Fix findbugs warnings

[controller.git] / opendaylight / md-sal / sal-clustering-commons / src / main / java / org / opendaylight / controller / cluster / common / actor / MessageTracker.java

diff --git a/opendaylight/md-sal/sal-clustering-commons/src/main/java/org/opendaylight/controller/cluster/common/actor/MessageTracker.java b/opendaylight/md-sal/sal-clustering-commons/src/main/java/org/opendaylight/controller/cluster/common/actor/MessageTracker.java
index 08516252fd601608f661f44293efe105de914033..65cef56a2bb9624a7b30d847b5932d1c79f82d14 100644 (file)
--- a/opendaylight/md-sal/sal-clustering-commons/src/main/java/org/opendaylight/controller/cluster/common/actor/MessageTracker.java
+++ b/opendaylight/md-sal/sal-clustering-commons/src/main/java/org/opendaylight/controller/cluster/common/actor/MessageTracker.java
@@ -10,6 +10,7 @@ package org.opendaylight.controller.cluster.common.actor;
 
 import static java.util.concurrent.TimeUnit.MILLISECONDS;
 import static java.util.concurrent.TimeUnit.NANOSECONDS;
+
 import com.google.common.annotations.Beta;
 import com.google.common.annotations.VisibleForTesting;
 import com.google.common.base.Optional;
@@ -28,7 +29,7 @@ import org.slf4j.LoggerFactory;
  * expected to arrive in a given time interval does not arrive. It attempts to keep track of all the messages that
  * received between the arrival of two instances of the same message and the amount of time it took to process each
  * of those messages.
- * <br/>
+ * <br>
  * Usage of the API is as follows,
  * <pre>
  *
@@ -41,34 +42,37 @@ import org.slf4j.LoggerFactory;
  *
  *     .....
  *
- *     MessageTracker.Context context = tracker.received(message);
- *
- *     if(context.error().isPresent()){
- *         LOG.error("{}", context.error().get());
- *     }
+ *     try (MessageTracker.Context context = tracker.received(message)) {
  *
- *     // Some custom processing
- *     process(message);
+ *         if (context.error().isPresent()){
+ *             LOG.error("{}", context.error().get());
+ *         }
  *
- *     context.done();
+ *         // Some custom processing
+ *         process(message);
+ *     }
  *
  * </pre>
  */
 @Beta
 @NotThreadSafe
 public final class MessageTracker {
-    public static abstract class Context {
+    public abstract static class Context implements AutoCloseable {
         Context() {
             // Hidden to prevent outside instantiation
         }
 
-        public abstract Context done();
         public abstract Optional<Error> error();
+
+        @Override
+        public abstract void close();
     }
 
     public interface Error {
         Object getLastExpectedMessage();
+
         Object getCurrentExpectedMessage();
+
         List<MessageProcessingTime> getMessageProcessingTimesSinceLastExpectedMessage();
     }
 
@@ -84,12 +88,11 @@ public final class MessageTracker {
 
         @Override
         public String toString() {
-            return "MessageProcessingTime{" +
-                    "messageClass=" + messageClass.getSimpleName() +
-                    ", elapsedTimeInMillis=" + NANOSECONDS.toMillis(elapsedTimeInNanos) +
-                    '}';
+            return "MessageProcessingTime [messageClass=" + messageClass + ", elapsedTimeInMillis="
+                   + NANOSECONDS.toMillis(elapsedTimeInNanos) + "]";
         }
 
+
         public Class<?> getMessageClass() {
             return messageClass;
         }
@@ -102,8 +105,8 @@ public final class MessageTracker {
     private static final Logger LOG = LoggerFactory.getLogger(MessageTracker.class);
     private static final Context NO_OP_CONTEXT = new Context() {
         @Override
-        public Context done() {
-            return this;
+        public void close() {
+            // No-op
         }
 
         @Override
@@ -138,9 +141,10 @@ public final class MessageTracker {
     }
 
     /**
+     * Constructs an instance.
      *
-     * @param expectedMessageClass The class of the message to track
-     * @param expectedArrivalIntervalInMillis The expected arrival interval between two instances of the expected
+     * @param expectedMessageClass the class of the message to track
+     * @param expectedArrivalIntervalInMillis the expected arrival interval between two instances of the expected
      *                                        message
      */
     public MessageTracker(final Class<?> expectedMessageClass, final long expectedArrivalIntervalInMillis) {
@@ -233,12 +237,12 @@ public final class MessageTracker {
 
     private abstract class AbstractTimedContext extends Context {
         abstract Object message();
+
         abstract Stopwatch stopTimer();
 
         @Override
-        public final Context done() {
+        public final void close() {
             processed(message(), stopTimer().elapsed(NANOSECONDS));
-            return this;
         }
     }
 
@@ -246,10 +250,10 @@ public final class MessageTracker {
         private final Stopwatch stopwatch = Stopwatch.createUnstarted(ticker);
         private Object message;
 
-        void reset(final Object message) {
-            this.message = Preconditions.checkNotNull(message);
+        void reset(final Object newMessage) {
+            this.message = Preconditions.checkNotNull(newMessage);
             Preconditions.checkState(!stopwatch.isRunning(),
-                "Trying to reset a context that is not done (%s). currentMessage = %s", this, message);
+                "Trying to reset a context that is not done (%s). currentMessage = %s", this, newMessage);
             stopwatch.start();
         }