptyFlags & LINE_TERM_EMPTY) != 0) lineTerm = null;
        if ((emptyFlags & LINE_START_EMPTY) != 0) lineStart = null;
        if ((emptyFlags & ESCAPED_EMPTY) != 0) escaped = null;
    }

    final int fieldLenPos = buffer.position();
    buffer.forward(numFields);
    fields = new String[numFields];
    for (int i = 0; i < numFields; i++) {
        final int fieldLen = buffer.getUint8(fieldLenPos + i);
        fields[i] = buffer.getFixString(fieldLen + 1);
    }

    table = buffer.getFixString(tableNameLen + 1);
    db = buffer.getFixString(dbLen + 1);

    // null termination is accomplished by the caller
    final int from = buffer.position();
    final int end = from + buffer.limit();
    int found = from;
    for (; (found < end) && buffer.getInt8(found) != '\0'; found++)
        /* empty loop */;
    fname = buffer.getString(found);
    buffer.forward(1); // The + 1 is for \0 terminating fname
}
 

public UserVarLogEvent(LogHeader header, LogBuffer buffer, FormatDescriptionLogEvent descriptionEvent)
                                                                                                      throws IOException{
    super(header);

    /* The Post-Header is empty. The Variable Data part begins immediately. */
    buffer.position(descriptionEvent.commonHeaderLen + descriptionEvent.postHeaderLen[USER_VAR_EVENT - 1]);
    final int nameLen = (int) buffer.getUint32();
    name = buffer.getFixString(nameLen); // UV_NAME_LEN_SIZE
    isNull = (0 != buffer.getInt8());

    if (isNull) {
        type = STRING_RESULT;
        charsetNumber = 63; /* binary */
        value = null;
    } else {
        type = buffer.getInt8(); // UV_VAL_IS_NULL
        charsetNumber = (int) buffer.getUint32(); // buf + UV_VAL_TYPE_SIZE
        final int valueLen = (int) buffer.getUint32(); // buf +
                                                       // UV_CHARSET_NUMBER_SIZE
        final int limit = buffer.limit(); /* for restore */
        buffer.limit(buffer.position() + valueLen);

        /* @see User_var_log_event::print */
        switch (type) {
            case REAL_RESULT:
                value = Double.valueOf(buffer.getDouble64()); // float8get
                break;
            case INT_RESULT:
                if (valueLen == 8) value = Long.valueOf(buffer.getLong64()); // !uint8korr
                else if (valueLen == 4) value = Long.valueOf(buffer.getUint32());
                else throw new IOException("Error INT_RESULT length: " + valueLen);
                break;
            case DECIMAL_RESULT:
                final int precision = buffer.getInt8();
                final int scale = buffer.getInt8();
                value = buffer.getDecimal(precision, scale); // bin2decimal
                break;
            case STRING_RESULT:
                String charsetName = CharsetConversion.getJavaCharset(charsetNumber);
                value = buffer.getFixString(valueLen, charsetName);
                break;
            case ROW_RESULT:
                // this seems to be banned in MySQL altogether
                throw new IOException("ROW_RESULT is unsupported");
            default:
                value = null;
                break;
        }
        buffer.limit(limit);
    }
}
 

public RowsLogEvent(LogHeader header, LogBuffer buffer, FormatDescriptionLogEvent descriptionEvent, boolean partial){
    super(header);

    final int commonHeaderLen = descriptionEvent.commonHeaderLen;
    final int postHeaderLen = descriptionEvent.postHeaderLen[header.type - 1];
    int headerLen = 0;
    buffer.position(commonHeaderLen + RW_MAPID_OFFSET);
    if (postHeaderLen == 6) {
        /*
         * Master is of an intermediate source tree before 5.1.4. Id is 4
         * bytes
         */
        tableId = buffer.getUint32();
    } else {
        tableId = buffer.getUlong48(); // RW_FLAGS_OFFSET
    }
    flags = buffer.getUint16();

    if (postHeaderLen == FormatDescriptionLogEvent.ROWS_HEADER_LEN_V2) {
        headerLen = buffer.getUint16();
        headerLen -= 2;
        int start = buffer.position();
        int end = start + headerLen;
        for (int i = start; i < end;) {
            switch (buffer.getUint8(i++)) {
                case RW_V_EXTRAINFO_TAG:
                    // int infoLen = buffer.getUint8();
                    buffer.position(i + EXTRA_ROW_INFO_LEN_OFFSET);
                    int checkLen = buffer.getUint8(); // EXTRA_ROW_INFO_LEN_OFFSET
                    int val = checkLen - EXTRA_ROW_INFO_HDR_BYTES;
                    assert (buffer.getUint8() == val); // EXTRA_ROW_INFO_FORMAT_OFFSET
                    for (int j = 0; j < val; j++) {
                        assert (buffer.getUint8() == val); // EXTRA_ROW_INFO_HDR_BYTES
                                                           // + i
                    }
                    break;
                default:
                    i = end;
                    break;
            }
        }
    }

    buffer.position(commonHeaderLen + postHeaderLen + headerLen);
    columnLen = (int) buffer.getPackedLong();
    this.partial = partial;
    columns = buffer.getBitmap(columnLen);

    if (header.type == UPDATE_ROWS_EVENT_V1 || header.type == UPDATE_ROWS_EVENT
        || header.type == PARTIAL_UPDATE_ROWS_EVENT) {
        changeColumns = buffer.getBitmap(columnLen);
    } else {
        changeColumns = columns;
    }

    // XXX: Don't handle buffer in another thread.
    int dataSize = buffer.limit() - buffer.position();
    rowsBuf = buffer.duplicate(dataSize);
}
 

/**
 * @see mysql-5.1.60/sql/log_event.cc - Load_log_event::copy_log_event
 */
protected final void copyLogEvent(LogBuffer buffer, final int bodyOffset, FormatDescriptionLogEvent descriptionEvent) {
    /* this is the beginning of the post-header */
    buffer.position(descriptionEvent.commonHeaderLen + L_EXEC_TIME_OFFSET);

    execTime = buffer.getUint32(); // L_EXEC_TIME_OFFSET
    skipLines = (int) buffer.getUint32(); // L_SKIP_LINES_OFFSET
    final int tableNameLen = buffer.getUint8(); // L_TBL_LEN_OFFSET
    final int dbLen = buffer.getUint8(); // L_DB_LEN_OFFSET
    numFields = (int) buffer.getUint32(); // L_NUM_FIELDS_OFFSET

    buffer.position(bodyOffset);
    /*
     * Sql_ex.init() on success returns the pointer to the first byte after
     * the sql_ex structure, which is the start of field lengths array.
     */
    if (header.type != LOAD_EVENT /* use_new_format */) {
        /*
         * The code below assumes that buf will not disappear from under our
         * feet during the lifetime of the event. This assumption holds true
         * in the slave thread if the log is in new format, but is not the
         * case when we have old format because we will be reusing net
         * buffer to read the actual file before we write out the
         * Create_file event.
         */
        fieldTerm = buffer.getString();
        enclosed = buffer.getString();
        lineTerm = buffer.getString();
        lineStart = buffer.getString();
        escaped = buffer.getString();
        optFlags = buffer.getInt8();
        emptyFlags = 0;
    } else {
        fieldTerm = buffer.getFixString(1);
        enclosed = buffer.getFixString(1);
        lineTerm = buffer.getFixString(1);
        lineStart = buffer.getFixString(1);
        escaped = buffer.getFixString(1);
        optFlags = buffer.getUint8();
        emptyFlags = buffer.getUint8();

        if ((emptyFlags & FIELD_TERM_EMPTY) != 0) fieldTerm = null;
        if ((emptyFlags & ENCLOSED_EMPTY) != 0) enclosed = null;
        if ((emptyFlags & LINE_TERM_EMPTY) != 0) lineTerm = null;
        if ((emptyFlags & LINE_START_EMPTY) != 0) lineStart = null;
        if ((emptyFlags & ESCAPED_EMPTY) != 0) escaped = null;
    }

    final int fieldLenPos = buffer.position();
    buffer.forward(numFields);
    fields = new String[numFields];
    for (int i = 0; i < numFields; i++) {
        final int fieldLen = buffer.getUint8(fieldLenPos + i);
        fields[i] = buffer.getFixString(fieldLen + 1);
    }

    table = buffer.getFixString(tableNameLen + 1);
    db = buffer.getFixString(dbLen + 1);

    // null termination is accomplished by the caller
    final int from = buffer.position();
    final int end = from + buffer.limit();
    int found = from;
    for (; (found < end) && buffer.getInt8(found) != '\0'; found++)
        /* empty loop */;
    fname = buffer.getString(found);
    buffer.forward(1); // The + 1 is for \0 terminating fname
}
 

public UserVarLogEvent(LogHeader header, LogBuffer buffer, FormatDescriptionLogEvent descriptionEvent)
                                                                                                      throws IOException{
    super(header);

    /* The Post-Header is empty. The Variable Data part begins immediately. */
    buffer.position(descriptionEvent.commonHeaderLen + descriptionEvent.postHeaderLen[USER_VAR_EVENT - 1]);
    final int nameLen = (int) buffer.getUint32();
    name = buffer.getFixString(nameLen); // UV_NAME_LEN_SIZE
    isNull = (0 != buffer.getInt8());

    if (isNull) {
        type = STRING_RESULT;
        charsetNumber = 63; /* binary */
        value = null;
    } else {
        type = buffer.getInt8(); // UV_VAL_IS_NULL
        charsetNumber = (int) buffer.getUint32(); // buf + UV_VAL_TYPE_SIZE
        final int valueLen = (int) buffer.getUint32(); // buf +
                                                       // UV_CHARSET_NUMBER_SIZE
        final int limit = buffer.limit(); /* for restore */
        buffer.limit(buffer.position() + valueLen);

        /* @see User_var_log_event::print */
        switch (type) {
            case REAL_RESULT:
                value = Double.valueOf(buffer.getDouble64()); // float8get
                break;
            case INT_RESULT:
                if (valueLen == 8) value = Long.valueOf(buffer.getLong64()); // !uint8korr
                else if (valueLen == 4) value = Long.valueOf(buffer.getUint32());
                else throw new IOException("Error INT_RESULT length: " + valueLen);
                break;
            case DECIMAL_RESULT:
                final int precision = buffer.getInt8();
                final int scale = buffer.getInt8();
                value = buffer.getDecimal(precision, scale); // bin2decimal
                break;
            case STRING_RESULT:
                String charsetName = CharsetConversion.getJavaCharset(charsetNumber);
                value = buffer.getFixString(valueLen, charsetName);
                break;
            case ROW_RESULT:
                // this seems to be banned in MySQL altogether
                throw new IOException("ROW_RESULT is unsupported");
            default:
                value = null;
                break;
        }
        buffer.limit(limit);
    }
}