| /** |
| * 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 |
| * <p> |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * <p> |
| * 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.hadoop.ozone.container.common.volume; |
| |
| import com.google.common.util.concurrent.ListenableFuture; |
| import org.apache.hadoop.classification.InterfaceAudience; |
| import org.apache.hadoop.classification.InterfaceStability; |
| import org.apache.hadoop.hdfs.server.datanode.checker.Checkable; |
| |
| import java.util.Optional; |
| import java.util.concurrent.ExecutorService; |
| import java.util.concurrent.TimeUnit; |
| |
| /** |
| * A class that can be used to schedule an asynchronous check on a given |
| * {@link Checkable}. If the check is successfully scheduled then a |
| * {@link ListenableFuture} is returned. |
| * |
| */ |
| @InterfaceAudience.Private |
| @InterfaceStability.Unstable |
| public interface AsyncChecker<K, V> { |
| |
| /** |
| * Schedule an asynchronous check for the given object. |
| * |
| * @param target object to be checked. |
| * |
| * @param context the interpretation of the context depends on the |
| * target. |
| * |
| * @return returns a {@link Optional of ListenableFuture} that can be used to |
| * retrieve the result of the asynchronous check. |
| */ |
| Optional<ListenableFuture<V>> schedule(Checkable<K, V> target, K context); |
| |
| /** |
| * Cancel all executing checks and wait for them to complete. |
| * First attempts a graceful cancellation, then cancels forcefully. |
| * Waits for the supplied timeout after both attempts. |
| * |
| * See {@link ExecutorService#awaitTermination} for a description of |
| * the parameters. |
| * |
| * @throws InterruptedException |
| */ |
| void shutdownAndWait(long timeout, TimeUnit timeUnit) |
| throws InterruptedException; |
| } |