| /* |
| * Copyright 2016 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 org.onosproject.store.service.AsyncAtomicValue; |
| import org.onosproject.store.service.AsyncConsistentMap; |
| import org.onosproject.store.service.AtomicValueEvent; |
| import org.onosproject.store.service.AtomicValueEventListener; |
| import org.onosproject.store.service.MapEvent; |
| import org.onosproject.store.service.MapEventListener; |
| import org.onosproject.store.service.Versioned; |
| |
| import java.util.Set; |
| import java.util.concurrent.CompletableFuture; |
| import java.util.concurrent.CopyOnWriteArraySet; |
| |
| /** |
| * Default implementation of {@link AsyncAtomicValue}. |
| * |
| * @param <V> value type |
| */ |
| public class DefaultAsyncAtomicValue<V> implements AsyncAtomicValue<V> { |
| |
| private final Set<AtomicValueEventListener<V>> listeners = new CopyOnWriteArraySet<>(); |
| private final AsyncConsistentMap<String, V> valueMap; |
| private final String name; |
| private final MapEventListener<String, V> mapEventListener = new InternalMapEventListener(); |
| private final MeteringAgent monitor; |
| |
| private static final String COMPONENT_NAME = "atomicValue"; |
| private static final String GET = "get"; |
| private static final String GET_AND_SET = "getAndSet"; |
| private static final String SET = "set"; |
| private static final String COMPARE_AND_SET = "compareAndSet"; |
| |
| public DefaultAsyncAtomicValue(AsyncConsistentMap<String, V> valueMap, |
| String name, |
| boolean meteringEnabled) { |
| this.valueMap = valueMap; |
| this.name = name; |
| this.monitor = new MeteringAgent(COMPONENT_NAME, name, meteringEnabled); |
| } |
| |
| @Override |
| public String name() { |
| return name; |
| } |
| |
| @Override |
| public CompletableFuture<Boolean> compareAndSet(V expect, V update) { |
| final MeteringAgent.Context newTimer = monitor.startTimer(COMPARE_AND_SET); |
| CompletableFuture<Boolean> response; |
| if (expect == null) { |
| if (update == null) { |
| response = CompletableFuture.completedFuture(true); |
| } |
| response = valueMap.putIfAbsent(name, update).thenApply(v -> v == null); |
| } else { |
| response = update == null |
| ? valueMap.remove(name, expect) |
| : valueMap.replace(name, expect, update); |
| } |
| return response.whenComplete((r, e) -> newTimer.stop(null)); |
| } |
| |
| @Override |
| public CompletableFuture<V> get() { |
| final MeteringAgent.Context newTimer = monitor.startTimer(GET); |
| return valueMap.get(name) |
| .thenApply(Versioned::valueOrNull) |
| .whenComplete((r, e) -> newTimer.stop(null)); |
| } |
| |
| @Override |
| public CompletableFuture<V> getAndSet(V value) { |
| final MeteringAgent.Context newTimer = monitor.startTimer(GET_AND_SET); |
| CompletableFuture<Versioned<V>> previousValue = value == null ? |
| valueMap.remove(name) : valueMap.put(name, value); |
| return previousValue.thenApply(Versioned::valueOrNull) |
| .whenComplete((r, e) -> newTimer.stop(null)); |
| } |
| |
| @Override |
| public CompletableFuture<Void> set(V value) { |
| final MeteringAgent.Context newTimer = monitor.startTimer(SET); |
| CompletableFuture<Void> previousValue = value == null ? |
| valueMap.remove(name).thenApply(v -> null) : valueMap.put(name, value).thenApply(v -> null); |
| return previousValue.whenComplete((r, e) -> newTimer.stop(null)); |
| } |
| |
| @Override |
| public CompletableFuture<Void> addListener(AtomicValueEventListener<V> listener) { |
| synchronized (listeners) { |
| if (listeners.add(listener)) { |
| if (listeners.size() == 1) { |
| return valueMap.addListener(mapEventListener); |
| } |
| } |
| } |
| return CompletableFuture.completedFuture(null); |
| } |
| |
| @Override |
| public CompletableFuture<Void> removeListener(AtomicValueEventListener<V> listener) { |
| synchronized (listeners) { |
| if (listeners.remove(listener)) { |
| if (listeners.size() == 0) { |
| return valueMap.removeListener(mapEventListener); |
| } |
| } |
| } |
| return CompletableFuture.completedFuture(null); |
| } |
| |
| private class InternalMapEventListener implements MapEventListener<String, V> { |
| |
| @Override |
| public void event(MapEvent<String, V> mapEvent) { |
| V newValue = mapEvent.type() == MapEvent.Type.REMOVE ? null : mapEvent.value().value(); |
| AtomicValueEvent<V> atomicValueEvent = new AtomicValueEvent<>(name, AtomicValueEvent.Type.UPDATE, newValue); |
| listeners.forEach(l -> l.event(atomicValueEvent)); |
| } |
| } |
| } |