abstractautowirecapablebeanfactory.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.beans.PropertyDescriptor;
import java.lang.reflect.Constructor;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.lang.reflect.Modifier;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collections;
import java.util.HashMap;
import java.util.HashSet;
import java.util.Iterator;
import java.util.LinkedList;
import java.util.List;
import java.util.Map;
import java.util.Set;
import java.util.TreeSet;

import org.springframework.beans.BeanUtils;
import org.springframework.beans.BeanWrapper;
import org.springframework.beans.BeanWrapperImpl;
import org.springframework.beans.BeansException;
import org.springframework.beans.FatalBeanException;
import org.springframework.beans.MutablePropertyValues;
import org.springframework.beans.PropertyAccessorUtils;
import org.springframework.beans.PropertyValue;
import org.springframework.beans.PropertyValues;
import org.springframework.beans.factory.BeanClassLoaderAware;
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.BeanFactoryAware;
import org.springframework.beans.factory.BeanNameAware;
import org.springframework.beans.factory.FactoryBean;
import org.springframework.beans.factory.InitializingBean;
import org.springframework.beans.factory.UnsatisfiedDependencyException;
import org.springframework.beans.factory.config.AutowireCapableBeanFactory;
import org.springframework.beans.factory.config.BeanDefinition;
import org.springframework.beans.factory.config.BeanPostProcessor;
import org.springframework.beans.factory.config.ConfigurableBeanFactory;
import org.springframework.beans.factory.config.InstantiationAwareBeanPostProcessor;
import org.springframework.beans.factory.config.SmartInstantiationAwareBeanPostProcessor;
import org.springframework.beans.factory.config.TypedStringValue;
import org.springframework.util.ReflectionUtils;
import org.springframework.util.StringUtils;

/**
 * Abstract bean factory superclass that implements default bean creation,
 * with the full capabilities specified by the {@link RootBeanDefinition} class.
 * Implements the {@link org.springframework.beans.factory.config.AutowireCapableBeanFactory}
 * interface in addition to AbstractBeanFactory's {@link #createBean} method.
 *
 * <p>Provides bean creation (with constructor resolution), property population,
 * wiring (including autowiring), and initialization. Handles runtime bean
 * references, resolves managed collections, calls initialization methods, etc.
 * Supports autowiring constructors, properties by name, and properties by type.
 *
 * <p>The main template method to be implemented by subclasses is
 * {@link #findAutowireCandidates}, used for autowiring by type. In case of
 * a factory which is capable of searching its bean definitions, matching
 * beans will typically be implemented through such a search. For other
 * factory styles, simplified matching algorithms can be implemented.
 *
 * <p>Note that this class does <i>not</i> assume or implement bean definition
 * registry capabilities. See {@link DefaultListableBeanFactory} for an implementation
 * of the {@link org.springframework.beans.factory.ListableBeanFactory} and
 * {@link BeanDefinitionRegistry} interfaces, which represent the API and SPI
 * view of such a factory, respectively.
 *
 * @author Rod Johnson
 * @author Juergen Hoeller
 * @author Rob Harrop
 * @since 13.02.2004
 * @see RootBeanDefinition
 * @see DefaultListableBeanFactory
 * @see BeanDefinitionRegistry
 */
public abstract class AbstractAutowireCapableBeanFactory extends AbstractBeanFactory
		implements AutowireCapableBeanFactory {

	private InstantiationStrategy instantiationStrategy = new CglibSubclassingInstantiationStrategy();

	/** Whether to automatically try to resolve circular references between beans */
	private boolean allowCircularReferences = true;

	/**
	 * Whether to resort to injecting a raw bean instance in case of circular reference,
	 * even if the injected bean eventually got wrapped.
	 */
	private boolean allowRawInjectionDespiteWrapping = false;

	/**
	 * Dependency types to ignore on dependency check and autowire, as Set of
	 * Class objects: for example, String. Default is none.
	 */
	private final Set ignoredDependencyTypes = new HashSet();

	/**
	 * Dependency interfaces to ignore on dependency check and autowire, as Set of
	 * Class objects. By default, only the BeanFactory interface is ignored.
	 */
	private final Set ignoredDependencyInterfaces = new HashSet();

	/** Cache of unfinished FactoryBean instances: FactoryBean name --> BeanWrapper */
	private final Map factoryBeanInstanceCache = new HashMap();

	/** Cache of filtered PropertyDescriptors: bean Class -> PropertyDescriptor array */
	private final Map filteredPropertyDescriptorsCache = new HashMap();


	/**
	 * Create a new AbstractAutowireCapableBeanFactory.
	 */
	public AbstractAutowireCapableBeanFactory() {
		super();
		ignoreDependencyInterface(BeanNameAware.class);
		ignoreDependencyInterface(BeanFactoryAware.class);
		ignoreDependencyInterface(BeanClassLoaderAware.class);
	}

	/**
	 * Create a new AbstractAutowireCapableBeanFactory with the given parent.
	 * @param parentBeanFactory parent bean factory, or <code>null</code> if none
	 */
	public AbstractAutowireCapableBeanFactory(BeanFactory parentBeanFactory) {
		this();
		setParentBeanFactory(parentBeanFactory);
	}


	/**
	 * Set the instantiation strategy to use for creating bean instances.
	 * Default is CglibSubclassingInstantiationStrategy.
	 * @see CglibSubclassingInstantiationStrategy
	 */
	public void setInstantiationStrategy(InstantiationStrategy instantiationStrategy) {
		this.instantiationStrategy = instantiationStrategy;
	}

	/**
	 * Return the instantiation strategy to use for creating bean instances.
	 */
	protected InstantiationStrategy getInstantiationStrategy() {
		return this.instantiationStrategy;
	}

	/**
	 * Set whether to allow circular references between beans - and automatically
	 * try to resolve them.
	 * <p>Note that circular reference resolution means that one of the involved beans
	 * will receive a reference to another bean that is not fully initialized yet.
	 * This can lead to subtle and not-so-subtle side effects on initialization;
	 * it does work fine for many scenarios, though.
	 * <p>Default is "true". Turn this off to throw an exception when encountering
	 * a circular reference, disallowing them completely.
	 * <p><b>NOTE:</b> It is generally recommended to not rely on circular references
	 * between your beans. Refactor your application logic to have the two beans
	 * involved delegate to a third bean that encapsulates their common logic.
	 */
	public void setAllowCircularReferences(boolean allowCircularReferences) {
		this.allowCircularReferences = allowCircularReferences;
	}

	/**
	 * Set whether to allow the raw injection of a bean instance into some other
	 * bean's property, despite the injected bean eventually getting wrapped
	 * (for example, through AOP auto-proxying).
	 * <p>This will only be used as a last resort in case of a circular reference
	 * that cannot be resolved otherwise: essentially, preferring a raw instance
	 * getting injected over a failure of the entire bean wiring process.
	 * <p>Default is "false", as of Spring 2.0. Turn this on to allow for non-wrapped
	 * raw beans injected into some of your references, which was Spring 1.2's
	 * (arguably unclean) default behavior.
	 * <p><b>NOTE:</b> It is generally recommended to not rely on circular references
	 * between your beans, in particular with auto-proxying involved.
	 * @see #setAllowCircularReferences
	 */
	public void setAllowRawInjectionDespiteWrapping(boolean allowRawInjectionDespiteWrapping) {
		this.allowRawInjectionDespiteWrapping = allowRawInjectionDespiteWrapping;
	}

	/**
	 * Ignore the given dependency type for autowiring:
	 * for example, String. Default is none.
	 */
	public void ignoreDependencyType(Class type) {
		this.ignoredDependencyTypes.add(type);
	}

	/**
	 * Ignore the given dependency interface for autowiring.
	 * <p>This will typically be used by application contexts to register
	 * dependencies that are resolved in other ways, like BeanFactory through
	 * BeanFactoryAware or ApplicationContext through ApplicationContextAware.
	 * <p>By default, only the BeanFactoryAware interface is ignored.
	 * For further types to ignore, invoke this method for each type.
	 * @see org.springframework.beans.factory.BeanFactoryAware
	 * @see org.springframework.context.ApplicationContextAware
	 */
	public void ignoreDependencyInterface(Class ifc) {
		this.ignoredDependencyInterfaces.add(ifc);
	}


	public void copyConfigurationFrom(ConfigurableBeanFactory otherFactory) {
		super.copyConfigurationFrom(otherFactory);
		if (otherFactory instanceof AbstractAutowireCapableBeanFactory) {
			AbstractAutowireCapableBeanFactory otherAutowireFactory =
					(AbstractAutowireCapableBeanFactory) otherFactory;
			this.instantiationStrategy = otherAutowireFactory.instantiationStrategy;
			this.allowCircularReferences = otherAutowireFactory.allowCircularReferences;
			this.ignoredDependencyTypes.addAll(otherAutowireFactory.ignoredDependencyTypes);
			this.ignoredDependencyInterfaces.addAll(otherAutowireFactory.ignoredDependencyInterfaces);
		}
	}


	//---------------------------------------------------------------------
	// Implementation of AutowireCapableBeanFactory interface
	//---------------------------------------------------------------------

	public Object createBean(Class beanClass, int autowireMode, boolean dependencyCheck)
			throws BeansException {

		// Use non-singleton bean definition, to avoid registering bean as dependent bean.
		RootBeanDefinition bd = new RootBeanDefinition(beanClass, autowireMode, dependencyCheck);
		bd.setScope(BeanDefinition.SCOPE_PROTOTYPE);
		return createBean(beanClass.getName(), bd, null);
	}

	public Object autowire(Class beanClass, int autowireMode, boolean dependencyCheck)
			throws BeansException {

		// Use non-singleton bean definition, to avoid registering bean as dependent bean.
		RootBeanDefinition bd = new RootBeanDefinition(beanClass, autowireMode, dependencyCheck);
		bd.setScope(BeanDefinition.SCOPE_PROTOTYPE);
		if (bd.getResolvedAutowireMode() == AUTOWIRE_CONSTRUCTOR) {
			return autowireConstructor(beanClass.getName(), bd, null).getWrappedInstance();
		}
		else {
			Object bean = getInstantiationStrategy().instantiate(bd, null, this);
			populateBean(beanClass.getName(), bd, new BeanWrapperImpl(bean));
			return bean;
		}
	}

	public void autowireBeanProperties(Object existingBean, int autowireMode, boolean dependencyCheck)
			throws BeansException {

		if (autowireMode != AUTOWIRE_BY_NAME && autowireMode != AUTOWIRE_BY_TYPE) {
			throw new IllegalArgumentException("Just constants AUTOWIRE_BY_NAME and AUTOWIRE_BY_TYPE allowed");
		}
		// Use non-singleton bean definition, to avoid registering bean as dependent bean.
		RootBeanDefinition bd = new RootBeanDefinition(existingBean.getClass(), autowireMode, dependencyCheck);
		bd.setScope(BeanDefinition.SCOPE_PROTOTYPE);
		populateBean(existingBean.getClass().getName(), bd, new BeanWrapperImpl(existingBean));
	}

	public void applyBeanPropertyValues(Object existingBean, String beanName) throws BeansException {
		RootBeanDefinition bd = getMergedBeanDefinition(beanName, true);
		BeanWrapper bw = new BeanWrapperImpl(existingBean);
		initBeanWrapper(bw);
		applyPropertyValues(beanName, bd, bw, bd.getPropertyValues());
	}

	public Object configureBean(Object existingBean, String beanName) throws BeansException {
		RootBeanDefinition bd = getMergedBeanDefinition(beanName, true);
		BeanWrapper bw = new BeanWrapperImpl(existingBean);
		initBeanWrapper(bw);
		populateBean(beanName, bd, bw);
		return initializeBean(beanName, existingBean, bd);
	}

	public Object initializeBean(Object existingBean, String beanName) {
		return initializeBean(beanName, existingBean, null);
	}

	public Object applyBeanPostProcessorsBeforeInitialization(Object existingBean, String beanName)
			throws BeansException {

		Object result = existingBean;
		for (Iterator it = getBeanPostProcessors().iterator(); it.hasNext();) {
			BeanPostProcessor beanProcessor = (BeanPostProcessor) it.next();
			result = beanProcessor.postProcessBeforeInitialization(result, beanName);
		}
		return result;
	}

	public Object applyBeanPostProcessorsAfterInitialization(Object existingBean, String beanName)
			throws BeansException {

		Object result = existingBean;
		for (Iterator it = getBeanPostProcessors().iterator(); it.hasNext();) {
			BeanPostProcessor beanProcessor = (BeanPostProcessor) it.next();
			result = beanProcessor.postProcessAfterInitialization(result, beanName);
		}
		return result;
	}


	//---------------------------------------------------------------------
	// Implementation of relevant AbstractBeanFactory template methods
	//---------------------------------------------------------------------

	/**
	 * Central method of this class: creates a bean instance,
	 * populates the bean instance, applies post-processors, etc.
	 * <p>Differentiates between default bean instantiation, use of a
	 * factory method, and autowiring a constructor.
	 * @see #instantiateBean
	 * @see #instantiateUsingFactoryMethod
	 * @see #autowireConstructor
	 */