| 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 org.springframework.batch.item.AbstractItemReader; |
| 20 | import org.springframework.batch.item.ItemReader; |
| 21 | import org.springframework.beans.factory.InitializingBean; |
| 22 | import org.springframework.util.Assert; |
| 23 | |
| 24 | /** |
| 25 | * Simple wrapper around {@link ItemReader}. The input source is expected to |
| 26 | * take care of open and close operations. If necessary it should be registered |
| 27 | * as a step scoped bean to ensure that the lifecycle methods are called. |
| 28 | * |
| 29 | * @author Dave Syer |
| 30 | */ |
| 31 | public class DelegatingItemReader extends AbstractItemReader implements InitializingBean { |
| 32 | |
| 33 | private ItemReader itemReader; |
| 34 | |
| 35 | /** |
| 36 | * Default constructor. |
| 37 | */ |
| 38 | public DelegatingItemReader() { |
| 39 | super(); |
| 40 | } |
| 41 | |
| 42 | /** |
| 43 | * Convenience constructor for setting mandatory property. |
| 44 | */ |
| 45 | public DelegatingItemReader(ItemReader itemReader) { |
| 46 | this(); |
| 47 | this.itemReader = itemReader; |
| 48 | } |
| 49 | |
| 50 | public void afterPropertiesSet() throws Exception { |
| 51 | Assert.notNull(itemReader, "ItemReader must not be null."); |
| 52 | } |
| 53 | |
| 54 | /** |
| 55 | * Get the next object from the input source. |
| 56 | * @throws Exception |
| 57 | * @see org.springframework.batch.item.ItemReader#read() |
| 58 | */ |
| 59 | public Object read() throws Exception { |
| 60 | return itemReader.read(); |
| 61 | } |
| 62 | |
| 63 | /** |
| 64 | * Setter for input source. |
| 65 | * @param source |
| 66 | */ |
| 67 | public void setItemReader(ItemReader source) { |
| 68 | this.itemReader = source; |
| 69 | } |
| 70 | |
| 71 | /* |
| 72 | * (non-Javadoc) |
| 73 | * @see org.springframework.batch.item.ItemStream#mark(org.springframework.batch.item.ExecutionContext) |
| 74 | */ |
| 75 | public void mark() { |
| 76 | itemReader.mark(); |
| 77 | } |
| 78 | |
| 79 | /* |
| 80 | * (non-Javadoc) |
| 81 | * @see org.springframework.batch.item.ItemStream#reset(org.springframework.batch.item.ExecutionContext) |
| 82 | */ |
| 83 | public void reset() { |
| 84 | itemReader.reset(); |
| 85 | } |
| 86 | } |