SpringSecurity的Filter执行顺序在源码中的体现

/**
* An internal use only {@link Comparator} that sorts the Security {@link Filter}
* instances to ensure they are in the correct order.
*
* @author Rob Winch
* @since 3.2
*/@SuppressWarnings("serial")
final class FilterComparator implements Comparator<Filter>, Serializable {
private static final int STEP = ;
private Map<String, Integer> filterToOrder = new HashMap<String, Integer>(); FilterComparator() {
int order = ;
put(ChannelProcessingFilter.class, order);
order += STEP;
put(ConcurrentSessionFilter.class, order);
order += STEP;
put(WebAsyncManagerIntegrationFilter.class, order);
order += STEP;
put(SecurityContextPersistenceFilter.class, order);
order += STEP;
put(HeaderWriterFilter.class, order);
order += STEP;
put(CsrfFilter.class, order);
order += STEP;
put(LogoutFilter.class, order);
order += STEP;
put(X509AuthenticationFilter.class, order);
order += STEP;
put(AbstractPreAuthenticatedProcessingFilter.class, order);
order += STEP;
filterToOrder.put("org.springframework.security.cas.web.CasAuthenticationFilter",
order);
order += STEP;
put(UsernamePasswordAuthenticationFilter.class, order);
order += STEP;
put(ConcurrentSessionFilter.class, order);
order += STEP;
filterToOrder.put(
"org.springframework.security.openid.OpenIDAuthenticationFilter", order);
order += STEP;
put(DefaultLoginPageGeneratingFilter.class, order);
order += STEP;
put(ConcurrentSessionFilter.class, order);
order += STEP;
put(DigestAuthenticationFilter.class, order);
order += STEP;
put(BasicAuthenticationFilter.class, order);
order += STEP;
put(RequestCacheAwareFilter.class, order);
order += STEP;
put(SecurityContextHolderAwareRequestFilter.class, order);
order += STEP;
put(JaasApiIntegrationFilter.class, order);
order += STEP;
put(RememberMeAuthenticationFilter.class, order);
order += STEP;
put(AnonymousAuthenticationFilter.class, order);
order += STEP;
put(SessionManagementFilter.class, order);
order += STEP;
put(ExceptionTranslationFilter.class, order);
order += STEP;
put(FilterSecurityInterceptor.class, order);
order += STEP;
put(SwitchUserFilter.class, order);
} public int compare(Filter lhs, Filter rhs) {
Integer left = getOrder(lhs.getClass());
Integer right = getOrder(rhs.getClass());
return left - right;
} /**
* Determines if a particular {@link Filter} is registered to be sorted
*
* @param filter
* @return
*/
public boolean isRegistered(Class<? extends Filter> filter) {
return getOrder(filter) != null;
} /**
* Registers a {@link Filter} to exist after a particular {@link Filter} that is
* already registered.
* @param filter the {@link Filter} to register
* @param afterFilter the {@link Filter} that is already registered and that
* {@code filter} should be placed after.
*/
public void registerAfter(Class<? extends Filter> filter,
Class<? extends Filter> afterFilter) {
Integer position = getOrder(afterFilter);
if (position == null) {
throw new IllegalArgumentException(
"Cannot register after unregistered Filter " + afterFilter);
} put(filter, position + );
} /**
* Registers a {@link Filter} to exist before a particular {@link Filter} that is
* already registered.
* @param filter the {@link Filter} to register
* @param beforeFilter the {@link Filter} that is already registered and that
* {@code filter} should be placed before.
*/
public void registerBefore(Class<? extends Filter> filter,
Class<? extends Filter> beforeFilter) {
Integer position = getOrder(beforeFilter);
if (position == null) {
throw new IllegalArgumentException(
"Cannot register after unregistered Filter " + beforeFilter);
} put(filter, position - );
} private void put(Class<? extends Filter> filter, int position) {
String className = filter.getName();
filterToOrder.put(className, position);
} /**
* Gets the order of a particular {@link Filter} class taking into consideration
* superclasses.
*
* @param clazz the {@link Filter} class to determine the sort order
* @return the sort order or null if not defined
*/
private Integer getOrder(Class<?> clazz) {
while (clazz != null) {
Integer result = filterToOrder.get(clazz.getName());
if (result != null) {
return result;
}
clazz = clazz.getSuperclass();
}
return null;
}
}