| /** |
| * |
| * 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.bookkeeper.bookie.storage.ldb; |
| |
| import static org.apache.bookkeeper.bookie.LastAddConfirmedUpdateNotification.WATCHER_RECYCLER; |
| |
| import io.netty.buffer.ByteBuf; |
| import io.netty.buffer.Unpooled; |
| |
| import java.io.IOException; |
| import java.nio.ByteBuffer; |
| import java.util.concurrent.TimeUnit; |
| |
| import org.apache.bookkeeper.bookie.LastAddConfirmedUpdateNotification; |
| import org.apache.bookkeeper.common.util.Watchable; |
| import org.apache.bookkeeper.common.util.Watcher; |
| |
| /** |
| * This class borrows the logic from FileInfo. |
| * |
| * <p>This class is used for holding all the transient states for a given ledger. |
| */ |
| class TransientLedgerInfo extends Watchable<LastAddConfirmedUpdateNotification> implements AutoCloseable { |
| |
| static final long LEDGER_INFO_CACHING_TIME_MINUTES = 10; |
| |
| static final long NOT_ASSIGNED_LAC = Long.MIN_VALUE; |
| |
| // lac |
| private volatile long lac = NOT_ASSIGNED_LAC; |
| // request from explicit lac requests |
| private ByteBuffer explicitLac = null; |
| // is the ledger info closed? |
| private boolean isClosed; |
| |
| private final long ledgerId; |
| // reference to LedgerMetadataIndex |
| private final LedgerMetadataIndex ledgerIndex; |
| |
| private long lastAccessed; |
| |
| /** |
| * Construct an Watchable with zero watchers. |
| */ |
| public TransientLedgerInfo(long ledgerId, LedgerMetadataIndex ledgerIndex) { |
| super(WATCHER_RECYCLER); |
| this.ledgerId = ledgerId; |
| this.ledgerIndex = ledgerIndex; |
| this.lastAccessed = System.currentTimeMillis(); |
| } |
| |
| long getLastAddConfirmed() { |
| return lac; |
| } |
| |
| long setLastAddConfirmed(long lac) { |
| long lacToReturn; |
| boolean changed = false; |
| synchronized (this) { |
| if (this.lac == NOT_ASSIGNED_LAC || this.lac < lac) { |
| this.lac = lac; |
| changed = true; |
| lastAccessed = System.currentTimeMillis(); |
| } |
| lacToReturn = this.lac; |
| } |
| if (changed) { |
| notifyWatchers(lacToReturn); |
| } |
| return lacToReturn; |
| } |
| |
| synchronized boolean waitForLastAddConfirmedUpdate(long previousLAC, |
| Watcher<LastAddConfirmedUpdateNotification> watcher) throws IOException { |
| lastAccessed = System.currentTimeMillis(); |
| if ((lac != NOT_ASSIGNED_LAC && lac > previousLAC) || isClosed) { |
| return false; |
| } |
| |
| addWatcher(watcher); |
| return true; |
| } |
| |
| synchronized void cancelWaitForLastAddConfirmedUpdate(Watcher<LastAddConfirmedUpdateNotification> watcher) |
| throws IOException { |
| deleteWatcher(watcher); |
| } |
| |
| public ByteBuf getExplicitLac() { |
| ByteBuf retLac = null; |
| synchronized (this) { |
| if (explicitLac != null) { |
| retLac = Unpooled.buffer(explicitLac.capacity()); |
| explicitLac.rewind(); // copy from the beginning |
| retLac.writeBytes(explicitLac); |
| explicitLac.rewind(); |
| return retLac; |
| } |
| } |
| return retLac; |
| } |
| |
| public void setExplicitLac(ByteBuf lac) { |
| long explicitLacValue; |
| synchronized (this) { |
| if (explicitLac == null) { |
| explicitLac = ByteBuffer.allocate(lac.capacity()); |
| } |
| lac.readBytes(explicitLac); |
| explicitLac.rewind(); |
| |
| // skip the ledger id |
| explicitLac.getLong(); |
| explicitLacValue = explicitLac.getLong(); |
| explicitLac.rewind(); |
| |
| lastAccessed = System.currentTimeMillis(); |
| } |
| setLastAddConfirmed(explicitLacValue); |
| } |
| |
| boolean isStale() { |
| return (lastAccessed + TimeUnit.MINUTES.toMillis(LEDGER_INFO_CACHING_TIME_MINUTES)) < System |
| .currentTimeMillis(); |
| } |
| |
| void notifyWatchers(long lastAddConfirmed) { |
| notifyWatchers(LastAddConfirmedUpdateNotification.FUNC, lastAddConfirmed); |
| } |
| |
| @Override |
| public void close() { |
| synchronized (this) { |
| if (isClosed) { |
| return; |
| } |
| isClosed = true; |
| } |
| // notify watchers |
| notifyWatchers(Long.MAX_VALUE); |
| } |
| |
| } |