1 /*
2 * Copyright 2006-2007 the original author or authors.
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17 package org.springframework.batch.item;
18
19 /**
20 * <p>
21 * Marker interface defining a contract for periodically storing state and restoring from that state should an error
22 * occur.
23 * <p>
24 *
25 * @author Dave Syer
26 * @author Lucas Ward
27 *
28 */
29 public interface ItemStream {
30
31 /**
32 * Open the stream for the provided {@link ExecutionContext}.
33 *
34 * @throws IllegalArgumentException if context is null
35 */
36 void open(ExecutionContext executionContext) throws ItemStreamException;
37
38 /**
39 * Indicates that the execution context provided during open is about to be saved. If any state is remaining, but
40 * has not been put in the context, it should be added here.
41 *
42 * @param executionContext to be updated
43 * @throws IllegalArgumentException if executionContext is null.
44 */
45 void update(ExecutionContext executionContext) throws ItemStreamException;
46
47 /**
48 * If any resources are needed for the stream to operate they need to be destroyed here. Once this method has been
49 * called all other methods (except open) may throw an exception.
50 */
51 void close() throws ItemStreamException;
52 }