beandefinitionparserdelegate.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.xml;

import java.util.ArrayList;
import java.util.Arrays;
import java.util.HashSet;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.Properties;
import java.util.Set;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.w3c.dom.Element;
import org.w3c.dom.NamedNodeMap;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;

import org.springframework.beans.PropertyValue;
import org.springframework.beans.factory.BeanDefinitionStoreException;
import org.springframework.beans.factory.config.BeanDefinition;
import org.springframework.beans.factory.config.BeanDefinitionHolder;
import org.springframework.beans.factory.config.ConstructorArgumentValues;
import org.springframework.beans.factory.config.RuntimeBeanNameReference;
import org.springframework.beans.factory.config.RuntimeBeanReference;
import org.springframework.beans.factory.config.TypedStringValue;
import org.springframework.beans.factory.parsing.BeanEntry;
import org.springframework.beans.factory.parsing.ConstructorArgumentEntry;
import org.springframework.beans.factory.parsing.ParseState;
import org.springframework.beans.factory.parsing.PropertyEntry;
import org.springframework.beans.factory.support.AbstractBeanDefinition;
import org.springframework.beans.factory.support.BeanDefinitionReaderUtils;
import org.springframework.beans.factory.support.LookupOverride;
import org.springframework.beans.factory.support.ManagedList;
import org.springframework.beans.factory.support.ManagedMap;
import org.springframework.beans.factory.support.ManagedProperties;
import org.springframework.beans.factory.support.ManagedSet;
import org.springframework.beans.factory.support.MethodOverrides;
import org.springframework.beans.factory.support.ReplaceOverride;
import org.springframework.core.AttributeAccessor;
import org.springframework.util.Assert;
import org.springframework.util.ClassUtils;
import org.springframework.util.CollectionUtils;
import org.springframework.util.ObjectUtils;
import org.springframework.util.StringUtils;
import org.springframework.util.xml.DomUtils;

/**
 * Stateful delegate class used to parse XML bean definitions.
 * Intended for use by both the main parser and any extension
 * {@link BeanDefinitionParser BeanDefinitionParsers}
 * or {@link BeanDefinitionDecorator BeanDefinitionDecorators}.
 *
 * @author Rob Harrop
 * @author Juergen Hoeller
 * @author Rod Johnson
 * @since 2.0
 * @see ParserContext
 * @see DefaultBeanDefinitionDocumentReader
 */
public class BeanDefinitionParserDelegate {

	public static final String BEANS_NAMESPACE_URI = "http://www.springframework.org/schema/beans";

	public static final String BEAN_NAME_DELIMITERS = ",; ";

	/**
	 * Value of a T/F attribute that represents true.
	 * Anything else represents false. Case seNsItive.
	 */
	public static final String TRUE_VALUE = "true";

	public static final String DEFAULT_VALUE = "default";

	public static final String DESCRIPTION_ELEMENT = "description";

	public static final String AUTOWIRE_BY_NAME_VALUE = "byName";

	public static final String AUTOWIRE_BY_TYPE_VALUE = "byType";

	public static final String AUTOWIRE_CONSTRUCTOR_VALUE = "constructor";

	public static final String AUTOWIRE_AUTODETECT_VALUE = "autodetect";

	public static final String DEPENDENCY_CHECK_ALL_ATTRIBUTE_VALUE = "all";

	public static final String DEPENDENCY_CHECK_SIMPLE_ATTRIBUTE_VALUE = "simple";

	public static final String DEPENDENCY_CHECK_OBJECTS_ATTRIBUTE_VALUE = "objects";

	public static final String NAME_ATTRIBUTE = "name";

	public static final String BEAN_ELEMENT = "bean";

	public static final String META_ELEMENT = "meta";

	public static final String ID_ATTRIBUTE = "id";

	public static final String PARENT_ATTRIBUTE = "parent";

	public static final String CLASS_ATTRIBUTE = "class";

	public static final String ABSTRACT_ATTRIBUTE = "abstract";

	public static final String SCOPE_ATTRIBUTE = "scope";

	public static final String SINGLETON_ATTRIBUTE = "singleton";

	public static final String LAZY_INIT_ATTRIBUTE = "lazy-init";

	public static final String AUTOWIRE_ATTRIBUTE = "autowire";

	public static final String AUTOWIRE_CANDIDATE_ATTRIBUTE = "autowire-candidate";

	public static final String DEPENDENCY_CHECK_ATTRIBUTE = "dependency-check";

	public static final String DEPENDS_ON_ATTRIBUTE = "depends-on";

	public static final String INIT_METHOD_ATTRIBUTE = "init-method";

	public static final String DESTROY_METHOD_ATTRIBUTE = "destroy-method";

	public static final String FACTORY_METHOD_ATTRIBUTE = "factory-method";

	public static final String FACTORY_BEAN_ATTRIBUTE = "factory-bean";

	public static final String CONSTRUCTOR_ARG_ELEMENT = "constructor-arg";

	public static final String INDEX_ATTRIBUTE = "index";

	public static final String TYPE_ATTRIBUTE = "type";

	public static final String VALUE_TYPE_ATTRIBUTE = "value-type";

	public static final String KEY_TYPE_ATTRIBUTE = "key-type";

	public static final String PROPERTY_ELEMENT = "property";

	public static final String REF_ATTRIBUTE = "ref";

	public static final String VALUE_ATTRIBUTE = "value";

	public static final String LOOKUP_METHOD_ELEMENT = "lookup-method";

	public static final String REPLACED_METHOD_ELEMENT = "replaced-method";

	public static final String REPLACER_ATTRIBUTE = "replacer";

	public static final String ARG_TYPE_ELEMENT = "arg-type";

	public static final String ARG_TYPE_MATCH_ATTRIBUTE = "match";

	public static final String REF_ELEMENT = "ref";

	public static final String IDREF_ELEMENT = "idref";

	public static final String BEAN_REF_ATTRIBUTE = "bean";

	public static final String LOCAL_REF_ATTRIBUTE = "local";

	public static final String PARENT_REF_ATTRIBUTE = "parent";

	public static final String VALUE_ELEMENT = "value";

	public static final String NULL_ELEMENT = "null";

	public static final String LIST_ELEMENT = "list";

	public static final String SET_ELEMENT = "set";

	public static final String MAP_ELEMENT = "map";

	public static final String ENTRY_ELEMENT = "entry";

	public static final String KEY_ELEMENT = "key";

	public static final String KEY_ATTRIBUTE = "key";

	public static final String KEY_REF_ATTRIBUTE = "key-ref";

	public static final String VALUE_REF_ATTRIBUTE = "value-ref";

	public static final String PROPS_ELEMENT = "props";

	public static final String PROP_ELEMENT = "prop";

	public static final String MERGE_ATTRIBUTE = "merge";

	public static final String DEFAULT_LAZY_INIT_ATTRIBUTE = "default-lazy-init";

	public static final String DEFAULT_AUTOWIRE_ATTRIBUTE = "default-autowire";

	public static final String DEFAULT_DEPENDENCY_CHECK_ATTRIBUTE = "default-dependency-check";

	public static final String DEFAULT_INIT_METHOD_ATTRIBUTE = "default-init-method";

	public static final String DEFAULT_DESTROY_METHOD_ATTRIBUTE = "default-destroy-method";

	public static final String DEFAULT_MERGE_ATTRIBUTE = "default-merge";


	protected final Log logger = LogFactory.getLog(getClass());

	private final XmlReaderContext readerContext;

	private DocumentDefaultsDefinition defaults;

	private ParseState parseState = new ParseState();

	/**
	 * Stores all used bean names so we can enforce uniqueness on a per file basis.
	 */
	private final Set usedNames = new HashSet();


	/**
	 * Create a new BeanDefinitionParserDelegate associated with the
	 * supplied {@link XmlReaderContext}.
	 */
	public BeanDefinitionParserDelegate(XmlReaderContext readerContext) {
		Assert.notNull(readerContext, "XmlReaderContext must not be null");
		this.readerContext = readerContext;
	}

	/**
	 * Get the {@link XmlReaderContext} associated with this helper instance.
	 */
	public final XmlReaderContext getReaderContext() {
		return this.readerContext;
	}


	/**
	 * Invoke the {@link org.springframework.beans.factory.parsing.SourceExtractor} to pull the
	 * source metadata from the supplied {@link Element}.
	 */
	protected Object extractSource(Element ele) {
		return this.readerContext.extractSource(ele);
	}

	/**
	 * Report an error with the given message for the given source element.
	 */
	protected void error(String message, Element source) {
		this.readerContext.error(message, source, this.parseState.snapshot());
	}

	/**
	 * Report an error with the given message for the given source element.
	 */
	protected void error(String message, Element source, Throwable cause) {
		this.readerContext.error(message, source, this.parseState.snapshot(), cause);
	}


	/**
	 * Initialize the default lazy-init, autowire, dependency check settings,
	 * init-method, destroy-method and merge settings.
	 * @see #getDefaults()
	 */
	public void initDefaults(Element root) {
		DocumentDefaultsDefinition defaults = new DocumentDefaultsDefinition();
		defaults.setLazyInit(root.getAttribute(DEFAULT_LAZY_INIT_ATTRIBUTE));
		defaults.setAutowire(root.getAttribute(DEFAULT_AUTOWIRE_ATTRIBUTE));
		defaults.setDependencyCheck(root.getAttribute(DEFAULT_DEPENDENCY_CHECK_ATTRIBUTE));
		if (root.hasAttribute(DEFAULT_INIT_METHOD_ATTRIBUTE)) {
			defaults.setInitMethod(root.getAttribute(DEFAULT_INIT_METHOD_ATTRIBUTE));
		}
		if (root.hasAttribute(DEFAULT_DESTROY_METHOD_ATTRIBUTE)) {
			defaults.setDestroyMethod(root.getAttribute(DEFAULT_DESTROY_METHOD_ATTRIBUTE));
		}
		defaults.setMerge(root.getAttribute(DEFAULT_MERGE_ATTRIBUTE));
		defaults.setSource(this.readerContext.extractSource(root));

		this.defaults = defaults;
		this.readerContext.fireDefaultsRegistered(defaults);
	}

	/**
	 * Return the defaults definition object, or <code>null</code> if the
	 * defaults have been initialized yet.
	 */
	public DocumentDefaultsDefinition getDefaults() {
		return this.defaults;
	}


	/**
	 * Parses the supplied <code>&lt;bean&gt;</code> element. May return <code>null</code>
	 * if there were errors during parse. Errors are reported to the
	 * {@link org.springframework.beans.factory.parsing.ProblemReporter}.
	 */
	public BeanDefinitionHolder parseBeanDefinitionElement(Element ele) {
		return parseBeanDefinitionElement(ele, null);
	}

	/**
	 * Parses the supplied <code>&lt;bean&gt;</code> element. May return <code>null</code>
	 * if there were errors during parse. Errors are reported to the
	 * {@link org.springframework.beans.factory.parsing.ProblemReporter}.
	 */
	public BeanDefinitionHolder parseBeanDefinitionElement(Element ele, BeanDefinition containingBean) {
		String id = ele.getAttribute(ID_ATTRIBUTE);
		String nameAttr = ele.getAttribute(NAME_ATTRIBUTE);

		List aliases = new ArrayList();
		if (StringUtils.hasLength(nameAttr)) {
			String[] nameArr = StringUtils.tokenizeToStringArray(nameAttr, BEAN_NAME_DELIMITERS);
			aliases.addAll(Arrays.asList(nameArr));
		}

		String beanName = id;
		if (!StringUtils.hasText(beanName) && !aliases.isEmpty()) {
			beanName = (String) aliases.remove(0);
			if (logger.isDebugEnabled()) {
				logger.debug("No XML 'id' specified - using '" + beanName +
						"' as bean name and " + aliases + " as aliases");
			}
		}

		if (containingBean == null) {
			checkNameUniqueness(beanName, aliases, ele);
		}

		AbstractBeanDefinition beanDefinition = parseBeanDefinitionElement(ele, beanName, containingBean);
		if (beanDefinition != null) {
			if (!StringUtils.hasText(beanName)) {
				try {
					if (containingBean != null) {
						beanName = BeanDefinitionReaderUtils.generateBeanName(
								beanDefinition, this.readerContext.getRegistry(), true);
					}
					else {
						beanName = this.readerContext.generateBeanName(beanDefinition);
					}
					if (logger.isDebugEnabled()) {
						logger.debug("Neither XML 'id' nor 'name' specified - " +
								"using generated bean name [" + beanName + "]");
					}
				}
				catch (BeanDefinitionStoreException ex) {
					error(ex.getMessage(), ele);
					return null;
				}
			}
			String[] aliasesArray = StringUtils.toStringArray(aliases);
			return new BeanDefinitionHolder(beanDefinition, beanName, aliasesArray);
		}

		return null;
	}

	private void checkNameUniqueness(String beanName, List aliases, Element beanElement) {
		String foundName = null;

		if (StringUtils.hasText(beanName) && this.usedNames.contains(beanName)) {
			foundName = beanName;
		}
		if (foundName == null) {
			foundName = (String) CollectionUtils.findFirstMatch(this.usedNames, aliases);
		}
		if (foundName != null) {
			error("Bean name '" + foundName + "' is already used in this file.", beanElement);
		}

		this.usedNames.add(beanName);
		this.usedNames.addAll(aliases);
	}

	/**
	 * Parse the bean definition itself, without regard to name or aliases. May return
	 * <code>null</code> if problems occured during the parse of the bean definition.
	 */
	public AbstractBeanDefinition parseBeanDefinitionElement(
			Element ele, String beanName, BeanDefinition containingBean) {

		String className = null;
		if (ele.hasAttribute(CLASS_ATTRIBUTE)) {
			className = ele.getAttribute(CLASS_ATTRIBUTE).trim();