| /** |
| * 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.hadoop.hdfs.server.namenode; |
| |
| import java.io.IOException; |
| import java.util.Collection; |
| |
| import org.apache.hadoop.hdfs.server.protocol.JournalInfo; |
| import org.apache.hadoop.hdfs.server.protocol.NamenodeRegistration; |
| import org.apache.hadoop.hdfs.server.protocol.NamespaceInfo; |
| |
| /** |
| * A JournalManager implementation that uses RPCs to log transactions |
| * to a BackupNode. |
| */ |
| class BackupJournalManager implements JournalManager { |
| private final NamenodeRegistration bnReg; |
| private final JournalInfo journalInfo; |
| |
| BackupJournalManager(NamenodeRegistration bnReg, |
| NamenodeRegistration nnReg) { |
| journalInfo = new JournalInfo(nnReg.getLayoutVersion(), |
| nnReg.getClusterID(), nnReg.getNamespaceID()); |
| this.bnReg = bnReg; |
| } |
| |
| @Override |
| public void format(NamespaceInfo nsInfo) { |
| // format() should only get called at startup, before any BNs |
| // can register with the NN. |
| throw new UnsupportedOperationException( |
| "BackupNode journal should never get formatted"); |
| } |
| |
| @Override |
| public boolean hasSomeData() { |
| throw new UnsupportedOperationException(); |
| } |
| |
| |
| @Override |
| public EditLogOutputStream startLogSegment(long txId) throws IOException { |
| EditLogBackupOutputStream stm = new EditLogBackupOutputStream(bnReg, |
| journalInfo); |
| stm.startLogSegment(txId); |
| return stm; |
| } |
| |
| @Override |
| public void finalizeLogSegment(long firstTxId, long lastTxId) |
| throws IOException { |
| } |
| |
| @Override |
| public void setOutputBufferCapacity(int size) { |
| } |
| |
| @Override |
| public void purgeLogsOlderThan(long minTxIdToKeep) |
| throws IOException { |
| } |
| |
| @Override |
| public void selectInputStreams(Collection<EditLogInputStream> streams, |
| long fromTxnId, boolean inProgressOk) { |
| // This JournalManager is never used for input. Therefore it cannot |
| // return any transactions |
| } |
| |
| @Override |
| public void recoverUnfinalizedSegments() throws IOException { |
| } |
| |
| @Override |
| public void close() throws IOException {} |
| |
| public boolean matchesRegistration(NamenodeRegistration bnReg) { |
| return bnReg.getAddress().equals(this.bnReg.getAddress()); |
| } |
| |
| @Override |
| public String toString() { |
| return "BackupJournalManager"; |
| } |
| } |