config/src/main/java/org/springframework/security/config/http/HttpSecurityBeanDefinitionParser.java
@SuppressWarnings({ "unchecked" })
	@Override
	public BeanDefinition parse(Element element, ParserContext pc) {
		CompositeComponentDefinition compositeDef = new CompositeComponentDefinition(
				element.getTagName(), pc.extractSource(element));
		pc.pushContainingComponent(compositeDef);

		registerFilterChainProxyIfNecessary(pc, pc.extractSource(element));

		// Obtain the filter chains and add the new chain to it
		BeanDefinition listFactoryBean = pc.getRegistry().getBeanDefinition(
				BeanIds.FILTER_CHAINS);
		List<BeanReference> filterChains = (List<BeanReference>) listFactoryBean
				.getPropertyValues().getPropertyValue("sourceList").getValue();

		filterChains.add(createFilterChain(element, pc));

		pc.popAndRegisterContainingComponent();
		return null;
	}
@SuppressWarnings({ "unchecked" })
	@Override
	public BeanDefinition parse(Element element, ParserContext pc) {
		CompositeComponentDefinition compositeDef = new CompositeComponentDefinition(
				element.getTagName(), pc.extractSource(element));
		pc.pushContainingComponent(compositeDef);

		registerFilterChainProxyIfNecessary(pc, pc.extractSource(element));

		// Obtain the filter chains and add the new chain to it
		BeanDefinition listFactoryBean = pc.getRegistry().getBeanDefinition(
				BeanIds.FILTER_CHAINS);
		List<BeanReference> filterChains = (List<BeanReference>) listFactoryBean
				.getPropertyValues().getPropertyValue("sourceList").getValue();

		filterChains.add(createFilterChain(element, pc));

		pc.popAndRegisterContainingComponent();
		return null;
	}
The aim of this method is to build the list of filters which have been defined by
the namespace elements and attributes within the &lt;http&gt; configuration, along
with any custom-filter's linked to user-defined filter beans.
<p>
By the end of this method, the default <tt>FilterChainProxy</tt> bean should have
been registered and will have the map of filter chains defined, with the
"universal" match pattern mapped to the list of beans which have been parsed here.