Spring Framework example source code file (ListFactoryBean.java)

This example Spring Framework source code file (ListFactoryBean.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Java - Spring Framework tags/keywords

abstractfactorybean, class, class, illegalargumentexception, illegalargumentexception, iterator, list, list, listfactorybean, listfactorybean, object, typeconverter, util

The Spring Framework ListFactoryBean.java source code

/*
 * Copyright 2002-2007 the original author or authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.springframework.beans.factory.config;

import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;

import org.springframework.beans.BeanUtils;
import org.springframework.beans.TypeConverter;
import org.springframework.core.GenericCollectionTypeResolver;
import org.springframework.core.JdkVersion;

/**
 * Simple factory for shared List instances. Allows for central setup
 * of Lists via the "list" element in XML bean definitions.
 *
 * @author Juergen Hoeller
 * @since 09.12.2003
 * @see SetFactoryBean
 * @see MapFactoryBean
 */
public class ListFactoryBean extends AbstractFactoryBean {

	private List sourceList;

	private Class targetListClass;


	/**
	 * Set the source List, typically populated via XML "list" elements.
	 */
	public void setSourceList(List sourceList) {
		this.sourceList = sourceList;
	}

	/**
	 * Set the class to use for the target List. Can be populated with a fully
	 * qualified class name when defined in a Spring application context.
	 * <p>Default is a java.util.ArrayList.
	 * @see java.util.ArrayList
	 */
	public void setTargetListClass(Class targetListClass) {
		if (targetListClass == null) {
			throw new IllegalArgumentException("'targetListClass' must not be null");
		}
		if (!List.class.isAssignableFrom(targetListClass)) {
			throw new IllegalArgumentException("'targetListClass' must implement [java.util.List]");
		}
		this.targetListClass = targetListClass;
	}


	public Class getObjectType() {
		return List.class;
	}

	protected Object createInstance() {
		if (this.sourceList == null) {
			throw new IllegalArgumentException("'sourceList' is required");
		}
		List result = null;
		if (this.targetListClass != null) {
			result = (List) BeanUtils.instantiateClass(this.targetListClass);
		}
		else {
			result = new ArrayList(this.sourceList.size());
		}
		Class valueType = null;
		if (this.targetListClass != null && JdkVersion.isAtLeastJava15()) {
			valueType = GenericCollectionTypeResolver.getCollectionType(this.targetListClass);
		}
		if (valueType != null) {
			TypeConverter converter = getBeanTypeConverter();
			for (Iterator it = this.sourceList.iterator(); it.hasNext();) {
				result.add(converter.convertIfNecessary(it.next(), valueType));
			}
		}
		else {
			result.addAll(this.sourceList);
		}
		return result;
	}

}