2 * Copyright (c) 2020 PANTHEON.tech, s.r.o. and others. All rights reserved.
4 * This program and the accompanying materials are made available under the
5 * terms of the Eclipse Public License v1.0 which accompanies this distribution,
6 * and is available at http://www.eclipse.org/legal/epl-v10.html
8 package org.opendaylight.controller.akka.segjournal;
10 import static java.util.Objects.requireNonNull;
12 import com.codahale.metrics.Histogram;
13 import org.eclipse.jdt.annotation.NonNull;
14 import org.opendaylight.controller.akka.segjournal.SegmentedJournalActor.ReplayMessages;
15 import org.opendaylight.controller.akka.segjournal.SegmentedJournalActor.WriteMessages;
16 import org.opendaylight.controller.akka.segjournal.SegmentedJournalActor.WrittenMessages;
19 * Abstraction of a data journal. This provides a unified interface towards {@link SegmentedJournalActor}, allowing
20 * specialization for various formats.
22 abstract class DataJournal {
23 // Mirrors fields from associated actor
24 final @NonNull String persistenceId;
25 private final Histogram messageSize;
27 // Tracks largest message size we have observed either during recovery or during write
28 private int largestObservedSize;
30 DataJournal(final String persistenceId, final Histogram messageSize) {
31 this.persistenceId = requireNonNull(persistenceId);
32 this.messageSize = requireNonNull(messageSize);
35 final void recordMessageSize(final int size) {
36 messageSize.update(size);
37 updateLargestSize(size);
40 final void updateLargestSize(final int size) {
41 if (size > largestObservedSize) {
42 largestObservedSize = size;
47 * Return the last sequence number completely written to the journal.
49 * @return Last written sequence number, {@code -1} if there are no in the journal.
51 abstract long lastWrittenSequenceNr();
54 * Delete all messages up to specified sequence number.
56 * @param sequenceNr Sequence number to delete to.
58 abstract void deleteTo(long sequenceNr);
61 * Delete all messages up to specified sequence number.
63 * @param sequenceNr Sequence number to compact to.
65 abstract void compactTo(long sequenceNr);
68 * Close this journal, freeing up resources associated with it.
70 abstract void close();
73 * Handle a request to replay messages.
75 * @param message Request message
76 * @param fromSequenceNr Sequence number to replay from, adjusted for deletions
78 abstract void handleReplayMessages(@NonNull ReplayMessages message, long fromSequenceNr);
81 * Handle a request to store some messages.
83 * @param message {@link WriteMessages} message
84 * @return a {@link WrittenMessages} object
86 abstract @NonNull WrittenMessages handleWriteMessages(@NonNull WriteMessages message);
89 * Flush all messages to durable storage.
91 abstract void flush();