Programmatically update certificates in tomcat 8 without server restart

Question

In order to update the certificate that I use for SSL for my server I have a code that does the import\export and validation that I need.

It works well, but In order for the changes to take effect I have to restart the tomcat.
I wish to avoid the restart, and update it without using external tools (keytool for example).
I looked up for some similar questions, and found a solution - restarting the 443 connector. I'm able to do so, and the connector is stopping and starting, but the certificate was not updated. Only server restart actually updates it.

Is there some connector initialisation procedure that I'm missing?
Some system cache or objects that I should clear?

This is the code that I use for restarting the connector:

MBeanServer mbeanServer = null;
ObjectName objectName = null;
final ObjectName objectNameQuery = new ObjectName("*:type=Connector,port=443,*");
for (final MBeanServer server : (ArrayList<MBeanServer>) MBeanServerFactory.findMBeanServer(null)) {
    if (server.queryNames(objectNameQuery, null).size() > 0) {
        mbeanServer = server;
        objectName = (ObjectName) server.queryNames(objectNameQuery,null).toArray()[0];
        break;
    }
}

mbeanServer.invoke(objectName, "stop", null, null);
Thread.sleep(1000);
mbeanServer.invoke(objectName, "start", null, null);  

I see in the tomcat logs the following traces of the connector restart:
23-Apr-2017 15:42:00.292 INFO [BG-Task RestartTomcatConnector] org.apache.coyote.AbstractProtocol.stop Stopping ProtocolHandler ["http-nio-443"]
23-Apr-2017 15:42:01.349 INFO [BG-Task RestartTomcatConnector] org.apache.coyote.AbstractProtocol.start Starting ProtocolHandler ["http-nio-443"]

Answer 1

The problem was solved, these are the components:

1. server.xml must include bindOnInit="false". This is the config I use

   <Connector protocol="org.apache.coyote.http11.Http11NioProtocol"
           port="443" SSLEnabled="true" maxThreads="150"
           acceptCount="2000" scheme="https" secure="true"
           ciphers="TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256, TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256, TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384, TLS_DHE_RSA_WITH_AES_128_GCM_SHA256, TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384, TLS_DHE_RSA_WITH_AES_128_CBC_SHA256, TLS_DHE_RSA_WITH_AES_256_CBC_SHA256, TLS_DHE_RSA_WITH_AES_256_CBC_SHA"
           keystoreFile="webapps/ServerKeyStore"
           keystorePass="***"
           clientAuth="false" sslProtocol="TLS"
           sslEnabledProtocols="TLSv1.1,TLSv1.2" compression="on"
           compressableMimeType="text/html,text/xml,application/xml,application/json,application/javascript,text/css,text/plain"
           server="Portal" useSendfile="false"
           compressionMinSize="1024" bindOnInit="false"
   />
   

2. The Java code for the connector restart:

   public class TomcatConnectorRestarter implements Callable<Boolean> {
   
       private final int waitSeconds = 3;
       private final static ReentrantLock rl = new ReentrantLock();
   
       @Override
       public Boolean call() throws Exception {
           restartConnector();
           return true;
       }
   
       protected void restartConnector() throws Exception {
           try {
               if (tryLock()){
                   mLogger.info("Acquired lock");
                   try {
                       HTTPSConnectorMBean httpsConnector = null;
                       MBeanServer mbeanServer = null;
                       ObjectName objectName = null;
                       final ObjectName objectNameQuery = new ObjectName("*:type=Connector,port=443,*");
   
                       for (final MBeanServer server : (ArrayList<MBeanServer>) MBeanServerFactory.findMBeanServer(null)) {
                           if (server.queryNames(objectNameQuery, null).size() > 0) {
                               mbeanServer = server;
                               objectName = (ObjectName) server.queryNames(objectNameQuery, null).toArray()[0];
                               httpsConnector = new HTTPSConnectorMBean(objectName, mbeanServer);
                               break;
                           }
                       }
   
                       if (Objects.nonNull(httpsConnector)) {
                           mLogger.info("Stopping connector");
                           httpsConnector.stop();
                           mLogger.info("Waiting "+waitSeconds+" seconds after "+"stop"+" ...");
                           Thread.sleep(waitSeconds*1000);
                           mLogger.info("Starting connector");
                           httpsConnector.start();
                       }
                       else {
                           mLogger.error("Could not find connector object");
                       }
                   }
                   catch (Exception e) {
                       mLogger.error("Failed restarting connector",e);
                   }
               }
               else {
                   mLogger.warn("Operation is in process");
               }
           }
           finally {
               unlock();
           }
       }
   
       private void unlock() {
           if (rl.isHeldByCurrentThread()) {
               mLogger.debug("Releasing lock");
               rl.unlock();
           }
       }
   
       private boolean tryLock() {
           return !rl.isHeldByCurrentThread() && rl.tryLock();
       }
   
       private enum MBeanConnectorAction {
           start,stop,getState;
       }
   
       private abstract class MBeansObjectAction {
           private final ObjectName on;
           private final MBeanServer server;
   
           public MBeansObjectAction(ObjectName on, MBeanServer server) {
               this.on = on;
               this.server = server;
           }
   
           protected Object invoke(MBeanConnectorAction cmd) throws InstanceNotFoundException, ReflectionException, MBeanException {
               return server.invoke(on, cmd.toString(), null, null);
           }
       }
   
       private class HTTPSConnectorMBean extends MBeansObjectAction {
   
           public HTTPSConnectorMBean(ObjectName on, MBeanServer server) {
               super(on, server);
           }
   
           public void start() throws InstanceNotFoundException, ReflectionException, MBeanException {
               invoke(MBeanConnectorAction.start);
           }
           public void stop() throws InstanceNotFoundException, ReflectionException, MBeanException {
               invoke(MBeanConnectorAction.stop);
           }
           public Object status() throws InstanceNotFoundException, ReflectionException, MBeanException {
               return invoke(MBeanConnectorAction.getState);
           }
       }
   }