core/src/main/java/org/eclipse/gemini/blueprint/config/internal/ServiceBeanDefinitionParser.java - gemini.blueprint/org.eclipse.gemini.blueprint - Git at Google

 /******************************************************************************
  * Copyright (c) 2006, 2010 VMware Inc., Oracle Inc.
  * All rights reserved. This program and the accompanying materials
  * are made available under the terms of the Eclipse Public License v1.0
  * and Apache License v2.0 which accompanies this distribution.
  * The Eclipse Public License is available at
  * http://www.eclipse.org/legal/epl-v10.html and the Apache License v2.0
  * is available at http://www.opensource.org/licenses/apache2.0.php.
  * You may elect to redistribute this code under either of these licenses.
  *
  * Contributors:
  *   VMware Inc.
  *   Oracle Inc.
  *****************************************************************************/

 package org.eclipse.gemini.blueprint.config.internal;

 import java.util.Collection;
 import java.util.Locale;
 import java.util.Map;
 import java.util.Set;

 import org.eclipse.gemini.blueprint.config.internal.adapter.OsgiServiceRegistrationListenerAdapter;
 import org.eclipse.gemini.blueprint.config.internal.util.AttributeCallback;
 import org.eclipse.gemini.blueprint.config.internal.util.ParserUtils;
 import org.eclipse.gemini.blueprint.service.exporter.support.DefaultInterfaceDetector;
 import org.eclipse.gemini.blueprint.service.exporter.support.OsgiServiceFactoryBean;
 import org.springframework.beans.MutablePropertyValues;
 import org.springframework.beans.factory.BeanDefinitionStoreException;
 import org.springframework.beans.factory.config.BeanDefinition;
 import org.springframework.beans.factory.config.RuntimeBeanReference;
 import org.springframework.beans.factory.support.AbstractBeanDefinition;
 import org.springframework.beans.factory.support.BeanDefinitionBuilder;
 import org.springframework.beans.factory.support.BeanDefinitionRegistry;
 import org.springframework.beans.factory.support.ManagedList;
 import org.springframework.beans.factory.support.RootBeanDefinition;
 import org.springframework.beans.factory.xml.AbstractSingleBeanDefinitionParser;
 import org.springframework.beans.factory.xml.BeanDefinitionParserDelegate;
 import org.springframework.beans.factory.xml.ParserContext;
 import org.springframework.core.Conventions;
 import org.springframework.util.StringUtils;
 import org.springframework.util.xml.DomUtils;
 import org.w3c.dom.Attr;
 import org.w3c.dom.Document;
 import org.w3c.dom.Element;
 import org.w3c.dom.NamedNodeMap;
 import org.w3c.dom.Node;
 import org.w3c.dom.NodeList;

 /**
  * BeanDefinitionParser for service element found in the osgi namespace.
  *
  * @author Costin Leau
  * @author Hal Hildebrand
  * @author Andy Piper
  */
 public class ServiceBeanDefinitionParser extends AbstractSingleBeanDefinitionParser {

 	class ServiceAttributeCallback implements AttributeCallback {

 		public boolean process(Element parent, Attr attribute, BeanDefinitionBuilder bldr) {
 			String name = attribute.getLocalName();

 			if (INTERFACE.equals(name)) {
 				bldr.addPropertyValue(INTERFACES_PROP, attribute.getValue());
 				return false;
 			} else if (REF.equals(name)) {
 				return false;
 			}

 			else if (AUTOEXPORT.equals(name)) {
 				// convert constant to upper case to let Spring do the
 				// conversion
 				String label = attribute.getValue().toUpperCase(Locale.ENGLISH).replace('-', '_');
 				bldr.addPropertyValue(AUTOEXPORT_PROP, Enum.valueOf(DefaultInterfaceDetector.class, label));
 				return false;
 			}

 			else if (CONTEXT_CLASSLOADER.equals(name)) {
 				// convert constant to upper case to let Spring do the
 				// conversion

 				String value = attribute.getValue().toUpperCase(Locale.ENGLISH).replace('-', '_');
 				bldr.addPropertyValue(CCL_PROP, value);
 				return false;
 			}

 			return true;
 		}
 	}

 	// bean properties
 	private static final String TARGET_BEAN_NAME_PROP = "targetBeanName";

 	private static final String TARGET_PROP = "target";

 	private static final String LISTENERS_PROP = "listeners";

 	private static final String INTERFACES_PROP = "interfaces";

 	private static final String AUTOEXPORT_PROP = "interfaceDetector";

 	private static final String CCL_PROP = "exportContextClassLoader";
 	// XML elements
 	private static final String INTERFACES_ID = "interfaces";

 	private static final String INTERFACE = "interface";

 	private static final String PROPS_ID = "service-properties";

 	private static final String LISTENER = "registration-listener";

 	private static final String REF = "ref";

 	private static final String AUTOEXPORT = "auto-export";

 	private static final String CONTEXT_CLASSLOADER = "context-class-loader";

 	protected Class getBeanClass(Element element) {
 		return OsgiServiceFactoryBean.class;
 	}

 	protected void doParse(Element element, ParserContext parserContext, BeanDefinitionBuilder builder) {
 		builder.setRole(BeanDefinition.ROLE_INFRASTRUCTURE);
 		builder.getRawBeanDefinition().setSource(parserContext.extractSource(element));

 		OsgiDefaultsDefinition defaults = resolveDefaults(element.getOwnerDocument(), parserContext);

 		applyDefaults(parserContext, defaults, builder);

 		AttributeCallback callback = new ServiceAttributeCallback();
 		parseAttributes(element, builder, new AttributeCallback[] { callback }, defaults);

 		// determine nested/referred beans
 		Object target = null;
 		if (element.hasAttribute(REF))
 			target = new RuntimeBeanReference(element.getAttribute(REF));

 		// element is considered parent
 		NodeList nl = element.getChildNodes();

 		ManagedList listeners = new ManagedList();

 		// parse all sub elements
 		// we iterate through them since we have to 'catch' the possible nested
 		// bean which has an unknown name local name

 		for (int i = 0; i < nl.getLength(); i++) {
 			Node node = nl.item(i);
 			if (node instanceof Element) {
 				Element subElement = (Element) node;
 				String name = subElement.getLocalName();

 				// osgi:interface
 				if (parseInterfaces(element, subElement, parserContext, builder))
 					;
 				// osgi:service-properties
 				else if (parseServiceProperties(element, subElement, parserContext, builder))
 					;
 				// osgi:registration-listener
 				else if (LISTENER.equals(name)) {
 					BeanDefinition listenerDef = parseListener(parserContext, subElement, builder);
 					postProcessListenerDefinition(listenerDef);
 					listeners.add(listenerDef);
 				} else if (BeanDefinitionParserDelegate.DESCRIPTION_ELEMENT.equals(name)) {
 					builder.getRawBeanDefinition().setDescription(subElement.getTextContent());
 				}

 				// nested bean reference/declaration
 				else
 					target = parseBeanReference(element, subElement, parserContext, builder);
 			}
 		}

 		// if we have a named bean use target_bean_name (so we postpone the service creation)
 		if (target instanceof RuntimeBeanReference) {
 			builder.addPropertyValue(TARGET_BEAN_NAME_PROP, ((RuntimeBeanReference) target).getBeanName());
 		} else {
 			// add target (can be either an object instance or a bean
 			// definition)
 			builder.addPropertyValue(TARGET_PROP, target);
 		}

 		// add listeners
 		builder.addPropertyValue(LISTENERS_PROP, listeners);
 	}

 	protected void applyDefaults(ParserContext parserContext, OsgiDefaultsDefinition defaults,
 			BeanDefinitionBuilder builder) {
 		if (parserContext.isDefaultLazyInit()) {
 			// Default-lazy-init applies to custom bean definitions as well.
 			builder.setLazyInit(true);
 		}
 	}

 	protected void parseAttributes(Element element, BeanDefinitionBuilder builder, AttributeCallback[] callbacks,
 			OsgiDefaultsDefinition defaults) {

 		// parse attributes
 		ParserUtils.parseCustomAttributes(element, builder, callbacks);
 	}

 	/**
 	 * Get OSGi defaults (in case they haven't been resolved).
 	 *
 	 * @param document
 	 * @return
 	 */
 	protected OsgiDefaultsDefinition resolveDefaults(Document document, ParserContext parserContext) {
 		return new OsgiDefaultsDefinition(document, parserContext);
 	}

 	protected void postProcessListenerDefinition(BeanDefinition wrapperDef) {
 	}

 	// osgi:interfaces
 	private boolean parseInterfaces(Element parent, Element element, ParserContext parserContext,
 			BeanDefinitionBuilder builder) {
 		String name = element.getLocalName();

 		// osgi:interfaces
 		if (INTERFACES_ID.equals(name)) {
 			// check shortcut on the parent
 			if (parent.hasAttribute(INTERFACE)) {
 				parserContext.getReaderContext().error(
 						"either 'interface' attribute or <intefaces> sub-element has be specified", parent);
 			}
 			Set interfaces = parsePropertySetElement(parserContext, element, builder.getBeanDefinition());
 			builder.addPropertyValue(INTERFACES_PROP, interfaces);
 			return true;
 		}

 		return false;
 	}

 	// osgi:service-properties
 	private boolean parseServiceProperties(Element parent, Element element, ParserContext parserContext,
 			BeanDefinitionBuilder builder) {
 		String name = element.getLocalName();

 		if (PROPS_ID.equals(name)) {
 			Object props = null;
 			// check inlined ref
 			String ref = element.getAttribute(REF).trim();

 			boolean hasRef = StringUtils.hasText(ref);

 			if (DomUtils.getChildElementsByTagName(element, BeanDefinitionParserDelegate.ENTRY_ELEMENT).size() > 0) {
 				if (hasRef) {
 					parserContext.getReaderContext().error(
 							"Nested service properties definition cannot be used when attribute 'ref' is specified",
 							element);
 				} else {
 					props = parsePropertyMapElement(parserContext, element, builder.getRawBeanDefinition());
 				}
 			}

 			if (hasRef) {
 				props = new RuntimeBeanReference(ref);
 			}

 			if (props != null) {
 				builder.addPropertyValue(Conventions.attributeNameToPropertyName(PROPS_ID), props);
 			} else {
 				parserContext.getReaderContext().error("Invalid service property declaration", element);
 			}
 			return true;
 		}
 		return false;
 	}

 	// parse nested bean definition
 	private Object parseBeanReference(Element parent, Element element, ParserContext parserContext,
 			BeanDefinitionBuilder builder) {
 		// check shortcut on the parent
 		if (parent.hasAttribute(REF))
 			parserContext.getReaderContext().error(
 					"nested bean definition/reference cannot be used when attribute 'ref' is specified", parent);
 		return parsePropertySubElement(parserContext, element, builder.getBeanDefinition());
 	}

 	// osgi:listener
 	protected BeanDefinition parseListener(ParserContext context, Element element, BeanDefinitionBuilder builder) {

 		// filter elements
 		NodeList nl = element.getChildNodes();

 		// wrapped object
 		Object target = null;
 		// target bean name (used for cycles)
 		String targetName = null;

 		// discover if we have listener with ref and nested bean declaration
 		for (int i = 0; i < nl.getLength(); i++) {
 			Node node = nl.item(i);
 			if (node instanceof Element) {
 				Element nestedDefinition = (Element) node;
 				// check shortcut on the parent
 				if (element.hasAttribute(REF))
 					context.getReaderContext().error(
 							"nested bean declaration is not allowed if 'ref' attribute has been specified",
 							nestedDefinition);

 				target = parsePropertySubElement(context, nestedDefinition, builder.getBeanDefinition());
 				// if this is a bean reference (nested <ref>), extract the name
 				if (target instanceof RuntimeBeanReference) {
 					targetName = ((RuntimeBeanReference) target).getBeanName();
 				}
 			}
 		}

 		// extract registration/unregistration attributes from
 		// <osgi:registration-listener>
 		MutablePropertyValues vals = new MutablePropertyValues();

 		NamedNodeMap attrs = element.getAttributes();
 		for (int x = 0; x < attrs.getLength(); x++) {
 			Attr attribute = (Attr) attrs.item(x);
 			String name = attribute.getLocalName();

 			if (REF.equals(name))
 				targetName = attribute.getValue();
 			else {
 				vals.addPropertyValue(Conventions.attributeNameToPropertyName(name), attribute.getValue());
 			}

 		}

 		// create serviceListener wrapper
 		RootBeanDefinition wrapperDef = new RootBeanDefinition(OsgiServiceRegistrationListenerAdapter.class);

 		// set the target name (if we have one)
 		if (targetName != null) {
 			vals.addPropertyValue(TARGET_BEAN_NAME_PROP, targetName);
 		}
 		// else set the actual target
 		else {
 			vals.addPropertyValue(TARGET_PROP, target);
 		}

 		wrapperDef.setPropertyValues(vals);

 		return wrapperDef;

 	}

 	protected boolean shouldGenerateIdAsFallback() {
 		return true;
 	}

 	protected Object parsePropertySubElement(ParserContext context, Element beanDef, BeanDefinition beanDefinition) {
 		return context.getDelegate().parsePropertySubElement(beanDef, beanDefinition);
 	}

 	protected Set parsePropertySetElement(ParserContext context, Element beanDef, BeanDefinition beanDefinition) {
 		return context.getDelegate().parseSetElement(beanDef, beanDefinition);
 	}

 	protected Map parsePropertyMapElement(ParserContext context, Element beanDef, BeanDefinition beanDefinition) {
 		return context.getDelegate().parseMapElement(beanDef, beanDefinition);
 	}

 	protected void validateServiceReferences(Element element, String serviceId, ParserContext parserContext) {
 		BeanDefinitionRegistry registry = parserContext.getRegistry();
 		String[] names = registry.getBeanDefinitionNames();

 		for (String name : names) {
 			BeanDefinition definition = registry.getBeanDefinition(name);
 			Collection<String> exporters =
 					(Collection<String>) definition.getAttribute(ParserUtils.REFERENCE_LISTENER_REF_ATTR);

 			if (exporters != null && exporters.contains(serviceId)) {
 				parserContext.getReaderContext()
 						.error(
 								"Service exporter '" + serviceId + "' cannot be used as a reference listener by '"
 										+ name + "'", element);
 			}
 		}
 	}

 	@Override
 	protected String resolveId(Element element, AbstractBeanDefinition definition, ParserContext parserContext)
 			throws BeanDefinitionStoreException {

 		String id = super.resolveId(element, definition, parserContext);
 		validateServiceReferences(element, id, parserContext);
 		return id;
 	}
 }
	/******************************************************************************
	* Copyright (c) 2006, 2010 VMware Inc., Oracle Inc.
	* All rights reserved. This program and the accompanying materials
	* are made available under the terms of the Eclipse Public License v1.0
	* and Apache License v2.0 which accompanies this distribution.
	* The Eclipse Public License is available at
	* http://www.eclipse.org/legal/epl-v10.html and the Apache License v2.0
	* is available at http://www.opensource.org/licenses/apache2.0.php.
	* You may elect to redistribute this code under either of these licenses.
	*
	* Contributors:
	* VMware Inc.
	* Oracle Inc.
	*****************************************************************************/

	package org.eclipse.gemini.blueprint.config.internal;

	import java.util.Collection;
	import java.util.Locale;
	import java.util.Map;
	import java.util.Set;

	import org.eclipse.gemini.blueprint.config.internal.adapter.OsgiServiceRegistrationListenerAdapter;
	import org.eclipse.gemini.blueprint.config.internal.util.AttributeCallback;
	import org.eclipse.gemini.blueprint.config.internal.util.ParserUtils;
	import org.eclipse.gemini.blueprint.service.exporter.support.DefaultInterfaceDetector;
	import org.eclipse.gemini.blueprint.service.exporter.support.OsgiServiceFactoryBean;
	import org.springframework.beans.MutablePropertyValues;
	import org.springframework.beans.factory.BeanDefinitionStoreException;
	import org.springframework.beans.factory.config.BeanDefinition;
	import org.springframework.beans.factory.config.RuntimeBeanReference;
	import org.springframework.beans.factory.support.AbstractBeanDefinition;
	import org.springframework.beans.factory.support.BeanDefinitionBuilder;
	import org.springframework.beans.factory.support.BeanDefinitionRegistry;
	import org.springframework.beans.factory.support.ManagedList;
	import org.springframework.beans.factory.support.RootBeanDefinition;
	import org.springframework.beans.factory.xml.AbstractSingleBeanDefinitionParser;
	import org.springframework.beans.factory.xml.BeanDefinitionParserDelegate;
	import org.springframework.beans.factory.xml.ParserContext;
	import org.springframework.core.Conventions;
	import org.springframework.util.StringUtils;
	import org.springframework.util.xml.DomUtils;
	import org.w3c.dom.Attr;
	import org.w3c.dom.Document;
	import org.w3c.dom.Element;
	import org.w3c.dom.NamedNodeMap;
	import org.w3c.dom.Node;
	import org.w3c.dom.NodeList;

	/**
	* BeanDefinitionParser for service element found in the osgi namespace.
	*
	* @author Costin Leau
	* @author Hal Hildebrand
	* @author Andy Piper
	*/
	public class ServiceBeanDefinitionParser extends AbstractSingleBeanDefinitionParser {

	class ServiceAttributeCallback implements AttributeCallback {

	public boolean process(Element parent, Attr attribute, BeanDefinitionBuilder bldr) {
	String name = attribute.getLocalName();

	if (INTERFACE.equals(name)) {
	bldr.addPropertyValue(INTERFACES_PROP, attribute.getValue());
	return false;
	} else if (REF.equals(name)) {
	return false;
	}

	else if (AUTOEXPORT.equals(name)) {
	// convert constant to upper case to let Spring do the
	// conversion
	String label = attribute.getValue().toUpperCase(Locale.ENGLISH).replace('-', '_');
	bldr.addPropertyValue(AUTOEXPORT_PROP, Enum.valueOf(DefaultInterfaceDetector.class, label));
	return false;
	}

	else if (CONTEXT_CLASSLOADER.equals(name)) {
	// convert constant to upper case to let Spring do the
	// conversion

	String value = attribute.getValue().toUpperCase(Locale.ENGLISH).replace('-', '_');
	bldr.addPropertyValue(CCL_PROP, value);
	return false;
	}

	return true;
	}
	}

	// bean properties
	private static final String TARGET_BEAN_NAME_PROP = "targetBeanName";

	private static final String TARGET_PROP = "target";

	private static final String LISTENERS_PROP = "listeners";

	private static final String INTERFACES_PROP = "interfaces";

	private static final String AUTOEXPORT_PROP = "interfaceDetector";

	private static final String CCL_PROP = "exportContextClassLoader";
	// XML elements
	private static final String INTERFACES_ID = "interfaces";

	private static final String INTERFACE = "interface";

	private static final String PROPS_ID = "service-properties";

	private static final String LISTENER = "registration-listener";

	private static final String REF = "ref";

	private static final String AUTOEXPORT = "auto-export";

	private static final String CONTEXT_CLASSLOADER = "context-class-loader";

	protected Class getBeanClass(Element element) {
	return OsgiServiceFactoryBean.class;
	}

	protected void doParse(Element element, ParserContext parserContext, BeanDefinitionBuilder builder) {
	builder.setRole(BeanDefinition.ROLE_INFRASTRUCTURE);
	builder.getRawBeanDefinition().setSource(parserContext.extractSource(element));

	OsgiDefaultsDefinition defaults = resolveDefaults(element.getOwnerDocument(), parserContext);

	applyDefaults(parserContext, defaults, builder);

	AttributeCallback callback = new ServiceAttributeCallback();
	parseAttributes(element, builder, new AttributeCallback[] { callback }, defaults);

	// determine nested/referred beans
	Object target = null;
	if (element.hasAttribute(REF))
	target = new RuntimeBeanReference(element.getAttribute(REF));

	// element is considered parent
	NodeList nl = element.getChildNodes();

	ManagedList listeners = new ManagedList();

	// parse all sub elements
	// we iterate through them since we have to 'catch' the possible nested
	// bean which has an unknown name local name

	for (int i = 0; i < nl.getLength(); i++) {
	Node node = nl.item(i);
	if (node instanceof Element) {
	Element subElement = (Element) node;
	String name = subElement.getLocalName();

	// osgi:interface
	if (parseInterfaces(element, subElement, parserContext, builder))
	;
	// osgi:service-properties
	else if (parseServiceProperties(element, subElement, parserContext, builder))
	;
	// osgi:registration-listener
	else if (LISTENER.equals(name)) {
	BeanDefinition listenerDef = parseListener(parserContext, subElement, builder);
	postProcessListenerDefinition(listenerDef);
	listeners.add(listenerDef);
	} else if (BeanDefinitionParserDelegate.DESCRIPTION_ELEMENT.equals(name)) {
	builder.getRawBeanDefinition().setDescription(subElement.getTextContent());
	}

	// nested bean reference/declaration
	else
	target = parseBeanReference(element, subElement, parserContext, builder);
	}
	}

	// if we have a named bean use target_bean_name (so we postpone the service creation)
	if (target instanceof RuntimeBeanReference) {
	builder.addPropertyValue(TARGET_BEAN_NAME_PROP, ((RuntimeBeanReference) target).getBeanName());
	} else {
	// add target (can be either an object instance or a bean
	// definition)
	builder.addPropertyValue(TARGET_PROP, target);
	}

	// add listeners
	builder.addPropertyValue(LISTENERS_PROP, listeners);
	}

	protected void applyDefaults(ParserContext parserContext, OsgiDefaultsDefinition defaults,
	BeanDefinitionBuilder builder) {
	if (parserContext.isDefaultLazyInit()) {
	// Default-lazy-init applies to custom bean definitions as well.
	builder.setLazyInit(true);
	}
	}

	protected void parseAttributes(Element element, BeanDefinitionBuilder builder, AttributeCallback[] callbacks,
	OsgiDefaultsDefinition defaults) {

	// parse attributes
	ParserUtils.parseCustomAttributes(element, builder, callbacks);
	}

	/**
	* Get OSGi defaults (in case they haven't been resolved).
	*
	* @param document
	* @return
	*/
	protected OsgiDefaultsDefinition resolveDefaults(Document document, ParserContext parserContext) {
	return new OsgiDefaultsDefinition(document, parserContext);
	}

	protected void postProcessListenerDefinition(BeanDefinition wrapperDef) {
	}

	// osgi:interfaces
	private boolean parseInterfaces(Element parent, Element element, ParserContext parserContext,
	BeanDefinitionBuilder builder) {
	String name = element.getLocalName();

	// osgi:interfaces
	if (INTERFACES_ID.equals(name)) {
	// check shortcut on the parent
	if (parent.hasAttribute(INTERFACE)) {
	parserContext.getReaderContext().error(
	"either 'interface' attribute or <intefaces> sub-element has be specified", parent);
	}
	Set interfaces = parsePropertySetElement(parserContext, element, builder.getBeanDefinition());
	builder.addPropertyValue(INTERFACES_PROP, interfaces);
	return true;
	}

	return false;
	}

	// osgi:service-properties
	private boolean parseServiceProperties(Element parent, Element element, ParserContext parserContext,
	BeanDefinitionBuilder builder) {
	String name = element.getLocalName();

	if (PROPS_ID.equals(name)) {
	Object props = null;
	// check inlined ref
	String ref = element.getAttribute(REF).trim();

	boolean hasRef = StringUtils.hasText(ref);

	if (DomUtils.getChildElementsByTagName(element, BeanDefinitionParserDelegate.ENTRY_ELEMENT).size() > 0) {
	if (hasRef) {
	parserContext.getReaderContext().error(
	"Nested service properties definition cannot be used when attribute 'ref' is specified",
	element);
	} else {
	props = parsePropertyMapElement(parserContext, element, builder.getRawBeanDefinition());
	}
	}

	if (hasRef) {
	props = new RuntimeBeanReference(ref);
	}

	if (props != null) {
	builder.addPropertyValue(Conventions.attributeNameToPropertyName(PROPS_ID), props);
	} else {
	parserContext.getReaderContext().error("Invalid service property declaration", element);
	}
	return true;
	}
	return false;
	}

	// parse nested bean definition
	private Object parseBeanReference(Element parent, Element element, ParserContext parserContext,
	BeanDefinitionBuilder builder) {
	// check shortcut on the parent
	if (parent.hasAttribute(REF))
	parserContext.getReaderContext().error(
	"nested bean definition/reference cannot be used when attribute 'ref' is specified", parent);
	return parsePropertySubElement(parserContext, element, builder.getBeanDefinition());
	}

	// osgi:listener
	protected BeanDefinition parseListener(ParserContext context, Element element, BeanDefinitionBuilder builder) {

	// filter elements
	NodeList nl = element.getChildNodes();

	// wrapped object
	Object target = null;
	// target bean name (used for cycles)
	String targetName = null;

	// discover if we have listener with ref and nested bean declaration
	for (int i = 0; i < nl.getLength(); i++) {
	Node node = nl.item(i);
	if (node instanceof Element) {
	Element nestedDefinition = (Element) node;
	// check shortcut on the parent
	if (element.hasAttribute(REF))
	context.getReaderContext().error(
	"nested bean declaration is not allowed if 'ref' attribute has been specified",
	nestedDefinition);

	target = parsePropertySubElement(context, nestedDefinition, builder.getBeanDefinition());
	// if this is a bean reference (nested <ref>), extract the name
	if (target instanceof RuntimeBeanReference) {
	targetName = ((RuntimeBeanReference) target).getBeanName();
	}
	}
	}

	// extract registration/unregistration attributes from
	// <osgi:registration-listener>
	MutablePropertyValues vals = new MutablePropertyValues();

	NamedNodeMap attrs = element.getAttributes();
	for (int x = 0; x < attrs.getLength(); x++) {
	Attr attribute = (Attr) attrs.item(x);
	String name = attribute.getLocalName();

	if (REF.equals(name))
	targetName = attribute.getValue();
	else {
	vals.addPropertyValue(Conventions.attributeNameToPropertyName(name), attribute.getValue());
	}

	}

	// create serviceListener wrapper
	RootBeanDefinition wrapperDef = new RootBeanDefinition(OsgiServiceRegistrationListenerAdapter.class);

	// set the target name (if we have one)
	if (targetName != null) {
	vals.addPropertyValue(TARGET_BEAN_NAME_PROP, targetName);
	}
	// else set the actual target
	else {
	vals.addPropertyValue(TARGET_PROP, target);
	}

	wrapperDef.setPropertyValues(vals);

	return wrapperDef;

	}

	protected boolean shouldGenerateIdAsFallback() {
	return true;
	}

	protected Object parsePropertySubElement(ParserContext context, Element beanDef, BeanDefinition beanDefinition) {
	return context.getDelegate().parsePropertySubElement(beanDef, beanDefinition);
	}

	protected Set parsePropertySetElement(ParserContext context, Element beanDef, BeanDefinition beanDefinition) {
	return context.getDelegate().parseSetElement(beanDef, beanDefinition);
	}

	protected Map parsePropertyMapElement(ParserContext context, Element beanDef, BeanDefinition beanDefinition) {
	return context.getDelegate().parseMapElement(beanDef, beanDefinition);
	}

	protected void validateServiceReferences(Element element, String serviceId, ParserContext parserContext) {
	BeanDefinitionRegistry registry = parserContext.getRegistry();
	String[] names = registry.getBeanDefinitionNames();

	for (String name : names) {
	BeanDefinition definition = registry.getBeanDefinition(name);
	Collection<String> exporters =
	(Collection<String>) definition.getAttribute(ParserUtils.REFERENCE_LISTENER_REF_ATTR);

	if (exporters != null && exporters.contains(serviceId)) {
	parserContext.getReaderContext()
	.error(
	"Service exporter '" + serviceId + "' cannot be used as a reference listener by '"
	+ name + "'", element);
	}
	}
	}

	@Override
	protected String resolveId(Element element, AbstractBeanDefinition definition, ParserContext parserContext)
	throws BeanDefinitionStoreException {

	String id = super.resolveId(element, definition, parserContext);
	validateServiceReferences(element, id, parserContext);
	return id;
	}
	}