Examples with Tuple com.evolvedbinary.j8fu.tuple.Tuple.Tuple used on opensource projects

Example 1 with Tuple

use of com.evolvedbinary.j8fu.tuple.Tuple.Tuple in project exist by eXist-db.

the class BlobStoreImpl method add.

@Override
public Tuple2<BlobId, Long> add(final Txn transaction, final InputStream is) throws IOException {
    if (state.get() != State.OPEN) {
        throw new IOException("Blob Store is not open!");
    }
    // stage the BLOB file
    final Tuple3<Path, Long, MessageDigest> staged = stage(is);
    final BlobVacuum.RequestDeleteStagedBlobFile requestDeleteStagedBlobFile = new BlobVacuum.RequestDeleteStagedBlobFile(stagingDir, staged._1.getFileName().toString());
    // register a callback to cleanup the staged BLOB file ONLY after commit+checkpoint
    final JournalManager journalManager = database.getJournalManager().orElse(null);
    if (journalManager != null) {
        final DeleteStagedBlobFile cleanupStagedBlob = new DeleteStagedBlobFile(vacuumQueue, requestDeleteStagedBlobFile);
        journalManager.listen(cleanupStagedBlob);
        transaction.registerListener(cleanupStagedBlob);
    }
    final BlobId blobId = new BlobId(staged._3.getValue());
    // if the blob entry does not exist, we exclusively compute it as STAGED.
    BlobReference blobReference = references.computeIfAbsent(blobId, k -> new BlobReference(STAGED));
    try {
        while (true) {
            if (blobReference.count.compareAndSet(STAGED, PROMOTING)) {
                // write journal entries to the WAL
                if (journalManager != null) {
                    try {
                        journalManager.journal(new StoreBlobFileLoggable(transaction.getId(), blobId, staged._1.getFileName().toString()));
                        journalManager.journal(new UpdateBlobRefCountLoggable(transaction.getId(), blobId, 0, 1));
                        // force WAL entries to disk!
                        journalManager.flush(true, true);
                    } catch (final JournalException e) {
                        references.remove(blobId);
                        throw new IOException(e);
                    }
                }
                // promote the staged blob
                promote(staged);
                if (journalManager == null) {
                    // no journal (or recovery)... so go ahead and schedule cleanup of the staged blob file
                    enqueueVacuum(vacuumQueue, requestDeleteStagedBlobFile);
                }
                // schedule disk persist of the new value
                persistQueue.put(Tuple(blobId, blobReference, 1));
                // update memory with the new value
                blobReference.count.set(1);
                // done!
                return Tuple(blobId, staged._2);
            }
            final int count = blobReference.count.get();
            // guard against a concurrent #add or #remove
            if (count == PROMOTING || count == UPDATING_COUNT) {
                // spin whilst another thread promotes the blob, or updates the reference count
                // sleep a small time to save CPU
                Thread.sleep(10);
                continue;
            }
            // i.e. wait for the deletion of the blob to complete, and then we can add the blob again
            if (count == DELETING) {
                blobReference = references.computeIfAbsent(blobId, k -> new BlobReference(STAGED));
                // loop again
                continue;
            }
            // only increment the blob reference if the blob is active!
            if (count >= 0 && blobReference.count.compareAndSet(count, UPDATING_COUNT)) {
                // NOTE: we are the only thread that can be in this branch for the blobId
                final int newCount = count + 1;
                // write journal entries to the WAL
                if (journalManager != null) {
                    try {
                        journalManager.journal(new UpdateBlobRefCountLoggable(transaction.getId(), blobId, count, newCount));
                        // force WAL entries to disk!
                        journalManager.flush(true, true);
                    } catch (final JournalException e) {
                        // restore the state of the blobReference first!
                        blobReference.count.set(count);
                        throw new IOException(e);
                    }
                }
                // persist the new value
                persistQueue.put(Tuple(blobId, blobReference, newCount));
                // update memory with the new value, and release other spinning threads
                blobReference.count.set(newCount);
                // done!
                return Tuple(blobId, staged._2);
            }
        }
    } catch (final InterruptedException e) {
        // thrown by persistQueue.put or Thread.sleep
        Thread.currentThread().interrupt();
        throw new IOException(e);
    }
}