/**
* Copyright 2016 LinkedIn Corp. All rights reserved.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
*/
package com.github.ambry.store;
import java.util.ArrayList;
import java.util.List;
/**
* A mock journal that makes use of Journal in the background, and provides support for pausing and
* resuming the addition of entries to the backing Journal. This can be used to simulate the race
* condition of an entry getting added to the index but not yet to the journal.
*/
class MockJournal extends Journal {
private List<Offset> savedOffsets;
private List<StoreKey> savedKeys;
private List<Long> savedCrcs;
boolean paused;
public MockJournal(String dataDir, int maxEntriesToJournal, int maxEntriesToReturn) {
super(dataDir, maxEntriesToJournal, maxEntriesToReturn);
savedOffsets = new ArrayList<>();
savedKeys = new ArrayList<>();
savedCrcs = new ArrayList<>();
paused = false;
}
public void pause() {
paused = true;
}
public void resume() {
for (int i = 0; i < savedOffsets.size(); i++) {
super.addEntry(savedOffsets.get(i), savedKeys.get(i), savedCrcs.get(i));
}
paused = false;
}
@Override
public void addEntry(Offset offset, StoreKey key) {
addEntry(offset, key, null);
}
@Override
public void addEntry(Offset offset, StoreKey key, Long crc) {
if (paused) {
savedOffsets.add(offset);
savedKeys.add(key);
savedCrcs.add(crc);
} else {
super.addEntry(offset, key, crc);
}
}
}