| /* |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you 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.apache.nemo.runtime.common.metric; |
| |
| import java.io.Serializable; |
| import java.util.List; |
| |
| /** |
| * Interface for metric which contians its state. |
| * |
| * @param <T> class of state of the metric. |
| */ |
| public interface StateMetric<T extends Serializable> extends Metric { |
| /** |
| * Get its list of {@link StateTransitionEvent}. |
| * |
| * @return list of events. |
| */ |
| List<StateTransitionEvent<T>> getStateTransitionEvents(); |
| |
| /** |
| * Add a {@link StateTransitionEvent} to the metric. |
| * |
| * @param prevState previous state. |
| * @param newState new state. |
| */ |
| void addEvent(final T prevState, final T newState); |
| } |