| /* |
| * 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.reef.task; |
| |
| import org.apache.reef.annotations.audience.Public; |
| import org.apache.reef.annotations.audience.TaskSide; |
| |
| /** |
| * The interface for Tasks. |
| * <p> |
| * This interface is to be implemented for Tasks. |
| * <p> |
| * The main entry point for a Task is the call() method inherited from |
| * {@link java.util.concurrent.Callable}. The REEF Evaluator will call this method in order to run |
| * the Task. The byte[] returned by it will be pushed to the Job Driver. |
| */ |
| @TaskSide |
| @Public |
| public interface Task { |
| |
| /** |
| * Called by the resourcemanager harness to execute the task. |
| * |
| * @param memento the memento objected passed down by the driver. |
| * @return the user defined return value |
| * @throws Exception whenever the Task encounters an unsolved issue. |
| * This Exception will be thrown at the Driver's event handler. |
| */ |
| byte[] call(byte[] memento) throws Exception; |
| } |