| /* |
| * 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.ignite.internal.pagememory.util; |
| |
| import java.util.concurrent.CancellationException; |
| import java.util.concurrent.CompletableFuture; |
| import java.util.concurrent.ExecutorService; |
| import org.apache.ignite.internal.close.ManuallyCloseable; |
| import org.apache.ignite.internal.future.InFlightFutures; |
| |
| /** |
| * Executor for {@link GradualTask}s. See GradualTask documentation for details. |
| * |
| * <p>This executor owns an executor service that it is passed, so it shuts it down when being closed. |
| * |
| * @see GradualTask |
| */ |
| public class GradualTaskExecutor implements ManuallyCloseable { |
| private final ExecutorService executor; |
| |
| private final InFlightFutures inFlightFutures = new InFlightFutures(); |
| |
| private volatile boolean cancelled = false; |
| |
| public GradualTaskExecutor(ExecutorService executor) { |
| this.executor = executor; |
| } |
| |
| /** |
| * Starts execution of a {@link GradualTask} and returns a future that completes when the task completes. |
| * |
| * @param task Task to execute. |
| * @return Future that completes when the task completes. |
| */ |
| public CompletableFuture<Void> execute(GradualTask task) { |
| CompletableFuture<Void> future = new CompletableFuture<>(); |
| |
| inFlightFutures.registerFuture(future); |
| |
| Runnable runnable = new Runnable() { |
| @Override |
| public void run() { |
| try { |
| if (cancelled) { |
| future.completeExceptionally(new CancellationException("The executor has been closed")); |
| |
| return; |
| } |
| |
| if (task.isCompleted()) { |
| future.complete(null); |
| |
| return; |
| } |
| |
| runStep(task); |
| |
| if (task.isCompleted()) { |
| future.complete(null); |
| } else if (cancelled) { |
| future.completeExceptionally(new CancellationException("The executor has been closed")); |
| } else { |
| executor.execute(this); |
| } |
| } catch (Error e) { |
| future.completeExceptionally(e); |
| |
| throw e; |
| } catch (Exception e) { |
| future.completeExceptionally(e); |
| } |
| } |
| }; |
| |
| executor.execute(runnable); |
| |
| return future.whenComplete((res, ex) -> task.cleanup()); |
| } |
| |
| /** |
| * Runs a single step from the given {@code task}. |
| */ |
| protected void runStep(GradualTask task) throws Exception { |
| task.runStep(); |
| } |
| |
| @Override |
| public void close() { |
| cancelled = true; |
| |
| inFlightFutures.cancelInFlightFutures(); |
| } |
| |
| /** |
| * Returns the internal thread pool that is actually used to execute tasks. |
| */ |
| public ExecutorService executorService() { |
| return executor; |
| } |
| } |