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.support;
18
19 import java.util.ArrayList;
20 import java.util.List;
21
22 import org.springframework.aop.support.AopUtils;
23 import org.springframework.batch.item.ItemReader;
24
25 /**
26 * An {@link ItemReader} that pulls data from a list. Useful for testing.
27 *
28 * @author Dave Syer
29 *
30 */
31 public class ListItemReader<T> implements ItemReader<T> {
32
33 private List<T> list;
34
35 public ListItemReader(List<T> list) {
36 // If it is a proxy we assume it knows how to deal with its own state.
37 // (It's probably transaction aware.)
38 if (AopUtils.isAopProxy(list)) {
39 this.list = list;
40 }
41 else {
42 this.list = new ArrayList<T>(list);
43 }
44 }
45
46 @Override
47 public T read() {
48 if (!list.isEmpty()) {
49 return list.remove(0);
50 }
51 return null;
52 }
53
54 }