com.twitter.heron.api.topology.IComponent Maven / Gradle / Ivy
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// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
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//
// http://www.apache.org/licenses/LICENSE-2.0
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// 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
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/**
* 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 com.twitter.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 getComponentConfiguration();
}