org.apache.crunch.Emitter Maven / Gradle / Ivy
/**
* 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.crunch;
/**
* Interface for writing outputs from a {@link DoFn}.
*
*/
public interface Emitter {
/**
* Write the emitted value to the next stage of the pipeline.
*
* @param emitted
* The value to write
*/
void emit(T emitted);
/**
* Flushes any values cached by this emitter. Called during the cleanup stage.
*/
void flush();
}