Provides wait mechanism in test for Radius Server

Change-Id: If571458efb8a66ec972106dad34418b23d772fe9
diff --git a/app/src/test/java/org/opencord/aaa/impl/AaaStatisticsTest.java b/app/src/test/java/org/opencord/aaa/impl/AaaStatisticsTest.java
index c9564b0..25b8fc8 100644
--- a/app/src/test/java/org/opencord/aaa/impl/AaaStatisticsTest.java
+++ b/app/src/test/java/org/opencord/aaa/impl/AaaStatisticsTest.java
@@ -582,20 +582,32 @@
     }
 
     /*
-     * Mock implementation of SocketBasedRadiusCommunicator class.
-     *
-     */
+    * Mock implementation of SocketBasedRadiusCommunicator class.
+    *
+    */
     class TestSocketBasedRadiusCommunicator extends SocketBasedRadiusCommunicator {
 
         TestSocketBasedRadiusCommunicator(ApplicationId appId, PacketService pktService, AaaManager aaaManager) {
             super(appId, pktService, aaaManager);
         }
 
+        /**
+        * Wait 10 millis to simulate a non 0 rtt.
+        *
+        * @throws InterruptedException
+        */
+        private void waitPacket() throws InterruptedException {
+            synchronized (this) {
+                this.wait(10);
+            }
+        }
+
         // Implementation of socketBasedRadiusCommunicator--> run() method
         public void handlePacketFromServer(PacketContext context) {
-
             RADIUS incomingPkt = (RADIUS) fetchPacket(savedPackets.size() - 1);
             try {
+                // wait a couple of millis to avoid rtt being 0
+                waitPacket();
                 if (context == null) {
                     aaaStatisticsManager.handleRoundtripTime(incomingPkt.getIdentifier());
                     aaaManager.handleRadiusPacket(incomingPkt);
@@ -610,6 +622,8 @@
                 aaaManager.aaaStatisticsManager.getAaaStats().increaseMalformedResponsesRx();
                 aaaStatisticsManager.getAaaStats().countDroppedResponsesRx();
                 log.error("Cannot deserialize packet", dex);
+            } catch (InterruptedException inte) {
+                Thread.currentThread().interrupt();
             }
         }