1 package org.apache.commons.jcs.utils.access; 2 3 /* 4 * Licensed to the Apache Software Foundation (ASF) under one 5 * or more contributor license agreements. See the NOTICE file 6 * distributed with this work for additional information 7 * regarding copyright ownership. The ASF licenses this file 8 * to you under the Apache License, Version 2.0 (the 9 * "License"); you may not use this file except in compliance 10 * with the License. You may obtain a copy of the License at 11 * 12 * http://www.apache.org/licenses/LICENSE-2.0 13 * 14 * Unless required by applicable law or agreed to in writing, 15 * software distributed under the License is distributed on an 16 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY 17 * KIND, either express or implied. See the License for the 18 * specific language governing permissions and limitations 19 * under the License. 20 */ 21 22 /** 23 * Interface for doing a piece of work which is expected to be cached. This is 24 * meant to be used in conjunction with JCSWorker. 25 * <p> 26 * Implement doWork() to return the work being done. isFinished() should return 27 * false until setFinished(true) is called, after which time it should return 28 * true. 29 * <p> 30 * @author tsavo 31 */ 32 public interface JCSWorkerHelper<V> 33 { 34 /** 35 * Tells us whether or not the work has been completed. This will be called 36 * automatically by JCSWorker. You should not call it yourself. 37 * <p> 38 * @return True if the work has already been done, otherwise false. 39 */ 40 boolean isFinished(); 41 42 /** 43 * Sets whether or not the work has been done. 44 * <p> 45 * @param isFinished 46 * True if the work has already been done, otherwise false. 47 */ 48 void setFinished( boolean isFinished ); 49 50 /** 51 * The method to implement to do the work that should be cached. JCSWorker 52 * will call this itself! You should not call this directly. 53 * <p> 54 * @return The result of doing the work to be cached. 55 * @throws Exception 56 * If anything goes wrong while doing the work, an Exception 57 * should be thrown. 58 */ 59 V doWork() throws Exception; 60 }