| 1 | /* |
| 2 | * Copyright 2012 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.data; |
| 18 | |
| 19 | import java.util.List; |
| 20 | |
| 21 | import org.apache.commons.logging.Log; |
| 22 | import org.apache.commons.logging.LogFactory; |
| 23 | import org.springframework.batch.item.ItemWriter; |
| 24 | import org.springframework.beans.factory.InitializingBean; |
| 25 | import org.springframework.data.neo4j.template.Neo4jOperations; |
| 26 | import org.springframework.util.Assert; |
| 27 | import org.springframework.util.CollectionUtils; |
| 28 | |
| 29 | /** |
| 30 | * <p> |
| 31 | * A {@link ItemWriter} implementation that writes to a Neo4j database using an |
| 32 | * implementation of Spring Data's {@link Neo4jOperations}. |
| 33 | * </p> |
| 34 | * |
| 35 | * <p> |
| 36 | * This writer is thread safe once all properties are set (normal singleton |
| 37 | * behavior) so it can be used in multiple concurrent transactions. |
| 38 | * </p> |
| 39 | * |
| 40 | * @author Michael Minella |
| 41 | * |
| 42 | */ |
| 43 | public class Neo4jItemWriter<T> implements ItemWriter<T>, InitializingBean { |
| 44 | |
| 45 | protected static final Log logger = LogFactory |
| 46 | .getLog(Neo4jItemWriter.class); |
| 47 | |
| 48 | private boolean delete = false; |
| 49 | |
| 50 | private Neo4jOperations template; |
| 51 | |
| 52 | public void setDelete(boolean delete) { |
| 53 | this.delete = delete; |
| 54 | } |
| 55 | |
| 56 | /** |
| 57 | * Set the {@link Neo4jOperations} to be used to save items |
| 58 | * |
| 59 | * @param template the template implementation to be used |
| 60 | */ |
| 61 | public void setTemplate(Neo4jOperations template) { |
| 62 | this.template = template; |
| 63 | } |
| 64 | |
| 65 | /** |
| 66 | * Checks mandatory properties |
| 67 | * |
| 68 | * @see InitializingBean#afterPropertiesSet() |
| 69 | */ |
| 70 | public void afterPropertiesSet() throws Exception { |
| 71 | Assert.state(template != null, "A Neo4JOperations implementation is required"); |
| 72 | } |
| 73 | |
| 74 | /** |
| 75 | * Write all items to the data store. |
| 76 | * |
| 77 | * @see org.springframework.batch.item.ItemWriter#write(java.util.List) |
| 78 | */ |
| 79 | public void write(List<? extends T> items) throws Exception { |
| 80 | if(!CollectionUtils.isEmpty(items)) { |
| 81 | doWrite(items); |
| 82 | } |
| 83 | } |
| 84 | |
| 85 | /** |
| 86 | * Performs the actual write using the template. This can be overriden by |
| 87 | * a subclass if necessary. |
| 88 | * |
| 89 | * @param items the list of items to be persisted. |
| 90 | */ |
| 91 | protected void doWrite(List<? extends T> items) { |
| 92 | if(delete) { |
| 93 | for (T t : items) { |
| 94 | template.delete(t); |
| 95 | } |
| 96 | } |
| 97 | else { |
| 98 | for (T t : items) { |
| 99 | template.save(t); |
| 100 | } |
| 101 | } |
| 102 | } |
| 103 | } |