2 * Copyright 2017-2022 Open Networking Foundation and others. All rights reserved.
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
8 * http://www.apache.org/licenses/LICENSE-2.0
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
16 package io.atomix.storage.journal;
18 import io.atomix.storage.journal.JournalReader.Mode;
23 * @author <a href="http://github.com/kuujo">Jordan Halterman</a>
25 public interface Journal<E> extends AutoCloseable {
27 * Return the index of the last entry in the journal.
29 * @return the last index, or zero if there are no entries.
34 * Returns the journal writer.
36 * @return The journal writer.
38 JournalWriter<E> writer();
41 * Opens a new journal reader with {@link Mode#ALL}.
43 * @param index The index at which to start the reader.
44 * @return A new journal reader.
46 default JournalReader<E> openReader(final long index) {
47 return openReader(index, Mode.ALL);
51 * Opens a new journal reader with specified mode.
53 * @param index The index at which to start the reader.
54 * @param mode the reader mode
55 * @return A new journal reader.
57 JournalReader<E> openReader(long index, Mode mode);