private EntryPosition findAsPerTimestampInSpecificLogFile(MysqlConnection mysqlConnection,
final Long startTimestamp,
final EntryPosition endPosition,
final String searchBinlogFile) {
final LogPosition logPosition = new LogPosition();
try {
mysqlConnection.reconnect();
// 开始遍历文件
mysqlConnection.seek(searchBinlogFile, 4L, new SinkFunction<LogEvent>() {
private LogPosition lastPosition;
public boolean sink(LogEvent event) {
EntryPosition entryPosition = null;
try {
CanalEntry.Entry entry = parseAndProfilingIfNecessary(event);
if (entry == null) {
return true;
}
String logfilename = entry.getHeader().getLogfileName();
Long logfileoffset = entry.getHeader().getLogfileOffset();
Long logposTimestamp = entry.getHeader().getExecuteTime();
if (CanalEntry.EntryType.TRANSACTIONBEGIN.equals(entry.getEntryType())) {
logger.debug("compare exit condition:{},{},{}, startTimestamp={}...", new Object[] {
logfilename, logfileoffset, logposTimestamp, startTimestamp });
// 寻找第一条记录时间戳，如果最小的一条记录都不满足条件，可直接退出
if (logposTimestamp >= startTimestamp) {
return false;
}
}
if (StringUtils.equals(endPosition.getJournalName(), logfilename)
&& endPosition.getPosition() <= (logfileoffset + event.getEventLen())) {
return false;
}
// 记录一下上一个事务结束的位置，即下一个事务的position
// position = current + data.length，代表该事务的下一条offest，避免多余的事务重复
if (CanalEntry.EntryType.TRANSACTIONEND.equals(entry.getEntryType())) {
entryPosition = new EntryPosition(logfilename, logfileoffset + event.getEventLen(),
logposTimestamp);
logger.debug("set {} to be pending start position before finding another proper one...",
entryPosition);
logPosition.setPostion(entryPosition);
}
lastPosition = buildLastPosition(entry);
} catch (Exception e) {
processError(e, lastPosition, searchBinlogFile, 4L);
}
return running;
}
});
} catch (IOException e) {
logger.error("ERROR ## findAsPerTimestampInSpecificLogFile has an error", e);
}
if (logPosition.getPostion() != null) {
return logPosition.getPostion();
} else {
return null;
}
}