Handling obsoleteVersionException separately in JMX; no longer re-thr…

…owing obsoleteVersionException.

src/java/voldemort/store/stats/StatTrackingStore.java

@@ -24,6 +24,7 @@
 import voldemort.annotations.jmx.JmxOperation;
 import voldemort.store.DelegatingStore;
 import voldemort.store.Store;
+import voldemort.versioning.ObsoleteVersionException;
 import voldemort.versioning.Version;
 import voldemort.versioning.Versioned;
 
@@ -87,6 +88,9 @@ public void put(K key, Versioned<V> value) throws VoldemortException {
         long start = System.nanoTime();
         try {
             super.put(key, value);
+        } catch (ObsoleteVersionException e) {
+            // Don't rethrow this, as not to log it. Merely track it in JMX
+            stats.recordTime(Tracked.OBSOLETE, System.nanoTime() - start);
         } catch(VoldemortException e) {
             stats.recordTime(Tracked.EXCEPTION, System.nanoTime() - start);
             throw e;
@@ -159,6 +163,12 @@ public float getDeleteThroughput() {
         return stats.getThroughput(Tracked.DELETE);
     }
 
+    @JmxGetter(name = "numberOfObsoleteVersions",
+            description = "Number of ObsoleteVersionExceptions since the last reset.")
+    public long getNumberOfObsoleteVersions() {
+        return stats.getCount(Tracked.OBSOLETE);
+    }
+
     @JmxGetter(name = "numberOfExceptions", description = "The number of exceptions since the last reset.")
     public long getNumberOfExceptions() {
         return stats.getCount(Tracked.EXCEPTION);

src/java/voldemort/store/stats/Tracked.java

@@ -5,7 +5,8 @@ public enum Tracked {
     GET_ALL("getAll"),
     PUT("put"),
     DELETE("delete"),
-    EXCEPTION("exception");
+    EXCEPTION("exception"),
+    OBSOLETE("obsolete");
 
     private final String name;