Optimization. JM-476

git-svn-id: http://svn.igniterealtime.org/svn/repos/messenger/trunk@3142 b35dd754-fafc-0310-a699-88a17e54d16e

src/java/org/jivesoftware/messenger/interceptor/InterceptorManager.java

@@ -214,21 +214,25 @@ public class InterceptorManager {
             throws PacketRejectedException
     {
         // Invoke the global interceptors for this packet
-        for (PacketInterceptor interceptor : globalInterceptors) {
-            try {
-                interceptor.interceptPacket(packet, session, read, processed);
-            }
-            catch (PacketRejectedException e) {
-                if (processed) {
-                    Log.error("Post interceptor cannot reject packet.", e);
+        // Checking if collection is empty to prevent creating an iterator of
+        // a CopyOnWriteArrayList that is an expensive operation
+        if (!globalInterceptors.isEmpty()) {
+            for (PacketInterceptor interceptor : globalInterceptors) {
+                try {
+                    interceptor.interceptPacket(packet, session, read, processed);
                 }
-                else {
-                    // Throw this exception since we don't really want to catch it
-                    throw e;
+                catch (PacketRejectedException e) {
+                    if (processed) {
+                        Log.error("Post interceptor cannot reject packet.", e);
+                    }
+                    else {
+                        // Throw this exception since we don't really want to catch it
+                        throw e;
+                    }
+                }
+                catch (Exception e) {
+                    Log.error("Error in interceptor", e);
                 }
-            }
-            catch (Exception e) {
-                Log.error("Error in interceptor", e);
             }
         }
         // Invoke the interceptors that are related to the address of the session