public StoreTxLog(
StoreConfig storeConfig, File file, boolean readonly, boolean isNewFile, long firstRecordId)
throws IOException {
this.storeConfig = storeConfig;
this.entryBuffer = ByteBuffer.allocate(storeConfig.getMaxxLogEntryLength() + 1 + 4);
this.fileHeader = new StoreTxLogFileHeader();
if (!readonly) {
syncTimer = new Timer("ltsdb-dblog-sync-timer", true);
syncCallable =
new FutureTimerTask.Callable() {
@Override
public void call() throws Exception {
checkPoint();
}
};
}
if (isNewFile && file.exists()) {
throw new IOException(file + " exists already");
} else {
FileUtils.createFileIfNotExist(file);
}
fileChannel = FileUtils.newFileChannel(file, "rw");
if (isNewFile) {
// 新文件长度为头部长度
fileLength = fileHeader.getLength();
fileHeader.setFirstRecordId(firstRecordId);
fileHeader.write(fileChannel);
} else {
fileHeader.read(fileChannel);
fileLength = fileChannel.size();
lastCheckPointLength = fileLength;
}
}
public long getFirstRecordId() {
return fileHeader.getFirstRecordId();
}
public int getHeaderLength() {
return fileHeader.getLength();
}
public long getNextRecordId() {
return fileHeader.getFirstRecordId() + fileLength;
}