tiny clean up

Author: cowtowncoder

src/main/java/com/fasterxml/uuid/impl/TimeBasedEpochGenerator.java

@@ -1,6 +1,7 @@
 package com.fasterxml.uuid.impl;
 
 import java.security.SecureRandom;
+import java.util.Objects;
 import java.util.Random;
 import java.util.UUID;
 import java.util.function.Consumer;
@@ -90,7 +91,7 @@ public TimeBasedEpochGenerator(Random rnd, UUIDClock clock)
      */
     protected TimeBasedEpochGenerator(Consumer<byte[]> randomNextBytes, UUIDClock clock)
     {
-        _randomNextBytes = randomNextBytes;
+        _randomNextBytes = Objects.requireNonNull(randomNextBytes);
         _clock = clock;
     }
 

src/test/java/com/fasterxml/uuid/UUIDComparatorTest.java

@@ -22,7 +22,6 @@
 
 import com.fasterxml.uuid.impl.TimeBasedEpochGenerator;
 
-import com.fasterxml.uuid.impl.TimeBasedEpochRandomGenerator;
 import junit.framework.TestCase;
 
 public class UUIDComparatorTest

src/test/java/com/fasterxml/uuid/impl/TimeBasedEpochGeneratorTest.java

@@ -6,6 +6,7 @@
 import java.util.function.Consumer;
 
 import com.fasterxml.uuid.UUIDClock;
+
 import junit.framework.TestCase;
 
 /**