Introduce abstract interface for set of discrete resources

Change-Id: Iddbed1a2dd0c6ce3d7288371a47a7b0aeba46803

@@ -71,7 +71,7 @@ public class ConsistentResourceStore extends AbstractStore<ResourceEvent, Resour
 
     static final Serializer SERIALIZER = Serializer.using(
             Arrays.asList(KryoNamespaces.API),
-            DiscreteResources.class,
+            NonEncodableDiscreteResources.class,
             ContinuousResourceAllocation.class);
 
     // TODO: We should provide centralized values for this

@@ -15,99 +15,31 @@
  */
 package org.onosproject.store.resource.impl;
 
-import com.google.common.base.MoreObjects;
-import com.google.common.collect.Sets;
 import org.onosproject.net.resource.DiscreteResource;
 import org.onosproject.net.resource.DiscreteResourceId;
-import org.onosproject.net.resource.Resources;
 
-import java.util.LinkedHashSet;
 import java.util.List;
-import java.util.Objects;
 import java.util.Optional;
 import java.util.Set;
 
-final class DiscreteResources {
-    private final Set<DiscreteResource> values;
-
+interface DiscreteResources {
     static DiscreteResources empty() {
-        return new DiscreteResources();
-    }
-
-    private DiscreteResources() {
-        this.values = new LinkedHashSet<>();
-    }
-
-    DiscreteResources(List<DiscreteResource> values) {
-        this.values = new LinkedHashSet<>(values);
+        return NonEncodableDiscreteResources.empty();
     }
 
-    private DiscreteResources(Set<DiscreteResource> values) {
-        this.values = values;
-    }
+    Optional<DiscreteResource> lookup(DiscreteResourceId id);
 
-    Optional<DiscreteResource> lookup(DiscreteResourceId id) {
-        DiscreteResource resource = Resources.discrete(id).resource();
-        if (values.contains(resource)) {
-            return Optional.of(resource);
-        } else {
-            return Optional.empty();
-        }
-    }
+    DiscreteResources difference(DiscreteResources other);
 
-    DiscreteResources difference(DiscreteResources other) {
-        return new DiscreteResources(Sets.difference(this.values, other.values));
-    }
-
-    boolean isEmpty() {
-        return values.isEmpty();
-    }
+    boolean isEmpty();
 
-    boolean containsAny(List<DiscreteResource> other) {
-        return other.stream().anyMatch(values::contains);
-    }
+    boolean containsAny(List<DiscreteResource> other);
 
     // returns a new instance, not mutate the current instance
-    DiscreteResources add(DiscreteResources other) {
-        Set<DiscreteResource> newValues = new LinkedHashSet<>(this.values);
-        newValues.addAll(other.values);
-        return new DiscreteResources(newValues);
-    }
+    DiscreteResources add(DiscreteResources other);
 
     // returns a new instance, not mutate the current instance
-    DiscreteResources remove(List<DiscreteResource> removed) {
-        Set<DiscreteResource> newValues = new LinkedHashSet<>(this.values);
-        newValues.removeAll(removed);
-        return new DiscreteResources(newValues);
-    }
-
-    Set<DiscreteResource> values() {
-        // breaks immutability, but intentionally returns the field
-        // because this class is transient
-        return values;
-    }
+    DiscreteResources remove(List<DiscreteResource> removed);
 
-    @Override
-    public int hashCode() {
-        return Objects.hash(values);
-    }
-
-    @Override
-    public boolean equals(Object obj) {
-        if (this == obj) {
-            return true;
-        }
-        if (obj == null || getClass() != obj.getClass()) {
-            return false;
-        }
-        final DiscreteResources other = (DiscreteResources) obj;
-        return Objects.equals(this.values, other.values);
-    }
-
-    @Override
-    public String toString() {
-        return MoreObjects.toStringHelper(this)
-                .add("values", values)
-                .toString();
-    }
+    Set<DiscreteResource> values();
 }

+/*
+ * 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.store.resource.impl;
+
+import com.google.common.base.MoreObjects;
+import com.google.common.collect.Sets;
+import org.onosproject.net.resource.DiscreteResource;
+import org.onosproject.net.resource.DiscreteResourceId;
+import org.onosproject.net.resource.Resources;
+
+import java.util.LinkedHashSet;
+import java.util.List;
+import java.util.Objects;
+import java.util.Optional;
+import java.util.Set;
+
+final class NonEncodableDiscreteResources implements DiscreteResources {
+    private final Set<DiscreteResource> values;
+
+    static NonEncodableDiscreteResources empty() {
+        return new NonEncodableDiscreteResources();
+    }
+
+    private NonEncodableDiscreteResources() {
+        this.values = new LinkedHashSet<>();
+    }
+
+    NonEncodableDiscreteResources(List<DiscreteResource> values) {
+        this.values = new LinkedHashSet<>(values);
+    }
+
+    private NonEncodableDiscreteResources(Set<DiscreteResource> values) {
+        this.values = values;
+    }
+
+    @Override
+    public Optional<DiscreteResource> lookup(DiscreteResourceId id) {
+        DiscreteResource resource = Resources.discrete(id).resource();
+        if (values.contains(resource)) {
+            return Optional.of(resource);
+        } else {
+            return Optional.empty();
+        }
+    }
+
+    @Override
+    public DiscreteResources difference(DiscreteResources other) {
+        return new NonEncodableDiscreteResources(Sets.difference(this.values, other.values()));
+    }
+
+    @Override
+    public boolean isEmpty() {
+        return values.isEmpty();
+    }
+
+    @Override
+    public boolean containsAny(List<DiscreteResource> other) {
+        return other.stream().anyMatch(values::contains);
+    }
+
+    // returns a new instance, not mutate the current instance
+    @Override
+    public DiscreteResources add(DiscreteResources other) {
+        Set<DiscreteResource> newValues = new LinkedHashSet<>(this.values);
+        newValues.addAll(other.values());
+        return new NonEncodableDiscreteResources(newValues);
+    }
+
+    // returns a new instance, not mutate the current instance
+    @Override
+    public DiscreteResources remove(List<DiscreteResource> removed) {
+        Set<DiscreteResource> newValues = new LinkedHashSet<>(this.values);
+        newValues.removeAll(removed);
+        return new NonEncodableDiscreteResources(newValues);
+    }
+
+    @Override
+    public Set<DiscreteResource> values() {
+        // breaks immutability, but intentionally returns the field
+        // because this class is transient
+        return values;
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hash(values);
+    }
+
+    @Override
+    public boolean equals(Object obj) {
+        if (this == obj) {
+            return true;
+        }
+        if (obj == null || getClass() != obj.getClass()) {
+            return false;
+        }
+        final NonEncodableDiscreteResources other = (NonEncodableDiscreteResources) obj;
+        return Objects.equals(this.values, other.values);
+    }
+
+    @Override
+    public String toString() {
+        return MoreObjects.toStringHelper(this)
+                .add("values", values)
+                .toString();
+    }
+}

@@ -59,7 +59,7 @@ class TransactionalDiscreteResourceSubStore {
             return true;
         }
 
-        DiscreteResources requested = new DiscreteResources(values);
+        DiscreteResources requested = new NonEncodableDiscreteResources(values);
         DiscreteResources oldValues = childMap.putIfAbsent(key, requested);
         if (oldValues == null) {
             return true;