Github user revans2 commented on a diff in the pull request:
https://github.com/apache/storm/pull/2743#discussion_r198986069
--- Diff:
storm-server/src/main/java/org/apache/storm/metric/timed/TimerDecorated.java ---
@@ -0,0 +1,50 @@
+/**
+ * Licensed to the Apache Software Foundation (ASF) under one or more
contributor license agreements.
+ * See the NOTICE file distributed with this work for additional
information regarding copyright ownership.
+ * The ASF licenses this file to you under the Apache License, Version 2.0
(the "License");
+ * you may not use this file except in compliance with the License. You
may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an "AS IS"
BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
limitations under the License.
+ */
+
+package org.apache.storm.metric.timed;
+
+import com.codahale.metrics.Timer;
+
+import java.util.concurrent.atomic.AtomicReference;
+
+public interface TimerDecorated extends AutoCloseable {
+ public boolean hasStopped();
+
+ default boolean hasStopped(final AtomicReference<Timer.Context>
timing) {
+ return timing.get() == null;
+ }
+
+ public long stopTiming();
+
+ /**
+ * Stop the timer for measured object. Should be executed only once.
+ *
+ * @return Time a object is in use, or under measurement, in
nanoseconds.
+ * @throws NullPointerException this method is called more than once.
+ */
+ default long stopTiming(final AtomicReference<Timer.Context>
timingRef) throws NullPointerException {
+ Timer.Context timing = timingRef.get();
+ if (timing != null) {
+ long lapses = timing.stop();
+ timingRef.set(null);
+ return lapses;
+ }
+ throw new NullPointerException("Timer for this object has stopped
and cleared");
--- End diff --
So the return value, `lapses`, is never used anywhere, and I don't see a
lot of value in throwing an NPE for doing a double close of a resource. I
would prefer to have it have an assertion so that when the code is under test
we validate that we are not doing a double free, but not really worry about it
in production, because it has already been closed.
---
