[GitHub] [james-project] vttranlina commented on a change in pull request #911: JAMES-3724 - Implement LeakAware

[GitBox <gi...@apache.org>]

vttranlina commented on a change in pull request #911:
URL: https://github.com/apache/james-project/pull/911#discussion_r822487524



##########
File path: server/container/lifecycle-api/src/main/java/org/apache/james/lifecycle/api/Disposable.java
##########
@@ -29,4 +39,111 @@
      * Dispose the object
      */
     void dispose();
+
+    abstract class LeakAware implements Disposable {
+        public static class LeakDetectorException extends RuntimeException {
+            public LeakDetectorException() {
+                super();
+            }
+
+            public LeakDetectorException(String message) {
+                super(message);
+            }
+
+            public LeakDetectorException(String message, Throwable cause) {
+                super(message, cause);
+            }
+        }
+
+        public enum Level {
+            NONE,
+            SIMPLE,
+            ADVANCED,
+            TESTING;
+
+            static Level parse(String input) {
+                for (Level level : values()) {
+                    if (level.name().equalsIgnoreCase(input)) {
+                        return level;
+                    }
+                }
+                throw new IllegalArgumentException(String.format("Unknown level `%s`", input));
+            }
+        }
+
+        public static final ReferenceQueue<Object> REFERENCE_QUEUE = new ReferenceQueue<>();
+        public static final List<LeakAwareFinalizer> LEAK_REFERENCES = new ArrayList<>();
+        public static Level level;
+        private final AtomicBoolean isDisposed;
+
+        protected LeakAware() {
+            isDisposed = new AtomicBoolean(false);
+            level = Level.SIMPLE;    // todo
+            LEAK_REFERENCES.add(new LeakAwareFinalizer(this, REFERENCE_QUEUE));
+        }
+
+        public void disposed() {
+            isDisposed.set(true);
+        }
+
+        public static void track() {
+            if (leakDetectorEnabled()) {
+                Reference<?> referenceFromQueue;
+                while ((referenceFromQueue = REFERENCE_QUEUE.poll()) != null) {
+                    ((LeakAwareFinalizer) referenceFromQueue).detectLeak();
+                    referenceFromQueue.clear();
+                }
+            }
+        }
+
+        private static boolean leakDetectorEnabled() {
+            return level != Level.NONE;
+        }
+    }
+
+    class LeakAwareFinalizer extends PhantomReference<Object> {
+        private static final Logger LOGGER = LoggerFactory.getLogger(LeakAwareFinalizer.class);
+
+        private LeakAware referent;
+
+        public LeakAwareFinalizer(LeakAware referent, ReferenceQueue<? super Object> q) {
+            super(referent, q);
+//            this.referent = referent;

Review comment:
       I'm stuck here, 
   `referent` is used by `isNotDisposed` method.
   But if we set it, GC won't remove LeakAware from memory (REFERENCE_QUEUE always empty)
   




-- 
This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.

To unsubscribe, e-mail: notifications-unsubscribe@james.apache.org

For queries about this service, please contact Infrastructure at:
users@infra.apache.org



---------------------------------------------------------------------
To unsubscribe, e-mail: notifications-unsubscribe@james.apache.org
For additional commands, e-mail: notifications-help@james.apache.org