moved to Queue rather than Deque

Author: dghgit

prov/src/main/java/org/bouncycastle/jcajce/provider/drbg/DRBG.java

@@ -9,14 +9,13 @@
 import java.security.SecureRandom;
 import java.security.SecureRandomSpi;
 import java.security.Security;
-import java.util.concurrent.ConcurrentLinkedDeque;
+import java.util.concurrent.ConcurrentLinkedQueue;
 import java.util.concurrent.atomic.AtomicBoolean;
 import java.util.concurrent.atomic.AtomicInteger;
 import java.util.concurrent.atomic.AtomicReference;
 import java.util.logging.Level;
 import java.util.logging.Logger;
 
-import org.bouncycastle.crypto.CryptoServicesRegistrar;
 import org.bouncycastle.crypto.digests.SHA512Digest;
 import org.bouncycastle.crypto.macs.HMac;
 import org.bouncycastle.crypto.prng.EntropySource;
@@ -33,7 +32,8 @@
 
 /**
  * <b>DRBG Configuration</b><br/>
- * <p>org.bouncycastle.drbg.gather_pause_secs - is to stop the entropy collection thread from grabbing all
+ * <p>
+ * org.bouncycastle.drbg.gather_pause_secs - is to stop the entropy collection thread from grabbing all
  * available entropy on the system. The original motivation for the hybrid infrastructure was virtual machines
  * sometimes produce very few bits of entropy a second, the original approach (which "worked" at least for BC) was
  * to just read on the second thread and allow things to progress around it, but it did tend to hog the system
@@ -42,9 +42,11 @@
  * enough to allow everyone to work together, but small enough to ensure the provider's DRBG is being regularly
  * reseeded.
  * </p>
- * <p>org.bouncycastle.drbg.entropysource - is the class name for an implementation of EntropySourceProvider.
+ * <p>
+ * org.bouncycastle.drbg.entropysource - is the class name for an implementation of EntropySourceProvider.
  * For example, one could be provided which just reads directly from /dev/random and the extra infrastructure used here
- * could be avoided.</p>
+ * could be avoided.
+ * </p>
  */
 public class DRBG
 {
@@ -301,7 +303,7 @@ private static byte[] generateNonceIVPersonalizationString(byte[] seed)
     private static class EntropyDaemon
         implements Runnable
     {
-        private final ConcurrentLinkedDeque<Runnable> tasks = new ConcurrentLinkedDeque<Runnable>();
+        private final ConcurrentLinkedQueue<Runnable> tasks = new ConcurrentLinkedQueue<Runnable>();
 
         void addTask(Runnable task)
         {
@@ -313,7 +315,7 @@ public void run()
         {
             while (!Thread.currentThread().isInterrupted())
             {
-                Runnable task = tasks.pollFirst();
+                Runnable task = tasks.poll();
 
                 if (task != null)
                 {