| /* |
| * * |
| * * 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.tez.runtime.api; |
| |
| import java.util.List; |
| |
| import org.apache.hadoop.classification.InterfaceAudience.Public; |
| |
| |
| /** |
| * Represents an input through which a TezProcessor receives data on an edge. |
| * <p/> |
| * |
| * This interface has methods which are used by the Tez framework to control the Input. |
| * <p/> |
| * |
| * During initialization, Inputs must specify an initial memory requirement via |
| * {@link InputContext}.requestInitialMemory |
| * <p/> |
| * |
| * |
| * Inputs must also inform the framework once they are ready to be consumed. |
| * This typically means that the Processor will not block when reading from the |
| * corresponding Input. This is done via {@link InputContext}.inputIsReady. |
| * Inputs choose the policy on when they are ready. |
| * |
| * Input implementations are expected to derive from {@link AbstractLogicalInput} |
| */ |
| @Public |
| public interface InputFrameworkInterface { |
| /** |
| * Initializes the <code>Input</code>. |
| * |
| * @return list of events that were generated during initialization |
| * @throws Exception |
| * if an error occurs |
| */ |
| public List<Event> initialize() throws Exception; |
| |
| /** |
| * Handles user and system generated {@link Event}s, which typically carry |
| * information such as an output being available on the previous vertex. |
| * |
| * @param inputEvents |
| * the list of {@link Event}s |
| */ |
| public void handleEvents(List<Event> inputEvents) throws Exception; |
| |
| |
| |
| /** |
| * Closes the <code>Input</code> |
| * |
| * @return list of events that were generated during close |
| * @throws Exception |
| * if an error occurs |
| */ |
| public List<Event> close() throws Exception; |
| } |