1 /* 2 * Licensed to the Apache Software Foundation (ASF) under one or more 3 * contributor license agreements. See the NOTICE file distributed with 4 * this work for additional information regarding copyright ownership. 5 * The ASF licenses this file to You under the Apache License, Version 2.0 6 * (the "License"); you may not use this file except in compliance with 7 * the License. You may obtain a copy of the License at 8 * 9 * http://www.apache.org/licenses/LICENSE-2.0 10 * 11 * Unless required by applicable law or agreed to in writing, software 12 * distributed under the License is distributed on an "AS IS" BASIS, 13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 14 * See the License for the specific language governing permissions and 15 * limitations under the License. 16 */ 17 18 package org.apache.commons.pipeline; 19 20 21 /** 22 * This interface represents a data channel into which objects can be fed. 23 * Feeders act as intermediaries between stages in a pipeline and the drivers 24 * for subsequent stages. Each {@link StageDriver} implementation will 25 * ordinarily provide a custom Feeder implementation that integrates receiving 26 * objects with its internal stage processing workflow. 27 */ 28 public interface Feeder { 29 /** 30 * This Feeder implementation provides a standard, no-op sink for objects. 31 * It is useful for situations like the terminus of a pipeline, where 32 * there is nothing to be done with a generated object. 33 */ 34 public static final Feeder VOID = new Feeder() { 35 public void feed(Object obj) { } 36 }; 37 38 /** 39 * Feeds the specified object to an underlying receiver. 40 * @param obj The object being fed to the receiver. 41 */ 42 public void feed(Object obj); 43 }