diff options
Diffstat (limited to 'framework/src/onos/core/store/dist/src/main/java/org/onosproject/store/consistent/impl/DefaultTransactionalMap.java')
| -rw-r--r-- | framework/src/onos/core/store/dist/src/main/java/org/onosproject/store/consistent/impl/DefaultTransactionalMap.java | 204 |
1 files changed, 204 insertions, 0 deletions
diff --git a/framework/src/onos/core/store/dist/src/main/java/org/onosproject/store/consistent/impl/DefaultTransactionalMap.java b/framework/src/onos/core/store/dist/src/main/java/org/onosproject/store/consistent/impl/DefaultTransactionalMap.java new file mode 100644 index 00000000..ade70335 --- /dev/null +++ b/framework/src/onos/core/store/dist/src/main/java/org/onosproject/store/consistent/impl/DefaultTransactionalMap.java @@ -0,0 +1,204 @@ +/* + * 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.consistent.impl; + +import java.util.List; +import java.util.Map; +import java.util.Set; + +import org.onlab.util.HexString; +import org.onosproject.store.service.ConsistentMap; +import org.onosproject.store.service.DatabaseUpdate; +import org.onosproject.store.service.Serializer; +import org.onosproject.store.service.TransactionContext; +import org.onosproject.store.service.TransactionalMap; +import org.onosproject.store.service.Versioned; + +import static com.google.common.base.Preconditions.*; + +import com.google.common.base.Objects; +import com.google.common.cache.CacheBuilder; +import com.google.common.cache.CacheLoader; +import com.google.common.cache.LoadingCache; +import com.google.common.collect.Lists; +import com.google.common.collect.Maps; +import com.google.common.collect.Sets; + +/** + * Default Transactional Map implementation that provides a repeatable reads + * transaction isolation level. + * + * @param <K> key type + * @param <V> value type. + */ +public class DefaultTransactionalMap<K, V> implements TransactionalMap<K, V> { + + private final TransactionContext txContext; + private static final String TX_CLOSED_ERROR = "Transaction is closed"; + private final ConsistentMap<K, V> backingMap; + private final String name; + private final Serializer serializer; + private final Map<K, Versioned<V>> readCache = Maps.newConcurrentMap(); + private final Map<K, V> writeCache = Maps.newConcurrentMap(); + private final Set<K> deleteSet = Sets.newConcurrentHashSet(); + + private static final String ERROR_NULL_VALUE = "Null values are not allowed"; + private static final String ERROR_NULL_KEY = "Null key is not allowed"; + + private final LoadingCache<K, String> keyCache = CacheBuilder.newBuilder() + .softValues() + .build(new CacheLoader<K, String>() { + + @Override + public String load(K key) { + return HexString.toHexString(serializer.encode(key)); + } + }); + + protected K dK(String key) { + return serializer.decode(HexString.fromHexString(key)); + } + + public DefaultTransactionalMap( + String name, + ConsistentMap<K, V> backingMap, + TransactionContext txContext, + Serializer serializer) { + this.name = name; + this.backingMap = backingMap; + this.txContext = txContext; + this.serializer = serializer; + } + + @Override + public V get(K key) { + checkState(txContext.isOpen(), TX_CLOSED_ERROR); + checkNotNull(key, ERROR_NULL_KEY); + if (deleteSet.contains(key)) { + return null; + } + V latest = writeCache.get(key); + if (latest != null) { + return latest; + } else { + Versioned<V> v = readCache.computeIfAbsent(key, k -> backingMap.get(k)); + return v != null ? v.value() : null; + } + } + + @Override + public V put(K key, V value) { + checkState(txContext.isOpen(), TX_CLOSED_ERROR); + checkNotNull(value, ERROR_NULL_VALUE); + + V latest = get(key); + writeCache.put(key, value); + deleteSet.remove(key); + return latest; + } + + @Override + public V remove(K key) { + checkState(txContext.isOpen(), TX_CLOSED_ERROR); + V latest = get(key); + if (latest != null) { + writeCache.remove(key); + deleteSet.add(key); + } + return latest; + } + + @Override + public boolean remove(K key, V value) { + checkState(txContext.isOpen(), TX_CLOSED_ERROR); + checkNotNull(value, ERROR_NULL_VALUE); + V latest = get(key); + if (Objects.equal(value, latest)) { + remove(key); + return true; + } + return false; + } + + @Override + public boolean replace(K key, V oldValue, V newValue) { + checkState(txContext.isOpen(), TX_CLOSED_ERROR); + checkNotNull(oldValue, ERROR_NULL_VALUE); + checkNotNull(newValue, ERROR_NULL_VALUE); + V latest = get(key); + if (Objects.equal(oldValue, latest)) { + put(key, newValue); + return true; + } + return false; + } + + @Override + public V putIfAbsent(K key, V value) { + checkState(txContext.isOpen(), TX_CLOSED_ERROR); + checkNotNull(value, ERROR_NULL_VALUE); + V latest = get(key); + if (latest == null) { + put(key, value); + } + return latest; + } + + protected List<DatabaseUpdate> prepareDatabaseUpdates() { + List<DatabaseUpdate> updates = Lists.newLinkedList(); + deleteSet.forEach(key -> { + Versioned<V> original = readCache.get(key); + if (original != null) { + updates.add(DatabaseUpdate.newBuilder() + .withMapName(name) + .withType(DatabaseUpdate.Type.REMOVE_IF_VERSION_MATCH) + .withKey(keyCache.getUnchecked(key)) + .withCurrentVersion(original.version()) + .build()); + } + }); + writeCache.forEach((key, value) -> { + Versioned<V> original = readCache.get(key); + if (original == null) { + updates.add(DatabaseUpdate.newBuilder() + .withMapName(name) + .withType(DatabaseUpdate.Type.PUT_IF_ABSENT) + .withKey(keyCache.getUnchecked(key)) + .withValue(serializer.encode(value)) + .build()); + } else { + updates.add(DatabaseUpdate.newBuilder() + .withMapName(name) + .withType(DatabaseUpdate.Type.PUT_IF_VERSION_MATCH) + .withKey(keyCache.getUnchecked(key)) + .withCurrentVersion(original.version()) + .withValue(serializer.encode(value)) + .build()); + } + }); + return updates; + } + + /** + * Discards all changes made to this transactional map. + */ + protected void rollback() { + readCache.clear(); + writeCache.clear(); + deleteSet.clear(); + } +}
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