Lock async for setAutoCommit

Author: Michael-A-McMahon

src/main/java/oracle/r2dbc/impl/OracleConnectionImpl.java

@@ -569,9 +569,7 @@ public Publisher<Void> rollbackTransactionToSavepoint(String name) {
   @Override
   public Publisher<Void> setAutoCommit(boolean autoCommit) {
     requireOpenConnection(jdbcConnection);
-    // TODO: Replace defer with AsyncLock.get(...). It will defer execution
-    //  until a subscriber subscribes.
-    return Mono.defer(() -> fromJdbc(() -> {
+    return Mono.from(adapter.getLock().flatMap(() -> {
       if (autoCommit == jdbcConnection.getAutoCommit()) {
         return Mono.empty(); // No change
       }
@@ -585,7 +583,7 @@ else if (! autoCommit) {
         // Changing auto-commit from disabled to enabled. Commit in case
         // there is an active transaction.
         return Mono.from(commitTransaction())
-          .doOnSuccess(nil -> runJdbc(() ->
+          .concatWith(adapter.getLock().run(() ->
             jdbcConnection.setAutoCommit(true)));
       }
     }))