org.graylog2.shared.journal.NoopJournal Maven / Gradle / Ivy
/*
* Copyright (C) 2020 Graylog, Inc.
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the Server Side Public License, version 1,
* as published by MongoDB, Inc.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* Server Side Public License for more details.
*
* You should have received a copy of the Server Side Public License
* along with this program. If not, see
* .
*/
package org.graylog2.shared.journal;
import com.google.common.util.concurrent.AbstractIdleService;
import java.util.List;
/**
* NoopJournal is used when disk journalling is turned off. In order to avoid propagating the knowledge about whether
* journalling is happening or not, we inject a no-op journal.
* Any use of this journal will throw an IllegalStateException.
*/
public class NoopJournal extends AbstractIdleService implements Journal {
@Override
public Entry createEntry(byte[] idBytes, byte[] messageBytes) {
return new Entry(idBytes, messageBytes);
}
@Override
public long write(List entries) {
throw new IllegalStateException("Invalid use of NoopJournal. Writing to this journal is always a programming error.");
}
@Override
public long write(byte[] idBytes, byte[] messageBytes) {
throw new IllegalStateException("Invalid use of NoopJournal. Writing to this journal is always a programming error.");
}
@Override
public List read(long maximumCount) {
throw new IllegalStateException("Invalid use of NoopJournal. Reading from this journal is always a programming error.");
}
@Override
public void markJournalOffsetCommitted(long offset) {
// nothing to do
}
@Override
protected void startUp() throws Exception {
// nothing to do
}
@Override
protected void shutDown() throws Exception {
// nothing to do
}
@Override
public void flush() {
// nothing to do
}
}