workaround for shutdownNow leak in java21

Author: myronkscott

common/src/main/java/com/tc/net/protocol/tcm/MessageMonitorImpl.java

@@ -93,6 +93,7 @@ private ScheduledFuture<?> startLogging(final Logger logger, int intervalSeconds
   public void shutdown() {
     currentTask.cancel(true);
     timer.shutdownNow();
+    timer.shutdown();
   }
 
   @Override

tc-client/src/main/java/com/tc/object/ClientEntityManagerImpl.java

@@ -402,6 +402,7 @@ public void shutdown() {
       }
     }
     this.endpointCloser.shutdownNow(); // ignore the return.  nothing we can do
+    this.endpointCloser.shutdown();
     // And then drop them.
     if (logger.isDebugEnabled()) {
       MapListPrettyPrint print = new MapListPrettyPrint();

tc-server/src/main/java/com/tc/objectserver/entity/ActiveToPassiveReplication.java

@@ -386,6 +386,7 @@ public void nodeLeft(NodeID nodeID) {
 
   public void close() {
     passiveSyncPool.shutdownNow();
+    passiveSyncPool.shutdown();  // bug in java21 under certain class loading scenarios
     while (!waiters.isEmpty()) {
       LOGGER.info("waiters not empty on shutdown.  Removing:" + passiveNodes);
       Iterator<Map.Entry<SyncReplicationActivity.ActivityID, ActivePassiveAckWaiter>> items = waiters.entrySet().iterator();