/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you 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. See the License for the
* specific language governing permissions and limitations
* under the License.
*/
package org.apache.flume.channel.file;
import java.io.File;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
import java.util.concurrent.atomic.AtomicInteger;
import com.google.common.base.Preconditions;
final class EventQueueBackingStoreFileV2 extends EventQueueBackingStoreFile {
private static final int INDEX_SIZE = 2;
private static final int INDEX_HEAD = 3;
private static final int INDEX_ACTIVE_LOG = 5;
private static final int MAX_ACTIVE_LOGS = 1024;
EventQueueBackingStoreFileV2(File checkpointFile, int capacity, String name)
throws IOException, BadCheckpointException {
super(capacity, name, checkpointFile);
Preconditions.checkArgument(capacity > 0,
"capacity must be greater than 0 " + capacity);
setLogWriteOrderID(elementsBuffer.get(INDEX_WRITE_ORDER_ID));
setSize((int) elementsBuffer.get(INDEX_SIZE));
setHead((int) elementsBuffer.get(INDEX_HEAD));
int indexMaxLog = INDEX_ACTIVE_LOG + MAX_ACTIVE_LOGS;
for (int i = INDEX_ACTIVE_LOG; i < indexMaxLog; i++) {
long nextFileCode = elementsBuffer.get(i);
if (nextFileCode != EMPTY) {
Pair<Integer, Integer> idAndCount =
deocodeActiveLogCounter(nextFileCode);
logFileIDReferenceCounts.put(idAndCount.getLeft(),
new AtomicInteger(idAndCount.getRight()));
}
}
}
@Override
protected int getVersion() {
return Serialization.VERSION_2;
}
@Override
protected void incrementFileID(int fileID) {
super.incrementFileID(fileID);
Preconditions.checkState(logFileIDReferenceCounts.size() < MAX_ACTIVE_LOGS,
"Too many active logs ");
}
private Pair<Integer, Integer> deocodeActiveLogCounter(long value) {
int fileId = (int) (value >>> 32);
int count = (int) value;
return Pair.of(fileId, count);
}
private long encodeActiveLogCounter(int fileId, int count) {
long result = fileId;
result = (long)fileId << 32;
result += (long) count;
return result;
}
@Override
protected void writeCheckpointMetaData() {
elementsBuffer.put(INDEX_SIZE, getSize());
elementsBuffer.put(INDEX_HEAD, getHead());
List<Long> fileIdAndCountEncoded = new ArrayList<Long>();
for (Integer fileId : logFileIDReferenceCounts.keySet()) {
Integer count = logFileIDReferenceCounts.get(fileId).get();
long value = encodeActiveLogCounter(fileId, count);
fileIdAndCountEncoded.add(value);
}
int emptySlots = MAX_ACTIVE_LOGS - fileIdAndCountEncoded.size();
for (int i = 0; i < emptySlots; i++) {
fileIdAndCountEncoded.add(0L);
}
for (int i = 0; i < MAX_ACTIVE_LOGS; i++) {
elementsBuffer.put(i + INDEX_ACTIVE_LOG, fileIdAndCountEncoded.get(i));
}
}
}