Examples with ReadAheadLogChannel org.neo4j.kernel.impl.transaction.log.ReadAheadLogChannel used on opensource projects

Example 11 with ReadAheadLogChannel

use of org.neo4j.kernel.impl.transaction.log.ReadAheadLogChannel in project neo4j by neo4j.

the class RebuildFromLogs method findLastTransactionId.

private long findLastTransactionId(PhysicalLogFiles logFiles, long highestVersion) throws IOException {
    ReadableLogChannel logChannel = new ReadAheadLogChannel(PhysicalLogFile.openForVersion(logFiles, fs, highestVersion, false), NO_MORE_CHANNELS);
    long lastTransactionId = -1;
    LogEntryReader<ReadableClosablePositionAwareChannel> entryReader = new VersionAwareLogEntryReader<>();
    try (IOCursor<CommittedTransactionRepresentation> cursor = new PhysicalTransactionCursor<>(logChannel, entryReader)) {
        while (cursor.next()) {
            lastTransactionId = cursor.get().getCommitEntry().getTxId();
        }
    }
    return lastTransactionId;
}

Example 12 with ReadAheadLogChannel

use of org.neo4j.kernel.impl.transaction.log.ReadAheadLogChannel in project neo4j by neo4j.

the class LogTestUtils method filterNeostoreLogicalLog.

public static File filterNeostoreLogicalLog(FileSystemAbstraction fileSystem, File file, final LogHook<LogEntry> filter) throws IOException {
    filter.file(file);
    File tempFile = new File(file.getAbsolutePath() + ".tmp");
    fileSystem.deleteFile(tempFile);
    try (StoreChannel in = fileSystem.open(file, "r");
        StoreChannel out = fileSystem.open(tempFile, "rw")) {
        LogHeader logHeader = transferLogicalLogHeader(in, out, ByteBuffer.allocate(LOG_HEADER_SIZE));
        PhysicalLogVersionedStoreChannel outChannel = new PhysicalLogVersionedStoreChannel(out, logHeader.logVersion, logHeader.logFormatVersion);
        PhysicalLogVersionedStoreChannel inChannel = new PhysicalLogVersionedStoreChannel(in, logHeader.logVersion, logHeader.logFormatVersion);
        ReadableLogChannel inBuffer = new ReadAheadLogChannel(inChannel, LogVersionBridge.NO_MORE_CHANNELS);
        LogEntryReader<ReadableLogChannel> entryReader = new VersionAwareLogEntryReader<>();
        LogEntry entry;
        while ((entry = entryReader.readLogEntry(inBuffer)) != null) {
            if (filter.test(entry)) {
            // TODO allright, write to outBuffer
            }
        }
    }
    return tempFile;
}