| /* |
| * 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.ImmutableSet; |
| import org.onosproject.net.resource.DiscreteResource; |
| import org.onosproject.net.resource.DiscreteResourceId; |
| |
| import java.util.Optional; |
| import java.util.Set; |
| |
| /** |
| * Represents an empty set of discrete resource. |
| */ |
| final class EmptyDiscreteResources implements DiscreteResources { |
| static final EmptyDiscreteResources INSTANCE = new EmptyDiscreteResources(); |
| |
| // for serializer |
| private EmptyDiscreteResources() {} |
| |
| @Override |
| public Optional<DiscreteResource> lookup(DiscreteResourceId id) { |
| return Optional.empty(); |
| } |
| |
| @Override |
| public DiscreteResources difference(DiscreteResources other) { |
| return this; |
| } |
| |
| @Override |
| public boolean isEmpty() { |
| return true; |
| } |
| |
| @Override |
| public boolean containsAny(Set<DiscreteResource> other) { |
| return false; |
| } |
| |
| @Override |
| public DiscreteResources add(DiscreteResources other) { |
| return other; |
| } |
| |
| @Override |
| public Set<DiscreteResource> values() { |
| return ImmutableSet.of(); |
| } |
| |
| @Override |
| public int hashCode() { |
| return INSTANCE.hashCode(); |
| } |
| |
| @Override |
| public boolean equals(Object object) { |
| return object instanceof DiscreteResources && ((DiscreteResources) object).isEmpty(); |
| } |
| |
| @Override |
| public String toString() { |
| return MoreObjects.toStringHelper(this) |
| .add("values", ImmutableSet.of()) |
| .toString(); |
| } |
| |
| @Override |
| public <T> Set<DiscreteResource> valuesOf(Class<T> cls) { |
| return ImmutableSet.of(); |
| } |
| } |