--- a/test/jdk/java/net/httpclient/http2/server/Queue.java	Fri Dec 01 19:25:34 2017 +0000
+++ b/test/jdk/java/net/httpclient/http2/server/Queue.java	Sat Dec 02 17:40:57 2017 +0000
@@ -25,6 +25,7 @@
 
 import java.io.IOException;
 import java.util.LinkedList;
+import java.util.Objects;
 import java.util.stream.Stream;
 
 // Each stream has one of these for input. Each Http2Connection has one
@@ -40,7 +41,7 @@
     private final T closeSentinel;
 
     Queue(T closeSentinel) {
-        this.closeSentinel = closeSentinel;
+        this.closeSentinel = Objects.requireNonNull(closeSentinel);
     }
 
     public synchronized int size() {
@@ -48,6 +49,7 @@
     }
 
     public synchronized void put(T obj) throws IOException {
+        Objects.requireNonNull(obj);
         if (closed || closing) {
             throw new IOException("stream closed");
         }