| /** |
| * 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.heron.api.topology; |
| |
| import java.io.Serializable; |
| import java.util.Map; |
| |
| /** |
| * Common methods for all possible components in a topology. This interface is used |
| * when defining topologies using the Java API. |
| */ |
| public interface IComponent extends Serializable { |
| |
| /** |
| * Declare the output schema for all the streams of this topology. |
| * |
| * @param declarer this is used to declare output stream ids, output fields, and whether or not each output stream is a direct stream |
| */ |
| void declareOutputFields(OutputFieldsDeclarer declarer); |
| |
| /** |
| * Declare configuration specific to this component. Only a subset of the "topology.*" configs can |
| * be overridden. The component configuration can be further overridden when constructing the |
| * topology using {@link TopologyBuilder} |
| */ |
| Map<String, Object> getComponentConfiguration(); |
| |
| } |