Added a AtomicValue distributed primitive.
Change-Id: I00ff165cbd9c6e4f2610af9877ff262527b7b048
diff --git a/core/api/src/main/java/org/onosproject/store/service/AtomicValue.java b/core/api/src/main/java/org/onosproject/store/service/AtomicValue.java
new file mode 100644
index 0000000..dfa0fb3
--- /dev/null
+++ b/core/api/src/main/java/org/onosproject/store/service/AtomicValue.java
@@ -0,0 +1,69 @@
+/*
+ * 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.service;
+
+/**
+ * Distributed version of java.util.concurrent.atomic.AtomicReference.
+ *
+ * @param <V> value type
+ */
+public interface AtomicValue<V> {
+
+ /**
+ * Atomically sets the value to the given updated value if the current value is equal to the expected value.
+ * <p>
+ * IMPORTANT: Equality is based on the equality of the serialized byte[] representations.
+ * <p>
+ * @param expect the expected value
+ * @param update the new value
+ * @return true if successful. false return indicates that the actual value was not equal to the expected value.
+ */
+ boolean compareAndSet(V expect, V update);
+
+ /**
+ * Gets the current value.
+ * @return current value
+ */
+ V get();
+
+ /**
+ * Atomically sets to the given value and returns the old value.
+ * @param value the new value
+ * @return previous value
+ */
+ V getAndSet(V value);
+
+ /**
+ * Sets to the given value.
+ * @param value new value
+ */
+ void set(V value);
+
+ /**
+ * Registers the specified listener to be notified whenever the atomic value is updated.
+ *
+ * @param listener listener to notify about events
+ */
+ void addListener(AtomicValueEventListener<V> listener);
+
+ /**
+ * Unregisters the specified listener such that it will no longer
+ * receive atomic value update notifications.
+ *
+ * @param listener listener to unregister
+ */
+ void removeListener(AtomicValueEventListener<V> listener);
+}
diff --git a/core/api/src/main/java/org/onosproject/store/service/AtomicValueBuilder.java b/core/api/src/main/java/org/onosproject/store/service/AtomicValueBuilder.java
new file mode 100644
index 0000000..6527b9c
--- /dev/null
+++ b/core/api/src/main/java/org/onosproject/store/service/AtomicValueBuilder.java
@@ -0,0 +1,70 @@
+/*
+ * 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.service;
+
+/**
+ * Builder for constructing new AtomicValue instances.
+ *
+ * @param <V> atomic value type
+ */
+public interface AtomicValueBuilder<V> {
+ /**
+ * Sets the name for the atomic value.
+ * <p>
+ * Each atomic value is identified by a unique name.
+ * </p>
+ * <p>
+ * Note: This is a mandatory parameter.
+ * </p>
+ *
+ * @param name name of the atomic value
+ * @return this AtomicValueBuilder for method chaining
+ */
+ AtomicValueBuilder<V> withName(String name);
+
+ /**
+ * Sets a serializer that can be used to serialize the value.
+ * <p>
+ * Note: This is a mandatory parameter.
+ * </p>
+ *
+ * @param serializer serializer
+ * @return this AtomicValueBuilder for method chaining
+ */
+ AtomicValueBuilder<V> withSerializer(Serializer serializer);
+
+ /**
+ * Creates this atomic value on the partition that spans the entire cluster.
+ * <p>
+ * When partitioning is disabled, the value state will be
+ * ephemeral and does not survive a full cluster restart.
+ * </p>
+ * <p>
+ * Note: By default partitions are enabled.
+ * </p>
+ * @return this AtomicValueBuilder for method chaining
+ */
+ AtomicValueBuilder<V> withPartitionsDisabled();
+
+ /**
+ * Builds a AtomicValue based on the configuration options
+ * supplied to this builder.
+ *
+ * @return new AtomicValue
+ * @throws java.lang.RuntimeException if a mandatory parameter is missing
+ */
+ AtomicValue<V> build();
+}
diff --git a/core/api/src/main/java/org/onosproject/store/service/AtomicValueEvent.java b/core/api/src/main/java/org/onosproject/store/service/AtomicValueEvent.java
new file mode 100644
index 0000000..226b164
--- /dev/null
+++ b/core/api/src/main/java/org/onosproject/store/service/AtomicValueEvent.java
@@ -0,0 +1,109 @@
+/*
+ * 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.service;
+
+import java.util.Objects;
+
+import com.google.common.base.MoreObjects;
+
+/**
+ * Representation of a AtomicValue update notification.
+ *
+ * @param <V> atomic value type
+ */
+public class AtomicValueEvent<V> {
+
+ /**
+ * AtomicValueEvent type.
+ */
+ public enum Type {
+
+ /**
+ * Value was updated.
+ */
+ UPDATE,
+ }
+
+ private final String name;
+ private final Type type;
+ private final V value;
+
+ /**
+ * Creates a new event object.
+ *
+ * @param name AtomicValue name
+ * @param type the type of the event
+ * @param value the new value
+ */
+ public AtomicValueEvent(String name, Type type, V value) {
+ this.name = name;
+ this.type = type;
+ this.value = value;
+ }
+
+ /**
+ * Returns the AtomicValue name.
+ *
+ * @return name of atomic value
+ */
+ public String name() {
+ return name;
+ }
+
+ /**
+ * Returns the type of the event.
+ *
+ * @return the type of the event
+ */
+ public Type type() {
+ return type;
+ }
+
+ /**
+ * Returns the new updated value.
+ *
+ * @return the value
+ */
+ public V value() {
+ return value;
+ }
+
+ @Override
+ public boolean equals(Object o) {
+ if (!(o instanceof AtomicValueEvent)) {
+ return false;
+ }
+
+ AtomicValueEvent<V> that = (AtomicValueEvent) o;
+ return Objects.equals(this.name, that.name) &&
+ Objects.equals(this.type, that.type) &&
+ Objects.equals(this.value, that.value);
+ }
+
+ @Override
+ public int hashCode() {
+ return Objects.hash(name, type, value);
+ }
+
+ @Override
+ public String toString() {
+ return MoreObjects.toStringHelper(getClass())
+ .add("name", name)
+ .add("type", type)
+ .add("value", value)
+ .toString();
+ }
+}
\ No newline at end of file
diff --git a/core/api/src/main/java/org/onosproject/store/service/AtomicValueEventListener.java b/core/api/src/main/java/org/onosproject/store/service/AtomicValueEventListener.java
new file mode 100644
index 0000000..b29d903
--- /dev/null
+++ b/core/api/src/main/java/org/onosproject/store/service/AtomicValueEventListener.java
@@ -0,0 +1,28 @@
+/*
+ * 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.service;
+
+/**
+ * Listener to be notified about updates to a AtomicValue.
+ */
+public interface AtomicValueEventListener<V> {
+ /**
+ * Reacts to the specified event.
+ *
+ * @param event the event
+ */
+ void event(AtomicValueEvent<V> event);
+}
diff --git a/core/api/src/main/java/org/onosproject/store/service/StorageService.java b/core/api/src/main/java/org/onosproject/store/service/StorageService.java
index 58ac390..9ba8780 100644
--- a/core/api/src/main/java/org/onosproject/store/service/StorageService.java
+++ b/core/api/src/main/java/org/onosproject/store/service/StorageService.java
@@ -71,6 +71,14 @@
AtomicCounterBuilder atomicCounterBuilder();
/**
+ * Creates a new AtomicValueBuilder.
+ *
+ * @param <V> atomic value type
+ * @return atomic value builder
+ */
+ <V> AtomicValueBuilder<V> atomicValueBuilder();
+
+ /**
* Creates a new transaction context builder.
*
* @return a builder for a transaction context.
diff --git a/core/store/dist/src/main/java/org/onosproject/store/consistent/impl/DatabaseManager.java b/core/store/dist/src/main/java/org/onosproject/store/consistent/impl/DatabaseManager.java
index 86f7103..d04f5c7 100644
--- a/core/store/dist/src/main/java/org/onosproject/store/consistent/impl/DatabaseManager.java
+++ b/core/store/dist/src/main/java/org/onosproject/store/consistent/impl/DatabaseManager.java
@@ -63,6 +63,7 @@
import org.onosproject.store.cluster.messaging.MessageSubject;
import org.onosproject.store.ecmap.EventuallyConsistentMapBuilderImpl;
import org.onosproject.store.service.AtomicCounterBuilder;
+import org.onosproject.store.service.AtomicValueBuilder;
import org.onosproject.store.service.ConsistentMapBuilder;
import org.onosproject.store.service.ConsistentMapException;
import org.onosproject.store.service.DistributedQueueBuilder;
@@ -383,6 +384,11 @@
}
@Override
+ public <V> AtomicValueBuilder<V> atomicValueBuilder() {
+ return new DefaultAtomicValueBuilder<>(this);
+ }
+
+ @Override
public List<MapInfo> getMapInfo() {
List<MapInfo> maps = Lists.newArrayList();
maps.addAll(getMapInfo(inMemoryDatabase));
diff --git a/core/store/dist/src/main/java/org/onosproject/store/consistent/impl/DefaultAtomicValue.java b/core/store/dist/src/main/java/org/onosproject/store/consistent/impl/DefaultAtomicValue.java
new file mode 100644
index 0000000..c13a3b8
--- /dev/null
+++ b/core/store/dist/src/main/java/org/onosproject/store/consistent/impl/DefaultAtomicValue.java
@@ -0,0 +1,115 @@
+/*
+ * 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.Set;
+import java.util.concurrent.CopyOnWriteArraySet;
+
+import org.onosproject.store.service.AtomicValue;
+import org.onosproject.store.service.AtomicValueEvent;
+import org.onosproject.store.service.AtomicValueEventListener;
+import org.onosproject.store.service.ConsistentMap;
+import org.onosproject.store.service.MapEvent;
+import org.onosproject.store.service.MapEventListener;
+import org.onosproject.store.service.Serializer;
+import org.onosproject.store.service.Versioned;
+
+/**
+ * Default implementation of AtomicValue.
+ *
+ * @param <V> value type
+ */
+public class DefaultAtomicValue<V> implements AtomicValue<V> {
+
+ private final Set<AtomicValueEventListener<V>> listeners = new CopyOnWriteArraySet<>();
+ private final ConsistentMap<String, byte[]> valueMap;
+ private final String name;
+ private final Serializer serializer;
+ private final MapEventListener<String, byte[]> mapEventListener = new InternalMapEventListener();
+
+ public DefaultAtomicValue(ConsistentMap<String, byte[]> valueMap,
+ String name,
+ Serializer serializer) {
+ this.valueMap = valueMap;
+ this.name = name;
+ this.serializer = serializer;
+ }
+
+ @Override
+ public boolean compareAndSet(V expect, V update) {
+ if (expect == null) {
+ if (update == null) {
+ return true;
+ }
+ return valueMap.putIfAbsent(name, serializer.encode(update)) == null;
+ } else {
+ if (update == null) {
+ return valueMap.remove(name, serializer.encode(expect));
+ }
+ return valueMap.replace(name, serializer.encode(expect), serializer.encode(update));
+ }
+ }
+
+ @Override
+ public V get() {
+ Versioned<byte[]> rawValue = valueMap.get(name);
+ return rawValue == null ? null : serializer.decode(rawValue.value());
+ }
+
+ @Override
+ public V getAndSet(V value) {
+ Versioned<byte[]> previousValue = value == null ?
+ valueMap.remove(name) : valueMap.put(name, serializer.encode(value));
+ return previousValue == null ? null : serializer.decode(previousValue.value());
+ }
+
+ @Override
+ public void set(V value) {
+ getAndSet(value);
+ }
+
+ @Override
+ public void addListener(AtomicValueEventListener<V> listener) {
+ synchronized (listeners) {
+ if (listeners.add(listener)) {
+ if (listeners.size() == 1) {
+ valueMap.addListener(mapEventListener);
+ }
+ }
+ }
+ }
+
+ @Override
+ public void removeListener(AtomicValueEventListener<V> listener) {
+ synchronized (listeners) {
+ if (listeners.remove(listener)) {
+ if (listeners.size() == 0) {
+ valueMap.removeListener(mapEventListener);
+ }
+ }
+ }
+ }
+
+ private class InternalMapEventListener implements MapEventListener<String, byte[]> {
+
+ @Override
+ public void event(MapEvent<String, byte[]> mapEvent) {
+ V newValue = mapEvent.type() == MapEvent.Type.REMOVE ? null : serializer.decode(mapEvent.value().value());
+ AtomicValueEvent<V> atomicValueEvent = new AtomicValueEvent<>(name, AtomicValueEvent.Type.UPDATE, newValue);
+ listeners.forEach(l -> l.event(atomicValueEvent));
+ }
+ }
+}
diff --git a/core/store/dist/src/main/java/org/onosproject/store/consistent/impl/DefaultAtomicValueBuilder.java b/core/store/dist/src/main/java/org/onosproject/store/consistent/impl/DefaultAtomicValueBuilder.java
new file mode 100644
index 0000000..a267de0
--- /dev/null
+++ b/core/store/dist/src/main/java/org/onosproject/store/consistent/impl/DefaultAtomicValueBuilder.java
@@ -0,0 +1,63 @@
+/*
+ * 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 org.onosproject.store.serializers.KryoNamespaces;
+import org.onosproject.store.service.AtomicValue;
+import org.onosproject.store.service.AtomicValueBuilder;
+import org.onosproject.store.service.ConsistentMapBuilder;
+import org.onosproject.store.service.Serializer;
+
+/**
+ * Default implementation of AtomicValueBuilder.
+ *
+ * @param <V> value type
+ */
+public class DefaultAtomicValueBuilder<V> implements AtomicValueBuilder<V> {
+
+ private Serializer serializer;
+ private String name;
+ private ConsistentMapBuilder<String, byte[]> mapBuilder;
+
+ public DefaultAtomicValueBuilder(DatabaseManager manager) {
+ mapBuilder = manager.<String, byte[]>consistentMapBuilder()
+ .withName("onos-atomic-values")
+ .withSerializer(Serializer.using(KryoNamespaces.BASIC));
+ }
+
+ @Override
+ public AtomicValueBuilder<V> withName(String name) {
+ this.name = name;
+ return this;
+ }
+
+ @Override
+ public AtomicValueBuilder<V> withSerializer(Serializer serializer) {
+ this.serializer = serializer;
+ return this;
+ }
+
+ @Override
+ public AtomicValueBuilder<V> withPartitionsDisabled() {
+ mapBuilder.withPartitionsDisabled();
+ return this;
+ }
+
+ @Override
+ public AtomicValue<V> build() {
+ return new DefaultAtomicValue<>(mapBuilder.build(), name, serializer);
+ }
+}
\ No newline at end of file