| /* |
| * 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.beam.runners.dataflow.worker.util.common.worker; |
| |
| import java.util.List; |
| import javax.annotation.Nullable; |
| import org.apache.beam.runners.dataflow.worker.counters.CounterSet; |
| import org.apache.beam.vendor.guava.v26_0_jre.com.google.common.collect.Lists; |
| |
| /** Abstract executor for WorkItem tasks. */ |
| public interface WorkExecutor extends AutoCloseable { |
| |
| /** Returns the set of output counters for this task. */ |
| CounterSet getOutputCounters(); |
| |
| /** Executes the task. */ |
| public abstract void execute() throws Exception; |
| |
| /** |
| * Returns the worker's current progress. |
| * |
| * <p>May be called at any time, but generally called concurrently to execute(). |
| */ |
| default NativeReader.Progress getWorkerProgress() throws Exception { |
| // By default, return null indicating worker progress not available. |
| return null; |
| } |
| |
| /** See {@link NativeReader.NativeReaderIterator#requestCheckpoint}. */ |
| @Nullable |
| default NativeReader.DynamicSplitResult requestCheckpoint() throws Exception { |
| // By default, checkpointing does nothing. |
| return null; |
| } |
| |
| /** |
| * See {@link NativeReader.NativeReaderIterator#requestDynamicSplit}. Makes sense only for tasks |
| * that read input. |
| */ |
| @Nullable |
| default NativeReader.DynamicSplitResult requestDynamicSplit( |
| NativeReader.DynamicSplitRequest splitRequest) throws Exception { |
| // By default, dynamic splitting is unsupported. |
| return null; |
| } |
| |
| @Override |
| default void close() throws Exception { |
| // By default, nothing to close or shut down. |
| } |
| |
| /** |
| * Requests that the executor abort as soon as possible. |
| * |
| * <p>Thread-safe. May be called at any time after execute() begins. |
| */ |
| default void abort() { |
| // By default, does nothing. Expensive operations should override this. |
| } |
| |
| /** |
| * Reports the sink index of any WriteOperation that did not produce output. NOTE this is only |
| * used for FlumeWriteOperaton for now. |
| */ |
| default List<Integer> reportProducedEmptyOutput() { |
| return Lists.newArrayList(); |
| } |
| } |