configbeandefinitionparser.java

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			List pointcuts = DomUtils.getChildElementsByTagName(aspectElement, POINTCUT);
			for (int i = 0; i < pointcuts.size(); i++) {
				Element pointcutElement = (Element) pointcuts.get(i);
				parsePointcut(pointcutElement, parserContext);
			}

			parserContext.popAndRegisterContainingComponent();
		}
		finally {
			this.parseState.pop();
		}
	}

	private AspectComponentDefinition createAspectComponentDefinition(
			Element aspectElement, String aspectId, List beanDefs, List beanRefs, ParserContext parserContext) {

		BeanDefinition[] beanDefArray = (BeanDefinition[]) beanDefs.toArray(new BeanDefinition[beanDefs.size()]);
		BeanReference[] beanRefArray = (BeanReference[]) beanRefs.toArray(new BeanReference[beanRefs.size()]);
		Object source = parserContext.extractSource(aspectElement);
		return new AspectComponentDefinition(aspectId, beanDefArray, beanRefArray, source);
	}

	/**
	 * Return <code>true</code> if the supplied node describes an advice type. May be one of:
	 * '<code>before</code>', '<code>after</code>', '<code>after-returning</code>',
	 * '<code>after-throwing</code>' or '<code>around</code>'.
	 */
	private boolean isAdviceNode(Node aNode) {
		if (!(aNode instanceof Element)) {
			return false;
		}
		else {
			String name = aNode.getLocalName();
			return (BEFORE.equals(name) || AFTER.equals(name) || AFTER_RETURNING_ELEMENT.equals(name) ||
					AFTER_THROWING_ELEMENT.equals(name) || AROUND.equals(name));
		}
	}

	/**
	 * Parse a '<code>declare-parents</code>' element and register the appropriate
	 * DeclareParentsAdvisor with the BeanDefinitionRegistry encapsulated in the
	 * supplied ParserContext.
	 */
	private AbstractBeanDefinition parseDeclareParents(Element declareParentsElement, ParserContext parserContext) {
		BeanDefinitionBuilder builder = BeanDefinitionBuilder.rootBeanDefinition(DeclareParentsAdvisor.class);
		builder.addConstructorArg(declareParentsElement.getAttribute(IMPLEMENT_INTERFACE));
		builder.addConstructorArg(declareParentsElement.getAttribute(TYPE_PATTERN));
		builder.addConstructorArg(declareParentsElement.getAttribute(DEFAULT_IMPL));
		builder.setSource(parserContext.extractSource(declareParentsElement));
		AbstractBeanDefinition definition = builder.getBeanDefinition();
		parserContext.getReaderContext().registerWithGeneratedName(definition);
		return definition;
	}

	/**
	 * Parses one of '<code>before</code>', '<code>after</code>', '<code>after-returning</code>',
	 * '<code>after-throwing</code>' or '<code>around</code>' and registers the resulting
	 * BeanDefinition with the supplied BeanDefinitionRegistry.
	 * @return the generated advice RootBeanDefinition
	 */
	private AbstractBeanDefinition parseAdvice(
			String aspectName, int order, Element aspectElement, Element adviceElement, ParserContext parserContext,
			List beanDefinitions, List beanReferences) {

		try {
			this.parseState.push(new AdviceEntry(adviceElement.getLocalName()));

			// create the method factory bean
			RootBeanDefinition methodDefinition = new RootBeanDefinition(MethodLocatingFactoryBean.class);
			methodDefinition.getPropertyValues().addPropertyValue("targetBeanName", aspectName);
			methodDefinition.getPropertyValues().addPropertyValue("methodName", adviceElement.getAttribute("method"));
			methodDefinition.setSynthetic(true);

			// create instance factory definition
			RootBeanDefinition aspectFactoryDef =
					new RootBeanDefinition(SimpleBeanFactoryAwareAspectInstanceFactory.class);
			aspectFactoryDef.getPropertyValues().addPropertyValue("aspectBeanName", aspectName);
			aspectFactoryDef.setSynthetic(true);

			// register the pointcut
			AbstractBeanDefinition adviceDef = createAdviceDefinition(
					adviceElement, parserContext, aspectName, order, methodDefinition, aspectFactoryDef,
					beanDefinitions, beanReferences);

			// configure the advisor
			RootBeanDefinition advisorDefinition = new RootBeanDefinition(AspectJPointcutAdvisor.class);
			advisorDefinition.setSource(parserContext.extractSource(adviceElement));
			advisorDefinition.getConstructorArgumentValues().addGenericArgumentValue(adviceDef);
			if (aspectElement.hasAttribute(ORDER_PROPERTY)) {
				advisorDefinition.getPropertyValues().addPropertyValue(
						ORDER_PROPERTY, aspectElement.getAttribute(ORDER_PROPERTY));
			}

			// register the final advisor
			parserContext.getReaderContext().registerWithGeneratedName(advisorDefinition);

			return advisorDefinition;
		}
		finally {
			this.parseState.pop();
		}
	}

	/**
	 * Creates the RootBeanDefinition for a POJO advice bean. Also causes pointcut
	 * parsing to occur so that the pointcut may be associate with the advice bean.
	 * This same pointcut is also configured as the pointcut for the enclosing
	 * Advisor definition using the supplied MutablePropertyValues.
	 */
	private AbstractBeanDefinition createAdviceDefinition(
			Element adviceElement, ParserContext parserContext, String aspectName, int order,
			RootBeanDefinition methodDef, RootBeanDefinition aspectFactoryDef, List beanDefinitions, List beanReferences) {

		RootBeanDefinition adviceDefinition = new RootBeanDefinition(getAdviceClass(adviceElement));
		adviceDefinition.setSource(parserContext.extractSource(adviceElement));

		adviceDefinition.getPropertyValues().addPropertyValue(
				ASPECT_NAME_PROPERTY, aspectName);
		adviceDefinition.getPropertyValues().addPropertyValue(
				DECLARATION_ORDER_PROPERTY, new Integer(order));

		if (adviceElement.hasAttribute(RETURNING)) {
			adviceDefinition.getPropertyValues().addPropertyValue(
					RETURNING_PROPERTY, adviceElement.getAttribute(RETURNING));
		}
		if (adviceElement.hasAttribute(THROWING)) {
			adviceDefinition.getPropertyValues().addPropertyValue(
					THROWING_PROPERTY, adviceElement.getAttribute(THROWING));
		}
		if (adviceElement.hasAttribute(ARG_NAMES)) {
			adviceDefinition.getPropertyValues().addPropertyValue(
					ARG_NAMES_PROPERTY, adviceElement.getAttribute(ARG_NAMES));
		}

		ConstructorArgumentValues cav = adviceDefinition.getConstructorArgumentValues();
		cav.addIndexedArgumentValue(METHOD_INDEX, methodDef);

		Object pointcut = parsePointcutProperty(adviceElement, parserContext);
		if (pointcut instanceof BeanDefinition) {
			cav.addIndexedArgumentValue(POINTCUT_INDEX, pointcut);
			beanDefinitions.add(pointcut);
		}
		else if (pointcut instanceof String) {
			RuntimeBeanReference pointcutRef = new RuntimeBeanReference((String) pointcut);
			cav.addIndexedArgumentValue(POINTCUT_INDEX, pointcutRef);
			beanReferences.add(pointcutRef);
		}

		cav.addIndexedArgumentValue(ASPECT_INSTANCE_FACTORY_INDEX, aspectFactoryDef);

		return adviceDefinition;
	}

	/**
	 * Gets the advice implementation class corresponding to the supplied {@link Element}.
	 */
	private Class getAdviceClass(Element adviceElement) {
		String elementName = adviceElement.getLocalName();
		if (BEFORE.equals(elementName)) {
			return AspectJMethodBeforeAdvice.class;
		}
		else if (AFTER.equals(elementName)) {
			return AspectJAfterAdvice.class;
		}
		else if (AFTER_RETURNING_ELEMENT.equals(elementName)) {
			return AspectJAfterReturningAdvice.class;
		}
		else if (AFTER_THROWING_ELEMENT.equals(elementName)) {
			return AspectJAfterThrowingAdvice.class;
		}
		else if (AROUND.equals(elementName)) {
			return AspectJAroundAdvice.class;
		}
		else {
			throw new IllegalArgumentException("Unknown advice kind [" + elementName + "].");
		}
	}

	/**
	 * Parses the supplied <code>&lt;pointcut&gt;</code> and registers the resulting
	 * Pointcut with the BeanDefinitionRegistry.
	 */
	private AbstractBeanDefinition parsePointcut(Element pointcutElement, ParserContext parserContext) {
		String id = pointcutElement.getAttribute(ID);
		String expression = pointcutElement.getAttribute(EXPRESSION);

		AbstractBeanDefinition pointcutDefinition = null;
		
		try {
			this.parseState.push(new PointcutEntry(id));
			pointcutDefinition = createPointcutDefinition(expression);
			pointcutDefinition.setSource(parserContext.extractSource(pointcutElement));

			String pointcutBeanName = id;
			if (StringUtils.hasText(pointcutBeanName)) {
				parserContext.getRegistry().registerBeanDefinition(pointcutBeanName, pointcutDefinition);
			}
			else {
				pointcutBeanName = parserContext.getReaderContext().registerWithGeneratedName(pointcutDefinition);
			}

			parserContext.registerComponent(
					new PointcutComponentDefinition(pointcutBeanName, pointcutDefinition, expression));
		}
		finally {
			this.parseState.pop();
		}

		return pointcutDefinition;
	}

	/**
	 * Parses the <code>pointcut</code> or <code>pointcut-ref</code> attributes of the supplied
	 * {@link Element} and add a <code>pointcut</code> property as appropriate. Generates a
	 * {@link org.springframework.beans.factory.config.BeanDefinition} for the pointcut if  necessary
	 * and returns its bean name, otherwise returns the bean name of the referred pointcut.
	 */
	private Object parsePointcutProperty(Element element, ParserContext parserContext) {
		if (element.hasAttribute(POINTCUT) && element.hasAttribute(POINTCUT_REF)) {
			parserContext.getReaderContext().error(
					"Cannot define both 'pointcut' and 'pointcut-ref' on <advisor> tag.",
					element, this.parseState.snapshot());
			return null;
		}
		else if (element.hasAttribute(POINTCUT)) {
			// Create a pointcut for the anonymous pc and register it.
			String expression = element.getAttribute(POINTCUT);
			AbstractBeanDefinition pointcutDefinition = createPointcutDefinition(expression);
			pointcutDefinition.setSource(parserContext.extractSource(element));
			return pointcutDefinition;
		}
		else if (element.hasAttribute(POINTCUT_REF)) {
			String pointcutRef = element.getAttribute(POINTCUT_REF);
			if (!StringUtils.hasText(pointcutRef)) {
				parserContext.getReaderContext().error(
						"'pointcut-ref' attribute contains empty value.", element, this.parseState.snapshot());
				return null;
			}
			return pointcutRef;
		}
		else {
			parserContext.getReaderContext().error(
					"Must define one of 'pointcut' or 'pointcut-ref' on <advisor> tag.",
					element, this.parseState.snapshot());
			return null;
		}
	}

	/**
	 * Creates a {@link BeanDefinition} for the {@link AspectJExpressionPointcut} class using
	 * the supplied pointcut expression.
	 */
	protected AbstractBeanDefinition createPointcutDefinition(String expression) {
		RootBeanDefinition beanDefinition = new RootBeanDefinition(AspectJExpressionPointcut.class);
		beanDefinition.setSingleton(false);
		beanDefinition.setSynthetic(true);
		beanDefinition.getPropertyValues().addPropertyValue(EXPRESSION, expression);
		return beanDefinition;
	}

}