Implement compact serialization for a set of discrete resources
This is for ONOS-4281.
Change-Id: I08a9fc4fd334c499c7a09d2960145743a798094e
diff --git a/core/api/src/main/java/org/onosproject/net/resource/DiscreteResourceSet.java b/core/api/src/main/java/org/onosproject/net/resource/DiscreteResourceSet.java
new file mode 100644
index 0000000..37a3f0f
--- /dev/null
+++ b/core/api/src/main/java/org/onosproject/net/resource/DiscreteResourceSet.java
@@ -0,0 +1,126 @@
+/*
+ * Copyright 2016-present 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.net.resource;
+
+import com.google.common.annotations.Beta;
+import com.google.common.collect.ImmutableSet;
+
+import java.util.Objects;
+import java.util.Optional;
+import java.util.Set;
+
+import static com.google.common.base.Preconditions.checkArgument;
+import static com.google.common.base.Preconditions.checkNotNull;
+import static com.google.common.base.Preconditions.checkState;
+
+/**
+ * Represents a set of discrete type resources.
+ * This class is intended to be used by ConsistentResourceStore though it is exposed to the public.
+ */
+@Beta
+public final class DiscreteResourceSet {
+ private final Set<DiscreteResource> values;
+ private final DiscreteResourceCodec codec;
+
+ /**
+ * Creates an instance with resources and the codec for them.
+ *
+ * @param values resources to be contained in the instance
+ * @param codec codec for the specified resources
+ * @return an instance
+ */
+ public static DiscreteResourceSet of(Set<DiscreteResource> values, DiscreteResourceCodec codec) {
+ checkNotNull(values);
+ checkNotNull(codec);
+ checkArgument(!values.isEmpty());
+
+ return new DiscreteResourceSet(ImmutableSet.copyOf(values), codec);
+ }
+
+ /**
+ * Creates the instance representing an empty resource set.
+ *
+ * @return an empty resource set
+ */
+ public static DiscreteResourceSet empty() {
+ return new DiscreteResourceSet(ImmutableSet.of(), NoOpCodec.INSTANCE);
+ }
+
+ private DiscreteResourceSet(Set<DiscreteResource> values, DiscreteResourceCodec codec) {
+ this.values = values;
+ this.codec = codec;
+ }
+
+ private DiscreteResourceSet() {
+ this.values = null;
+ this.codec = null;
+ }
+
+ /**
+ * Returns resources contained in this instance.
+ *
+ * @return resources
+ */
+ public Set<DiscreteResource> values() {
+ return values;
+ }
+
+ /**
+ * Returns the parent resource of the resources contained in this instance.
+ *
+ * @return the parent resource of the resources
+ */
+ public DiscreteResourceId parent() {
+ if (values.isEmpty()) {
+ // Dummy value avoiding null
+ return ResourceId.ROOT;
+ }
+ Optional<DiscreteResourceId> parent = values.iterator().next().id().parent();
+ checkState(parent.isPresent());
+
+ return parent.get();
+ }
+
+ /**
+ * Returns the codec for the resources contained in this instance.
+ *
+ * @return the codec for the resources
+ */
+ public DiscreteResourceCodec codec() {
+ return codec;
+ }
+
+ @Override
+ public int hashCode() {
+ return Objects.hash(values, codec);
+ }
+
+ @Override
+ public boolean equals(Object obj) {
+ if (this == obj) {
+ return true;
+ }
+
+ if (obj == null || getClass() != obj.getClass()) {
+ return false;
+ }
+
+ final DiscreteResourceSet other = (DiscreteResourceSet) obj;
+ return Objects.equals(this.values, other.values)
+ && Objects.equals(this.codec, other.codec);
+ }
+
+}
diff --git a/core/api/src/main/java/org/onosproject/net/resource/DiscreteResourceSetSerializer.java b/core/api/src/main/java/org/onosproject/net/resource/DiscreteResourceSetSerializer.java
new file mode 100644
index 0000000..ee81211
--- /dev/null
+++ b/core/api/src/main/java/org/onosproject/net/resource/DiscreteResourceSetSerializer.java
@@ -0,0 +1,78 @@
+/*
+ * Copyright 2016-present 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.net.resource;
+
+import com.esotericsoftware.kryo.Kryo;
+import com.esotericsoftware.kryo.Serializer;
+import com.esotericsoftware.kryo.io.Input;
+import com.esotericsoftware.kryo.io.Output;
+import com.google.common.annotations.Beta;
+import com.google.common.collect.DiscreteDomain;
+import com.google.common.collect.Range;
+import com.google.common.collect.TreeRangeSet;
+import org.onlab.util.ClosedOpenRange;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Set;
+import java.util.stream.Collectors;
+import java.util.stream.IntStream;
+
+/**
+ * Kryo serializer for {@link DiscreteResourceSet}.
+ */
+@Beta
+public final class DiscreteResourceSetSerializer extends Serializer<DiscreteResourceSet> {
+
+ public DiscreteResourceSetSerializer() {
+ super(false, true);
+ }
+
+ @Override
+ public void write(Kryo kryo, Output output, DiscreteResourceSet object) {
+ TreeRangeSet<Integer> rangeSet = TreeRangeSet.create();
+ object.values().stream()
+ .map(x -> object.codec().encode(x))
+ .map(Range::singleton)
+ .map(x -> x.canonical(DiscreteDomain.integers()))
+ .forEach(rangeSet::add);
+ List<ClosedOpenRange> ranges = rangeSet.asRanges().stream()
+ .map(ClosedOpenRange::of)
+ .collect(Collectors.toList());
+ kryo.writeObject(output, ranges);
+ kryo.writeClassAndObject(output, object.codec());
+ kryo.writeObject(output, object.parent());
+ }
+
+ @Override
+ public DiscreteResourceSet read(Kryo kryo, Input input, Class<DiscreteResourceSet> type) {
+ @SuppressWarnings("unchecked")
+ List<ClosedOpenRange> ranges = kryo.readObject(input, ArrayList.class);
+ DiscreteResourceCodec codec = (DiscreteResourceCodec) kryo.readClassAndObject(input);
+ DiscreteResourceId parent = kryo.readObject(input, DiscreteResourceId.class);
+
+ if (ranges.isEmpty()) {
+ return DiscreteResourceSet.empty();
+ }
+
+ Set<DiscreteResource> resources = ranges.stream()
+ .flatMapToInt(x -> IntStream.range(x.lowerBound(), x.upperBound()))
+ .mapToObj(x -> codec.decode(parent, x))
+ .collect(Collectors.toSet());
+
+ return DiscreteResourceSet.of(resources, codec);
+ }
+}
diff --git a/core/api/src/main/java/org/onosproject/net/resource/NoOpCodec.java b/core/api/src/main/java/org/onosproject/net/resource/NoOpCodec.java
new file mode 100644
index 0000000..942848b
--- /dev/null
+++ b/core/api/src/main/java/org/onosproject/net/resource/NoOpCodec.java
@@ -0,0 +1,52 @@
+/*
+ * Copyright 2016-present 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.net.resource;
+
+/**
+ * Represents no-op codec intended to used in an empty discrete resource set only.
+ * It's not supposed to be used by other classes.
+ */
+public class NoOpCodec implements DiscreteResourceCodec {
+ public static final DiscreteResourceCodec INSTANCE = new NoOpCodec();
+
+ @Override
+ public int encode(DiscreteResource resource) {
+ return 0;
+ }
+
+ @Override
+ public DiscreteResource decode(DiscreteResourceId parent, int value) {
+ return Resource.ROOT;
+ }
+
+ @Override
+ public boolean equals(Object obj) {
+ if (obj == this) {
+ return true;
+ }
+
+ if (obj == null || getClass() != obj.getClass()) {
+ return false;
+ }
+
+ return true;
+ }
+
+ @Override
+ public int hashCode() {
+ return NoOpCodec.class.hashCode();
+ }
+}