| /* |
| * Copyright 2016-present Open Networking Foundation |
| * |
| * 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.onlab.util; |
| |
| import java.util.Objects; |
| |
| import static com.google.common.base.Preconditions.checkNotNull; |
| |
| /** |
| * Abstract identifier backed by another value, e.g. string, int. |
| */ |
| public class Identifier<T> { |
| |
| protected final T identifier; // backing identifier value |
| |
| /** |
| * Constructor for serialization. |
| */ |
| protected Identifier() { |
| this.identifier = null; |
| } |
| |
| /** |
| * Constructs an identifier backed by the specified value. |
| * |
| * @param value the backing value |
| */ |
| protected Identifier(T value) { |
| this.identifier = checkNotNull(value, "Identifier cannot be null."); |
| } |
| |
| /** |
| * Returns the backing identifier value. |
| * |
| * @return identifier |
| */ |
| public T id() { |
| return identifier; |
| } |
| |
| /** |
| * Returns the hashcode of the identifier. |
| * |
| * @return hashcode |
| */ |
| @Override |
| public int hashCode() { |
| return identifier.hashCode(); |
| } |
| |
| /** |
| * Compares two device key identifiers for equality. |
| * |
| * @param obj to compare against |
| * @return true if the objects are equal, false otherwise. |
| */ |
| @Override |
| public boolean equals(Object obj) { |
| if (this == obj) { |
| return true; |
| } |
| if (obj instanceof Identifier) { |
| Identifier that = (Identifier) obj; |
| return this.getClass() == that.getClass() && |
| Objects.equals(this.identifier, that.identifier); |
| } |
| return false; |
| } |
| |
| /** |
| * Returns a string representation of a DeviceKeyId. |
| * |
| * @return string |
| */ |
| public String toString() { |
| return identifier.toString(); |
| } |
| |
| } |