001/* 002 * Copyright 2006-2007 the original author or authors. 003 * 004 * Licensed under the Apache License, Version 2.0 (the "License"); 005 * you may not use this file except in compliance with the License. 006 * You may obtain a copy of the License at 007 * 008 * https://www.apache.org/licenses/LICENSE-2.0 009 * 010 * Unless required by applicable law or agreed to in writing, software 011 * distributed under the License is distributed on an "AS IS" BASIS, 012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 013 * See the License for the specific language governing permissions and 014 * limitations under the License. 015 */ 016 017package org.springframework.batch.item.support; 018 019import java.util.ArrayList; 020import java.util.List; 021 022import org.springframework.aop.support.AopUtils; 023import org.springframework.batch.item.ItemReader; 024 025/** 026 * An {@link ItemReader} that pulls data from a list. Useful for testing. 027 * 028 * @author Dave Syer 029 * 030 */ 031public class ListItemReader<T> implements ItemReader<T> { 032 033 private List<T> list; 034 035 public ListItemReader(List<T> list) { 036 // If it is a proxy we assume it knows how to deal with its own state. 037 // (It's probably transaction aware.) 038 if (AopUtils.isAopProxy(list)) { 039 this.list = list; 040 } 041 else { 042 this.list = new ArrayList<T>(list); 043 } 044 } 045 046 @Override 047 public T read() { 048 if (!list.isEmpty()) { 049 return list.remove(0); 050 } 051 return null; 052 } 053 054}