defaultlistablebeanfactory.java

spring api 源代码

/*
 * 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.support;

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

import org.springframework.beans.BeansException;
import org.springframework.beans.factory.BeanCreationException;
import org.springframework.beans.factory.BeanCurrentlyInCreationException;
import org.springframework.beans.factory.BeanDefinitionStoreException;
import org.springframework.beans.factory.BeanFactory;
import org.springframework.beans.factory.BeanFactoryUtils;
import org.springframework.beans.factory.CannotLoadBeanClassException;
import org.springframework.beans.factory.FactoryBean;
import org.springframework.beans.factory.NoSuchBeanDefinitionException;
import org.springframework.beans.factory.SmartFactoryBean;
import org.springframework.beans.factory.config.BeanDefinition;
import org.springframework.beans.factory.config.ConfigurableBeanFactory;
import org.springframework.beans.factory.config.ConfigurableListableBeanFactory;
import org.springframework.core.CollectionFactory;
import org.springframework.util.Assert;
import org.springframework.util.ObjectUtils;
import org.springframework.util.StringUtils;

/**
 * Default implementation of the
 * {@link org.springframework.beans.factory.ListableBeanFactory} and
 * {@link BeanDefinitionRegistry} interfaces: a full-fledged bean factory
 * based on bean definition objects.
 *
 * <p>Typical usage is registering all bean definitions first (possibly read
 * from a bean definition file), before accessing beans. Bean definition lookup
 * is therefore an inexpensive operation in a local bean definition table,
 * operating on pre-built bean definition metadata objects.
 *
 * <p>Can be used as a standalone bean factory, or as a superclass for custom
 * bean factories. Note that readers for specific bean definition formats are
 * typically implemented separately rather than as bean factory subclasses:
 * see for example {@link PropertiesBeanDefinitionReader} and
 * {@link org.springframework.beans.factory.xml.XmlBeanDefinitionReader}.
 *
 * <p>For an alternative implementation of the
 * {@link org.springframework.beans.factory.ListableBeanFactory} interface,
 * have a look at {@link StaticListableBeanFactory}, which manages existing
 * bean instances rather than creating new ones based on bean definitions.
 *
 * @author Rod Johnson
 * @author Juergen Hoeller
 * @since 16 April 2001
 * @see StaticListableBeanFactory
 * @see PropertiesBeanDefinitionReader
 * @see org.springframework.beans.factory.xml.XmlBeanDefinitionReader
 */
public class DefaultListableBeanFactory extends AbstractAutowireCapableBeanFactory
    implements ConfigurableListableBeanFactory, BeanDefinitionRegistry {

	/** Whether to allow re-registration of a different definition with the same name */
	private boolean allowBeanDefinitionOverriding = true;

	/** Whether to allow eager class loading even for lazy-init beans */
	private boolean allowEagerClassLoading = true;

	/** Map of bean definition objects, keyed by bean name */
	private final Map beanDefinitionMap = new HashMap();

	/** List of bean definition names, in registration order */
	private final List beanDefinitionNames = new ArrayList();


	/**
	 * Create a new DefaultListableBeanFactory.
	 */
	public DefaultListableBeanFactory() {
		super();
	}

	/**
	 * Create a new DefaultListableBeanFactory with the given parent.
	 * @param parentBeanFactory the parent BeanFactory
	 */
	public DefaultListableBeanFactory(BeanFactory parentBeanFactory) {
		super(parentBeanFactory);
	}


	/**
	 * Set whether it should be allowed to override bean definitions by registering
	 * a different definition with the same name, automatically replacing the former.
	 * If not, an exception will be thrown. Default is "true".
	 */
	public void setAllowBeanDefinitionOverriding(boolean allowBeanDefinitionOverriding) {
		this.allowBeanDefinitionOverriding = allowBeanDefinitionOverriding;
	}

	/**
	 * Set whether the factory is allowed to eagerly load bean classes
	 * even for bean definitions that are marked as "lazy-init".
	 * <p>Default is "true". Turn this flag off to suppress class loading
	 * for lazy-init beans unless such a bean is explicitly requested.
	 * In particular, by-type lookups will then simply ignore bean definitions
	 * without resolved class name, instead of loading the bean classes on
	 * demand just to perform a type check.
	 * @see AbstractBeanDefinition#setLazyInit
	 */
	public void setAllowEagerClassLoading(boolean allowEagerClassLoading) {
		this.allowEagerClassLoading = allowEagerClassLoading;
	}


	public void copyConfigurationFrom(ConfigurableBeanFactory otherFactory) {
		super.copyConfigurationFrom(otherFactory);
		if (otherFactory instanceof DefaultListableBeanFactory) {
			DefaultListableBeanFactory otherListableFactory = (DefaultListableBeanFactory) otherFactory;
			this.allowBeanDefinitionOverriding = otherListableFactory.allowBeanDefinitionOverriding;
			this.allowEagerClassLoading = otherListableFactory.allowEagerClassLoading;
		}
	}


	//---------------------------------------------------------------------
	// Implementation of ListableBeanFactory interface
	//---------------------------------------------------------------------

	public boolean containsBeanDefinition(String beanName) {
		return this.beanDefinitionMap.containsKey(beanName);
	}

	public int getBeanDefinitionCount() {
		return this.beanDefinitionMap.size();
	}

	public String[] getBeanDefinitionNames() {
		return StringUtils.toStringArray(this.beanDefinitionNames);
	}

	public String[] getBeanNamesForType(Class type) {
		return getBeanNamesForType(type, true, true);
	}

	public String[] getBeanNamesForType(Class type, boolean includePrototypes, boolean allowEagerInit) {
		List result = new ArrayList();

		// Check all bean definitions.
		for (Iterator it = this.beanDefinitionNames.iterator(); it.hasNext();) {
			String beanName = (String) it.next();
			// Only consider bean as eligible if the bean name
			// is not defined as alias for some other bean.
			if (!isAlias(beanName)) {
				RootBeanDefinition mbd = getMergedBeanDefinition(beanName, false);
				// Only check bean definition if it is complete.
				if (!mbd.isAbstract() &&
						(allowEagerInit || mbd.hasBeanClass() || !mbd.isLazyInit() || this.allowEagerClassLoading)) {
					// In case of FactoryBean, match object created by FactoryBean.
					try {
						boolean isFactoryBean = isBeanClassMatch(beanName, mbd, FactoryBean.class);
						boolean matchFound =
								(allowEagerInit || !requiresEagerInitForType(beanName, isFactoryBean, mbd.getFactoryBeanName())) &&
								(includePrototypes || isSingleton(beanName)) && isTypeMatch(beanName, type);
						if (!matchFound && isFactoryBean) {
							// In case of FactoryBean, try to match FactoryBean instance itself next.
							beanName = FACTORY_BEAN_PREFIX + beanName;
							matchFound = (includePrototypes || mbd.isSingleton()) && isTypeMatch(beanName, type);
						}
						if (matchFound) {
							result.add(beanName);
						}
					}
					catch (CannotLoadBeanClassException ex) {
						// Probably contains a placeholder: let's ignore it for type matching purposes.
						if (logger.isDebugEnabled()) {
							logger.debug("Ignoring bean class loading failure for bean '" + beanName + "'", ex);
						}
					}
				}
			}
		}

		// Check singletons too, to catch manually registered singletons.
		String[] singletonNames = getSingletonNames();
		for (int i = 0; i < singletonNames.length; i++) {