JAVA-2082: Avoid race condition during cluster close and schema refre…

…sh (#1174)
apache · Feb 21, 2019 · 3cb45e8 · 3cb45e8
1 parent 5c98360
commit 3cb45e8
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Showing 3 changed files with 23 additions and 3 deletions.
diff --git a/changelog/README.md b/changelog/README.md
@@ -17,6 +17,7 @@
 - [documentation] JAVA-1964: Complete remaining "Coming Soon" sections in docs.
 - [improvement] JAVA-1950: Log server side warnings returned from a query.
 - [improvement] JAVA-2123: Allow to use QueryBuilder for building queries against Materialized Views.
+- [bug] JAVA-2082: Avoid race condition during cluster close and schema refresh.
 
 
 ### 3.6.0

diff --git a/driver-core/src/main/java/com/datastax/driver/core/EventDebouncer.java b/driver-core/src/main/java/com/datastax/driver/core/EventDebouncer.java
@@ -117,6 +117,12 @@ void stop() {
         break;
       }
     }
+    while (true) {
+      DeliveryAttempt previous = cancelImmediateDelivery();
+      if (immediateDelivery.compareAndSet(previous, null)) {
+        break;
+      }
+    }
 
     completeAllPendingFutures();
 
@@ -205,14 +211,21 @@ private void scheduleDelayedDelivery() {
   }
 
   private DeliveryAttempt cancelDelayedDelivery() {
-    DeliveryAttempt previous = delayedDelivery.get();
+    return cancelDelivery(delayedDelivery.get());
+  }
+
+  private DeliveryAttempt cancelImmediateDelivery() {
+    return cancelDelivery(immediateDelivery.get());
+  }
+
+  private DeliveryAttempt cancelDelivery(DeliveryAttempt previous) {
     if (previous != null) {
       previous.cancel();
     }
     return previous;
   }
 
-  void deliverEvents() {
+  private void deliverEvents() {
     if (state == State.STOPPED) {
       completeAllPendingFutures();
       return;

diff --git a/driver-core/src/main/java/com/datastax/driver/core/SchemaParser.java b/driver-core/src/main/java/com/datastax/driver/core/SchemaParser.java
@@ -93,7 +93,13 @@ void refresh(
             connection,
             cassandraVersion);
 
-    Metadata metadata = cluster.getMetadata();
+    Metadata metadata;
+    try {
+      metadata = cluster.getMetadata();
+    } catch (IllegalStateException e) {
+      logger.warn("Unable to refresh metadata, cluster has been closed");
+      return;
+    }
     metadata.lock.lock();
     try {
       if (targetType == null || targetType == KEYSPACE) {