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.file.transform; 018 019import java.util.ArrayList; 020import java.util.Arrays; 021import java.util.List; 022 023import org.springframework.beans.BeanWrapper; 024import org.springframework.beans.BeanWrapperImpl; 025import org.springframework.beans.factory.InitializingBean; 026import org.springframework.util.Assert; 027 028/** 029 * This is a field extractor for a java bean. Given an array of property names, 030 * it will reflectively call getters on the item and return an array of all the 031 * values. 032 * 033 * @author Dan Garrette 034 * @since 2.0 035 */ 036public class BeanWrapperFieldExtractor<T> implements FieldExtractor<T>, InitializingBean { 037 038 private String[] names; 039 040 /** 041 * @param names field names to be extracted by the {@link #extract(Object)} method. 042 */ 043 public void setNames(String[] names) { 044 Assert.notNull(names, "Names must be non-null"); 045 this.names = Arrays.asList(names).toArray(new String[names.length]); 046 } 047 048 /** 049 * @see org.springframework.batch.item.file.transform.FieldExtractor#extract(java.lang.Object) 050 */ 051 @Override 052 public Object[] extract(T item) { 053 List<Object> values = new ArrayList<Object>(); 054 055 BeanWrapper bw = new BeanWrapperImpl(item); 056 for (String propertyName : this.names) { 057 values.add(bw.getPropertyValue(propertyName)); 058 } 059 return values.toArray(); 060 } 061 062 @Override 063 public void afterPropertiesSet() { 064 Assert.notNull(names, "The 'names' property must be set."); 065 } 066}