Examples with FileRef org.apache.jena.tdb.sys.FileRef used on opensource projects

Example 1 with FileRef

use of org.apache.jena.tdb.sys.FileRef in project jena by apache.

the class JournalControl method recoverFromJournal.

/**
 * Recovery from a journal.
 *  Find if there is a commit record; if so, replay the journal to that point.
 *  Try to see if there is another commit record ...
 *  Return true if a recovery was attempted; return false if we decided no work needed.
 */
public static boolean recoverFromJournal(StorageConfig sConf, Journal jrnl) {
    if (jrnl.isEmpty())
        return false;
    for (FileRef fileRef : sConf.objectFiles.keySet()) recoverNodeDat(sConf.location, fileRef);
    long posn = 0;
    for (; ; ) {
        // Any errors indicate a partially written journal.
        // A commit was not written properly in the prepare phase.
        // e.g. JVM died half-way though writing the prepare phase data.
        // The valid journal ends at this point. Exit loop and clean up.
        long x;
        try {
            x = scanForCommit(jrnl, posn);
        } catch (TDBException ex) {
            x = -1;
        }
        if (x == -1)
            break;
        recoverSegment(jrnl, posn, x, sConf);
        posn = x;
    }
    // Sync database.
    syncAll(sConf);
    // We have replayed the journals - clean up.
    jrnl.truncate(0);
    jrnl.sync();
    return true;
}

Example 2 with FileRef

use of org.apache.jena.tdb.sys.FileRef in project jena by apache.

the class Journal method _read.

// read one entry at the channel position.
// Move position to end of read.
private JournalEntry _read() {
    header.clear();
    int lenRead = channel.read(header);
    if (lenRead == -1) {
        // probably broken file.
        throw new TDBTransactionException("Read off the end of a journal file");
    // return null;
    }
    header.rewind();
    int typeId = header.getInt();
    int len = header.getInt();
    int ref = header.getInt();
    int blockId = header.getInt();
    Adler32 adler = new Adler32();
    adler.update(header.array());
    ByteBuffer bb = ByteBuffer.allocate(len);
    lenRead = channel.read(bb);
    if (lenRead != len)
        throw new TDBTransactionException("Failed to read the journal entry: wanted " + len + " bytes, got " + lenRead);
    adler.update(bb.array());
    bb.rewind();
    // checksum
    crcTrailer.clear();
    lenRead = channel.read(crcTrailer);
    if (lenRead != SizeofCRC)
        throw new TDBTransactionException("Failed to read block checksum (got " + lenRead + " bytes, not " + SizeofCRC + ").");
    int checksum = Bytes.getInt(crcTrailer.array());
    if (checksum != (int) adler.getValue())
        throw new TDBTransactionException("Checksum error reading from the Journal.");
    JournalEntryType type = JournalEntryType.type(typeId);
    FileRef fileRef = FileRef.get(ref);
    Block block = new Block(blockId, bb);
    return new JournalEntry(type, fileRef, block);
}

Example 3 with FileRef

use of org.apache.jena.tdb.sys.FileRef in project jena by apache.

the class JournalControl method recovery.

/** Recover a base storage DatasetGraph */
public static void recovery(DatasetGraphTDB dsg) {
    if (dsg.getLocation().isMem())
        return;
    // Do we need to recover?
    Journal journal = findJournal(dsg);
    if (journal == null || journal.isEmpty())
        return;
    for (FileRef fileRef : dsg.getConfig().nodeTables.keySet()) recoverNodeDat(dsg, fileRef);
    recoverFromJournal(dsg.getConfig(), journal);
    journal.close();
    // Recovery complete.  Tidy up.  Node journal files have already been handled.
    if (journal.getFilename() != null) {
        if (FileOps.exists(journal.getFilename()))
            FileOps.delete(journal.getFilename());
    }
}