diff --git a/apis/rackspace-cloudfiles/src/main/java/org/jclouds/rackspace/cloudfiles/v1/CloudFilesApi.java b/apis/rackspace-cloudfiles/src/main/java/org/jclouds/rackspace/cloudfiles/v1/CloudFilesApi.java
index 2a0e50dd37..ff19eb897c 100644
--- a/apis/rackspace-cloudfiles/src/main/java/org/jclouds/rackspace/cloudfiles/v1/CloudFilesApi.java
+++ b/apis/rackspace-cloudfiles/src/main/java/org/jclouds/rackspace/cloudfiles/v1/CloudFilesApi.java
@@ -16,7 +16,6 @@
  */
 package org.jclouds.rackspace.cloudfiles.v1;
 
-import org.jclouds.javax.annotation.Nullable;
 import org.jclouds.openstack.swift.v1.SwiftApi;
 import org.jclouds.rackspace.cloudfiles.v1.features.CDNApi;
 import org.jclouds.rackspace.cloudfiles.v1.functions.RegionToCDNEndpoint;
@@ -47,7 +46,7 @@ public interface CloudFilesApi extends SwiftApi {
     * @return the {@link CDNApi} for the specified region.
     */
    @Delegate
-   CDNApi getCDNApi(@EndpointParam(parser = RegionToCDNEndpoint.class) @Nullable String region);
+   CDNApi getCDNApi(@EndpointParam(parser = RegionToCDNEndpoint.class) String region);
 
    /**
     * Provides access to Cloud Files CDN features.
@@ -60,5 +59,5 @@ public interface CloudFilesApi extends SwiftApi {
     */
    @Deprecated
    @Delegate
-   CDNApi cdnApiInRegion(@EndpointParam(parser = RegionToCDNEndpoint.class) @Nullable String region);
+   CDNApi cdnApiInRegion(@EndpointParam(parser = RegionToCDNEndpoint.class) String region);
 }
diff --git a/apis/rackspace-cloudfiles/src/main/java/org/jclouds/rackspace/cloudfiles/v1/features/CDNApi.java b/apis/rackspace-cloudfiles/src/main/java/org/jclouds/rackspace/cloudfiles/v1/features/CDNApi.java
index 27a9e8cbb5..e88626f57e 100644
--- a/apis/rackspace-cloudfiles/src/main/java/org/jclouds/rackspace/cloudfiles/v1/features/CDNApi.java
+++ b/apis/rackspace-cloudfiles/src/main/java/org/jclouds/rackspace/cloudfiles/v1/features/CDNApi.java
@@ -39,7 +39,6 @@ import org.jclouds.Fallbacks.FalseOnNotFoundOr404;
 import org.jclouds.Fallbacks.NullOnNotFoundOr404;
 import org.jclouds.javax.annotation.Nullable;
 import org.jclouds.openstack.keystone.v2_0.filters.AuthenticateRequest;
-import org.jclouds.rackspace.cloudfiles.v1.CloudFilesApi;
 import org.jclouds.rackspace.cloudfiles.v1.binders.BindCDNPurgeEmailAddressesToHeaders;
 import org.jclouds.rackspace.cloudfiles.v1.domain.CDNContainer;
 import org.jclouds.rackspace.cloudfiles.v1.functions.ParseCDNContainerFromHeaders;
@@ -60,12 +59,12 @@ import com.google.common.collect.FluentIterable;
  * Provides access to the Rackspace Cloud Files CDN API features.
  *
  * <h3>NOTE</h3>
- * Before a container can be CDN enabled, it must exist in the storage system. 
- * To CDN enable the container, perform PUT request against it using the <code>publicURL</code> 
- * noted in the service catalog for Cloud Files during Authentication and set the 
+ * Before a container can be CDN enabled, it must exist in the storage system.
+ * To CDN enable the container, perform PUT request against it using the <code>publicURL</code>
+ * noted in the service catalog for Cloud Files during Authentication and set the
  * <code>X-CDN-Enabled</code> header to <code>true</code>.
- * 
- * @see {@link CloudFilesApi#getCDNApiForRegion(String)}
+ *
+ * @see {@link org.jclouds.rackspace.cloudfiles.v1.CloudFilesApi#getCDNApi(String)}
  */
 @Beta
 @RequestFilters(AuthenticateRequest.class)
@@ -74,7 +73,7 @@ public interface CDNApi extends Closeable {
 
    /**
     * Lists up to 10,000 CDN containers.
-    * 
+    *
     * @return a list of CDN enabled containers ordered by name.
     */
    @Named("cdn:list")
@@ -86,10 +85,10 @@ public interface CDNApi extends Closeable {
 
    /**
     * Lists CDN containers, with the given options.
-    * 
+    *
     * @param options
     *           the options to control output.
-    * 
+    *
     * @return a list of CDN enabled containers ordered by name.
     */
    @Named("cdn:list")
@@ -101,10 +100,10 @@ public interface CDNApi extends Closeable {
 
    /**
     * Gets the specified CDN Container.
-    * 
+    *
     * @param containerName
     *           the name of the CDN Container
-    * 
+    *
     * @return the CDNContainer or null, if not found.
     */
    @Named("cdn:get")
@@ -117,10 +116,10 @@ public interface CDNApi extends Closeable {
 
    /**
     * Enables the {@link CDNContainer}.
-    * 
+    *
     * @param containerName
     *           corresponds to {@link CDNContainer#getName()}.
-    *           
+    *
     * @return the CDN container {@link URI} or {@code null}, if not found.
     */
    @Named("cdn:enable")
@@ -134,12 +133,12 @@ public interface CDNApi extends Closeable {
 
    /**
     * Enables the {@link CDNContainer} with a TTL.
-    * 
+    *
     * @param containerName
     *           corresponds to {@link CDNContainer#getName()}.
     * @param ttl
     *           the TTL for the CDN Container.
-    *           
+    *
     * @return the CDN container {@link URI} or {@code null}, if not found.
     */
    @Named("cdn:enable")
@@ -149,15 +148,15 @@ public interface CDNApi extends Closeable {
    @Path("/{containerName}")
    @Headers(keys = CDN_ENABLED, values = "true")
    @Nullable
-   URI enable(@PathParam("containerName") String containerName, 
+   URI enable(@PathParam("containerName") String containerName,
          @HeaderParam(CDN_TTL) int ttl);
 
    /**
     * Disables the {@link CDNContainer}.
-    * 
+    *
     * @param containerName
     *           corresponds to {@link CDNContainer#getName()}.
-    *           
+    *
     * @return {@code true} if the container was disabled, {@code false} if not.
     */
    @Named("cdn:disable")
@@ -169,14 +168,14 @@ public interface CDNApi extends Closeable {
 
    /**
     * Purges an object from the CDN.
-    * 
+    *
     * @param containerName
     *           corresponds to {@link CDNContainer#getName()}.
     * @param objectName
     *           the object in the {@link CDNContainer} to purge.
     * @param emails
     *           the email addresses to notify after purging.
-    * 
+    *
     * @return {@code true} if the object was successfully purged, {@code false} if not.
     */
    @Named("cdn:purge")
@@ -184,16 +183,16 @@ public interface CDNApi extends Closeable {
    @Fallback(FalseOnNotFoundOr404.class)
    @Path("/{containerName}/{objectName}")
    @Headers(keys = CloudFilesHeaders.CDN_PURGE_OBJECT_EMAIL, values = "{email}")
-   boolean purgeObject(@PathParam("containerName") String containerName, 
-         @PathParam("objectName") String objectName, 
+   boolean purgeObject(@PathParam("containerName") String containerName,
+         @PathParam("objectName") String objectName,
          @BinderParam(BindCDNPurgeEmailAddressesToHeaders.class) Iterable<String> emails);
 
    /**
     * Updates a CDN container with the supplied {@link UpdateCDNContainerOptions} options.
-    * 
+    *
     * @param containerName
     *           corresponds to {@link CDNContainer#getName()}.
-    *           
+    *
     * @param options
     *           the {@link UpdateCDNContainerOptions} options.
     */
diff --git a/apis/rackspace-cloudfiles/src/main/java/org/jclouds/rackspace/cloudfiles/v1/functions/ParseCDNContainerFromHeaders.java b/apis/rackspace-cloudfiles/src/main/java/org/jclouds/rackspace/cloudfiles/v1/functions/ParseCDNContainerFromHeaders.java
index 3d4e0f9773..38430d62dc 100644
--- a/apis/rackspace-cloudfiles/src/main/java/org/jclouds/rackspace/cloudfiles/v1/functions/ParseCDNContainerFromHeaders.java
+++ b/apis/rackspace-cloudfiles/src/main/java/org/jclouds/rackspace/cloudfiles/v1/functions/ParseCDNContainerFromHeaders.java
@@ -57,11 +57,11 @@ public class ParseCDNContainerFromHeaders implements Function<HttpResponse, CDNC
       String enabled = checkNotNull(from.getFirstHeaderOrNull(CDN_ENABLED), CDN_ENABLED);
       String logRetention = checkNotNull(from.getFirstHeaderOrNull(CDN_LOG_RETENTION), CDN_LOG_RETENTION);
       String ttl = checkNotNull(from.getFirstHeaderOrNull(CDN_TTL), CDN_TTL);
-      
+
       // just need the name from the path
       List<String> parts = newArrayList(Splitter.on('/').split(request.getEndpoint().getPath()));
-      checkArgument(parts.size() > 0);
-      
+      checkArgument(!parts.isEmpty());
+
       return CDNContainer.builder().name(parts.get(parts.size() - 1))
             .enabled(Boolean.parseBoolean(enabled))
             .logRetention(Boolean.parseBoolean(logRetention))
diff --git a/apis/rackspace-cloudfiles/src/main/java/org/jclouds/rackspace/cloudfiles/v1/functions/RegionToCDNEndpoint.java b/apis/rackspace-cloudfiles/src/main/java/org/jclouds/rackspace/cloudfiles/v1/functions/RegionToCDNEndpoint.java
index 866c34f753..07f6f250a2 100644
--- a/apis/rackspace-cloudfiles/src/main/java/org/jclouds/rackspace/cloudfiles/v1/functions/RegionToCDNEndpoint.java
+++ b/apis/rackspace-cloudfiles/src/main/java/org/jclouds/rackspace/cloudfiles/v1/functions/RegionToCDNEndpoint.java
@@ -34,15 +34,15 @@ import com.google.common.base.Function;
 import com.google.common.base.Supplier;
 
 /**
- * This class ensures that the correct Cloud Files CDN endpoint is retrieved from the endpoint 
- * supplier. The CDN API should never be instantiated directly, but rather accessed through the 
+ * This class ensures that the correct Cloud Files CDN endpoint is retrieved from the endpoint
+ * supplier. The CDN API should never be instantiated directly, but rather accessed through the
  * {@link CloudFilesApi#cdnApiInRegion(String)} API.
  * <p/>
  * <h3>NOTE</h3>
  * The Cloud Files Service Type will always default to OpenStack Object Storage ("object-storage").
  * <p/>
- * 
- * 
+ *
+ *
  * @see CloudFilesApi#cdnApiInRegion(String)
  * @see CDNApi
  * @see RegionToEndpoint
@@ -53,7 +53,7 @@ import com.google.common.base.Supplier;
  *      Service Access Endpoints</a>
  */
 @Singleton
-public class RegionToCDNEndpoint implements Function<Object, URI> { 
+public class RegionToCDNEndpoint implements Function<Object, URI> {
 
    private final Supplier<Map<String, Supplier<URI>>> endpointsSupplier;
 
@@ -65,7 +65,7 @@ public class RegionToCDNEndpoint implements Function<Object, URI> {
    public URI apply(@Nullable Object from) {
       checkArgument(from != null && from instanceof String, "you must specify a region, as a String argument");
       Map<String, Supplier<URI>> regionToEndpoint = endpointsSupplier.get();
-      checkState(regionToEndpoint.size() > 0, "no region name to endpoint mappings configured!");
+      checkState(!regionToEndpoint.isEmpty(), "no region name to endpoint mappings configured!");
       checkArgument(regionToEndpoint.containsKey(from),
             "requested location %s, which is not in the configured locations: %s", from, regionToEndpoint);
       return regionToEndpoint.get(from).get();