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.sample.support; 018 019import org.springframework.batch.core.UnexpectedJobExecutionException; 020import org.springframework.batch.item.ItemReader; 021 022/** 023 * Hacked {@link ItemReader} that throws exception on a given record number 024 * (useful for testing restart). 025 * 026 * @author Robert Kasanicky 027 * @author Lucas Ward 028 * 029 */ 030public class ExceptionThrowingItemReaderProxy<T> implements ItemReader<T> { 031 032 private int counter = 0; 033 034 private int throwExceptionOnRecordNumber = 4; 035 036 private ItemReader<T> delegate; 037 038 /** 039 * @param throwExceptionOnRecordNumber The number of record on which 040 * exception should be thrown 041 */ 042 public void setThrowExceptionOnRecordNumber(int throwExceptionOnRecordNumber) { 043 this.throwExceptionOnRecordNumber = throwExceptionOnRecordNumber; 044 } 045 046 @Override 047 public T read() throws Exception { 048 049 counter++; 050 if (counter == throwExceptionOnRecordNumber) { 051 throw new UnexpectedJobExecutionException("Planned failure on count=" + counter); 052 } 053 054 return delegate.read(); 055 } 056 057 public void setDelegate(ItemReader<T> delegate) { 058 this.delegate = delegate; 059 } 060 061}