DispatchType now caches the DispatcherTypeProvider list on a per requ…

…est basis

config-servlet/src/main/java/org/ocpsoft/rewrite/servlet/config/DispatchType.java

@@ -37,18 +37,13 @@
  */
 public class DispatchType extends HttpCondition
 {
+ private final static String PROVIDER_KEY = DispatchType.class.getName() + "_PROVIDERS";
+
  private final DispatcherType type;
- private final List<DispatcherTypeProvider> providers;
 
  private DispatchType(final DispatcherType type)
  {
  this.type = type;
-
- // for performance reasons only create the list of providers once
- providers = Iterators.asList(
- ServiceLoader.loadTypesafe(DispatcherTypeProvider.class).iterator());
- Collections.sort(providers, new WeightedComparator());
-
  }
 
  @Override
@@ -66,7 +61,7 @@ public boolean evaluateHttp(final HttpServletRewrite event, final EvaluationCont
  */
  private DispatcherType getDispatcherType(final HttpServletRewrite event)
  {
- for (DispatcherTypeProvider provider : providers) {
+ for (DispatcherTypeProvider provider : getDispatcherTypeProviders(event)) {
  DispatcherType dispatcherType = provider.getDispatcherType(event.getRequest(), event.getServletContext());
  if (dispatcherType != null) {
  return dispatcherType;
@@ -75,6 +70,22 @@ private DispatcherType getDispatcherType(final HttpServletRewrite event)
  throw new IllegalStateException("Unable to determine dispatcher type of current request");
  }
 
+ /**
+ * Simple caching mechanism for the providers on a per request basis
+ */
+ @SuppressWarnings("unchecked")
+ private List<DispatcherTypeProvider> getDispatcherTypeProviders(HttpServletRewrite event)
+ {
+ List<DispatcherTypeProvider> providers = (List<DispatcherTypeProvider>)
+ event.getRequest().getAttribute(PROVIDER_KEY);
+ if (providers == null) {
+ providers = Iterators.asList(ServiceLoader.loadTypesafe(DispatcherTypeProvider.class).iterator());
+ Collections.sort(providers, new WeightedComparator());
+ event.getRequest().setAttribute(PROVIDER_KEY, providers);
+ }
+ return providers;
+ }
+
  /**
  * Create a {@link DispatchType} condition that ensures the current {@link HttpServletRewrite} is a
  * {@link DispatcherType#FORWARD}