fix: checks pool maintainer is not closed on close

Verifies that the pool maintainer is not closed before closing it. Also moves the check of pendingClosures into the synchronized block to make sure no stale reads are made.
googleapis · Jan 14, 2021 · 04ffcf5 · 04ffcf5
1 parent 1363543
commit 04ffcf5
Showing 1 changed file with 10 additions and 8 deletions.
diff --git a/google-cloud-spanner/src/main/java/com/google/cloud/spanner/SessionPool.java b/google-cloud-spanner/src/main/java/com/google/cloud/spanner/SessionPool.java
@@ -1617,10 +1617,12 @@ public void run() {
 
     void close() {
       synchronized (lock) {
-        closed = true;
-        scheduledFuture.cancel(false);
-        if (!running) {
-          decrementPendingClosures(1);
+        if (!closed) {
+          closed = true;
+          scheduledFuture.cancel(false);
+          if (!running) {
+            decrementPendingClosures(1);
+          }
         }
       }
     }
@@ -2188,11 +2190,11 @@ ListenableFuture<Void> closeAsync(ClosedException closedException) {
           closeSessionAsync(session);
         }
       }
-    }
 
-    // Nothing to be closed, mark as complete
-    if (pendingClosure == 0) {
-      closureFuture.set(null);
+      // Nothing to be closed, mark as complete
+      if (pendingClosure == 0) {
+        closureFuture.set(null);
+      }
     }
 
     retFuture.addListener(