| /* |
| * Copyright 2015 Open Networking Laboratory |
| * |
| * 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. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| package org.onosproject.store.ecmap; |
| |
| import org.apache.commons.lang3.mutable.MutableBoolean; |
| import org.mapdb.DB; |
| import org.mapdb.DBMaker; |
| import org.mapdb.Hasher; |
| import org.mapdb.Serializer; |
| import org.onosproject.store.Timestamp; |
| import org.onosproject.store.impl.Timestamped; |
| import org.onosproject.store.serializers.KryoSerializer; |
| |
| import java.io.File; |
| import java.util.Map; |
| import java.util.concurrent.ExecutorService; |
| |
| import static com.google.common.base.Preconditions.checkNotNull; |
| |
| /** |
| * MapDB based implementation of a persistent store. |
| */ |
| class MapDbPersistentStore<K, V> implements PersistentStore<K, V> { |
| |
| private final ExecutorService executor; |
| private final KryoSerializer serializer; |
| |
| private final DB database; |
| |
| private final Map<byte[], byte[]> items; |
| private final Map<byte[], byte[]> tombstones; |
| |
| /** |
| * Creates a new MapDB based persistent store. |
| * |
| * @param filename filename of the database on disk |
| * @param executor executor to use for tasks that write to the disk |
| * @param serializer serializer for keys and values |
| */ |
| MapDbPersistentStore(String filename, ExecutorService executor, |
| KryoSerializer serializer) { |
| this.executor = checkNotNull(executor); |
| this.serializer = checkNotNull(serializer); |
| |
| File databaseFile = new File(filename); |
| |
| database = DBMaker.newFileDB(databaseFile).make(); |
| |
| items = database.createHashMap("items") |
| .keySerializer(Serializer.BYTE_ARRAY) |
| .valueSerializer(Serializer.BYTE_ARRAY) |
| .hasher(Hasher.BYTE_ARRAY) |
| .makeOrGet(); |
| |
| tombstones = database.createHashMap("tombstones") |
| .keySerializer(Serializer.BYTE_ARRAY) |
| .valueSerializer(Serializer.BYTE_ARRAY) |
| .hasher(Hasher.BYTE_ARRAY) |
| .makeOrGet(); |
| } |
| |
| @Override |
| public void readInto(Map<K, Timestamped<V>> items, Map<K, Timestamp> tombstones) { |
| this.items.forEach((keyBytes, valueBytes) -> |
| items.put(serializer.decode(keyBytes), |
| serializer.decode(valueBytes))); |
| |
| this.tombstones.forEach((keyBytes, valueBytes) -> |
| tombstones.put(serializer.decode(keyBytes), |
| serializer.decode(valueBytes))); |
| } |
| |
| @Override |
| public void put(K key, V value, Timestamp timestamp) { |
| executor.submit(() -> putInternal(key, value, timestamp)); |
| } |
| |
| private void putInternal(K key, V value, Timestamp timestamp) { |
| byte[] keyBytes = serializer.encode(key); |
| byte[] removedBytes = tombstones.get(keyBytes); |
| |
| Timestamp removed = removedBytes == null ? null : |
| serializer.decode(removedBytes); |
| if (removed != null && removed.isNewerThan(timestamp)) { |
| return; |
| } |
| |
| final MutableBoolean updated = new MutableBoolean(false); |
| |
| items.compute(keyBytes, (k, existingBytes) -> { |
| Timestamped<V> existing = existingBytes == null ? null : |
| serializer.decode(existingBytes); |
| if (existing != null && existing.isNewerThan(timestamp)) { |
| updated.setFalse(); |
| return existingBytes; |
| } else { |
| updated.setTrue(); |
| return serializer.encode(new Timestamped<>(value, timestamp)); |
| } |
| }); |
| |
| boolean success = updated.booleanValue(); |
| |
| if (success && removed != null) { |
| tombstones.remove(keyBytes, removedBytes); |
| } |
| |
| database.commit(); |
| } |
| |
| @Override |
| public void remove(K key, Timestamp timestamp) { |
| executor.submit(() -> removeInternal(key, timestamp)); |
| } |
| |
| private void removeInternal(K key, Timestamp timestamp) { |
| byte[] keyBytes = serializer.encode(key); |
| |
| final MutableBoolean updated = new MutableBoolean(false); |
| |
| items.compute(keyBytes, (k, existingBytes) -> { |
| Timestamp existing = existingBytes == null ? null : |
| serializer.decode(existingBytes); |
| if (existing != null && existing.isNewerThan(timestamp)) { |
| updated.setFalse(); |
| return existingBytes; |
| } else { |
| updated.setTrue(); |
| // remove from items map |
| return null; |
| } |
| }); |
| |
| if (!updated.booleanValue()) { |
| return; |
| } |
| |
| byte[] timestampBytes = serializer.encode(timestamp); |
| byte[] removedBytes = tombstones.get(keyBytes); |
| |
| Timestamp removedTimestamp = removedBytes == null ? null : |
| serializer.decode(removedBytes); |
| if (removedTimestamp == null) { |
| tombstones.putIfAbsent(keyBytes, timestampBytes); |
| } else if (timestamp.isNewerThan(removedTimestamp)) { |
| tombstones.replace(keyBytes, removedBytes, timestampBytes); |
| } |
| |
| database.commit(); |
| } |
| |
| } |