Preserve commit notifications when shutdown rejects submission

ebean-core/src/main/java/io/ebeaninternal/server/transaction/TransactionManager.java

@@ -40,6 +40,7 @@
 import java.util.List;
 import java.util.Set;
 import java.util.concurrent.ConcurrentHashMap;
+import java.util.concurrent.RejectedExecutionException;
 
 import static java.lang.System.Logger.Level.DEBUG;
 import static java.lang.System.Logger.Level.ERROR;
@@ -336,7 +337,13 @@ public final void notifyOfCommit(SpiTransaction transaction) {
     try {
       PostCommitProcessing postCommit = new PostCommitProcessing(clusterManager, this, transaction);
       postCommit.notifyLocalCache();
-      backgroundExecutor.execute(postCommit.backgroundNotify());
+      Runnable backgroundNotify = postCommit.backgroundNotify();
+      try {
+        backgroundExecutor.execute(backgroundNotify);
+      } catch (RejectedExecutionException ex) {
+        // Preserve notifications when shutdown has stopped the background executor.
+        backgroundNotify.run();
+      }
     } catch (Exception ex) {
       log.log(ERROR, "NotifyOfCommit failed. L2 Cache potentially not notified.", ex);
     }

ebean-core/src/test/java/io/ebeaninternal/server/transaction/TransactionManagerNotifyOfCommitTest.java

@@ -0,0 +1,44 @@
+package io.ebeaninternal.server.transaction;
+
+import io.ebean.BackgroundExecutor;
+import io.ebean.cache.ServerCacheNotify;
+import io.ebean.config.DatabaseConfig;
+import io.ebean.config.dbplatform.DatabasePlatform;
+import io.ebean.plugin.SpiServer;
+import io.ebeaninternal.api.SpiLogManager;
+import io.ebeaninternal.api.SpiProfileHandler;
+import io.ebeaninternal.api.SpiTransaction;
+import io.ebeaninternal.api.TransactionEvent;
+import io.ebeaninternal.server.cluster.ClusterManager;
+import io.ebeaninternal.server.core.PersistRequestBean;
+import io.ebeaninternal.server.deploy.BeanDescriptorManager;
+import io.ebeanservice.docstore.api.DocStoreUpdateProcessor;
+import org.junit.jupiter.api.Test;
+
+import java.util.concurrent.RejectedExecutionException;
+
+import static org.mockito.Mockito.*;
+
+class TransactionManagerNotifyOfCommitTest {
+
+  @Test
+  void rejectedSubmission_notifiesListenerSynchronously() {
+    var executor = mock(BackgroundExecutor.class);
+    doThrow(new RejectedExecutionException()).when(executor).execute(any(Runnable.class));
+    var config = new DatabaseConfig();
+    config.setDatabasePlatform(new DatabasePlatform());
+    var manager = new TransactionManager(new TransactionManagerOptions(mock(SpiServer.class), true, config,
+      mock(TransactionScopeManager.class), mock(ClusterManager.class), executor,
+      mock(DocStoreUpdateProcessor.class), mock(BeanDescriptorManager.class), mock(DataSourceSupplier.class),
+      mock(SpiProfileHandler.class), mock(SpiLogManager.class), mock(TableModState.class), mock(ServerCacheNotify.class)));
+    var listener = mock(PersistRequestBean.class);
+    var event = new TransactionEvent();
+    event.addListenerNotify(listener);
+    var transaction = mock(SpiTransaction.class);
+    when(transaction.event()).thenReturn(event);
+
+    manager.notifyOfCommit(transaction);
+
+    verify(listener).notifyLocalPersistListener();
+  }
+}