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 package org.springframework.batch.core;
17
18 import org.springframework.batch.item.ItemProcessor;
19
20 /**
21 * Listener interface for the processing of an item. Implementations
22 * of this interface will be notified before and after an item is
23 * passed to the {@link ItemProcessor} and in the event of any
24 * exceptions thrown by the processor.
25 *
26 * @author Dave Syer
27 *
28 */
29 public interface ItemProcessListener<T, S> extends StepListener {
30
31 /**
32 * Called before {@link ItemProcessor#process(Object)}.
33 *
34 * @param item to be processed.
35 */
36 void beforeProcess(T item);
37
38 /**
39 * Called after {@link ItemProcessor#process(Object)} returns. If the
40 * processor returns null, this method will still be called, with
41 * a null result, allowing for notification of 'filtered' items.
42 *
43 * @param item to be processed
44 * @param result of processing
45 */
46 void afterProcess(T item, S result);
47
48 /**
49 * Called if an exception was thrown from {@link ItemProcessor#process(Object)}.
50 *
51 * @param item attempted to be processed
52 * @param e - exception thrown during processing.
53 */
54 void onProcessError(T item, Exception e);
55 }