Merge branch 'master' into javawebsocket-jsr

jetty-websocket/websocket-common/src/main/java/org/eclipse/jetty/websocket/common/extensions/ExtensionStack.java

@@ -250,19 +250,35 @@ public class ExtensionStack extends ContainerLifeCycle implements IncomingFrames
     {
         StringBuilder s = new StringBuilder();
         s.append("ExtensionStack[");
-        s.append("extensions=[");
+        s.append("extensions=");
-        boolean delim = false;
+        if (extensions == null)
-        for (Extension ext : extensions)
         {
-            if (delim)
+            s.append("<null>");
-            {
-                s.append(',');
-            }
-            s.append(ext.getName());
-            delim = true;
         }
-        s.append("],incoming=").append(this.nextIncoming.getClass().getName());
+        else
-        s.append(",outgoing=").append(this.nextOutgoing.getClass().getName());
+        {
+            s.append('[');
+            boolean delim = false;
+            for (Extension ext : extensions)
+            {
+                if (delim)
+                {
+                    s.append(',');
+                }
+                if (ext == null)
+                {
+                    s.append("<null>");
+                }
+                else
+                {
+                    s.append(ext.getName());
+                }
+                delim = true;
+            }
+            s.append(']');
+        }
+        s.append(",incoming=").append((this.nextIncoming == null)?"<null>":this.nextIncoming.getClass().getName());
+        s.append(",outgoing=").append((this.nextOutgoing == null)?"<null>":this.nextOutgoing.getClass().getName());
         s.append("]");
         return s.toString();
     }

jetty-websocket/websocket-common/src/test/java/org/eclipse/jetty/websocket/common/extensions/ExtensionStackTest.java

@@ -160,4 +160,12 @@ public class ExtensionStackTest
             stack.stop();
         }
     }
+
+    @Test
+    public void testToString()
+    {
+        ExtensionStack stack = createExtensionStack();
+        // Shouldn't cause a NPE.
+        LOG.debug("Shouldn't cause a NPE: {}",stack.toString());
+    }
 }