Support stop and restart with Undertow

[wilkinsona]

2023-04-27 14:55:27.917 ERROR ${sys:PID} --- [  XNIO-2 task-2] i.u.request                              : UT005023: Exception handling request to /hello

jakarta.servlet.ServletException: UT010051: Deployment spring-boot has stopped
	at io.undertow.servlet.core.ManagedServlet.getServlet(ManagedServlet.java:185) ~[undertow-servlet-2.3.5.Final.jar:2.3.5.Final]
	at io.undertow.servlet.handlers.ServletHandler.handleRequest(ServletHandler.java:73) ~[undertow-servlet-2.3.5.Final.jar:2.3.5.Final]
	at io.undertow.servlet.handlers.security.ServletSecurityRoleHandler.handleRequest(ServletSecurityRoleHandler.java:62) ~[undertow-servlet-2.3.5.Final.jar:2.3.5.Final]
	at io.undertow.servlet.handlers.ServletChain$1.handleRequest(ServletChain.java:68) ~[undertow-servlet-2.3.5.Final.jar:2.3.5.Final]
	at io.undertow.servlet.handlers.ServletDispatchingHandler.handleRequest(ServletDispatchingHandler.java:36) ~[undertow-servlet-2.3.5.Final.jar:2.3.5.Final]
	at io.undertow.servlet.handlers.RedirectDirHandler.handleRequest(RedirectDirHandler.java:68) ~[undertow-servlet-2.3.5.Final.jar:2.3.5.Final]
	at io.undertow.servlet.handlers.security.SSLInformationAssociationHandler.handleRequest(SSLInformationAssociationHandler.java:117) ~[undertow-servlet-2.3.5.Final.jar:2.3.5.Final]
	at io.undertow.servlet.handlers.security.ServletAuthenticationCallHandler.handleRequest(ServletAuthenticationCallHandler.java:57) ~[undertow-servlet-2.3.5.Final.jar:2.3.5.Final]
	at io.undertow.server.handlers.PredicateHandler.handleRequest(PredicateHandler.java:43) ~[undertow-core-2.3.5.Final.jar:2.3.5.Final]
	at io.undertow.security.handlers.AbstractConfidentialityHandler.handleRequest(AbstractConfidentialityHandler.java:46) ~[undertow-core-2.3.5.Final.jar:2.3.5.Final]
	at io.undertow.servlet.handlers.security.ServletConfidentialityConstraintHandler.handleRequest(ServletConfidentialityConstraintHandler.java:64) ~[undertow-servlet-2.3.5.Final.jar:2.3.5.Final]
	at io.undertow.security.handlers.AuthenticationMechanismsHandler.handleRequest(AuthenticationMechanismsHandler.java:60) ~[undertow-core-2.3.5.Final.jar:2.3.5.Final]
	at io.undertow.servlet.handlers.security.CachedAuthenticatedSessionHandler.handleRequest(CachedAuthenticatedSessionHandler.java:77) ~[undertow-servlet-2.3.5.Final.jar:2.3.5.Final]
	at io.undertow.security.handlers.AbstractSecurityContextAssociationHandler.handleRequest(AbstractSecurityContextAssociationHandler.java:43) ~[undertow-core-2.3.5.Final.jar:2.3.5.Final]
	at io.undertow.server.handlers.PredicateHandler.handleRequest(PredicateHandler.java:43) ~[undertow-core-2.3.5.Final.jar:2.3.5.Final]
	at io.undertow.servlet.handlers.SendErrorPageHandler.handleRequest(SendErrorPageHandler.java:52) ~[undertow-servlet-2.3.5.Final.jar:2.3.5.Final]
	at io.undertow.server.handlers.PredicateHandler.handleRequest(PredicateHandler.java:43) ~[undertow-core-2.3.5.Final.jar:2.3.5.Final]
	at io.undertow.servlet.handlers.ServletInitialHandler.handleFirstRequest(ServletInitialHandler.java:276) [undertow-servlet-2.3.5.Final.jar:2.3.5.Final]
	at io.undertow.servlet.handlers.ServletInitialHandler$2.call(ServletInitialHandler.java:135) [undertow-servlet-2.3.5.Final.jar:2.3.5.Final]
	at io.undertow.servlet.handlers.ServletInitialHandler$2.call(ServletInitialHandler.java:132) [undertow-servlet-2.3.5.Final.jar:2.3.5.Final]
	at io.undertow.servlet.core.ServletRequestContextThreadSetupAction$1.call(ServletRequestContextThreadSetupAction.java:48) [undertow-servlet-2.3.5.Final.jar:2.3.5.Final]
	at io.undertow.servlet.core.ContextClassLoaderSetupAction$1.call(ContextClassLoaderSetupAction.java:43) [undertow-servlet-2.3.5.Final.jar:2.3.5.Final]
	at io.undertow.servlet.handlers.ServletInitialHandler.dispatchRequest(ServletInitialHandler.java:256) [undertow-servlet-2.3.5.Final.jar:2.3.5.Final]
	at io.undertow.servlet.handlers.ServletInitialHandler$1.handleRequest(ServletInitialHandler.java:101) [undertow-servlet-2.3.5.Final.jar:2.3.5.Final]
	at io.undertow.server.Connectors.executeRootHandler(Connectors.java:393) [undertow-core-2.3.5.Final.jar:2.3.5.Final]
	at io.undertow.server.HttpServerExchange$1.run(HttpServerExchange.java:859) [undertow-core-2.3.5.Final.jar:2.3.5.Final]
	at org.jboss.threads.ContextHandler$1.runWith(ContextHandler.java:18) [jboss-threads-3.5.0.Final.jar:3.5.0.Final]
	at org.jboss.threads.EnhancedQueueExecutor$Task.run(EnhancedQueueExecutor.java:2513) [jboss-threads-3.5.0.Final.jar:3.5.0.Final]
	at org.jboss.threads.EnhancedQueueExecutor$ThreadBody.run(EnhancedQueueExecutor.java:1512) [jboss-threads-3.5.0.Final.jar:3.5.0.Final]
	at org.xnio.XnioWorker$WorkerThreadFactory$1$1.run(XnioWorker.java:1282) [xnio-api-3.8.8.Final.jar:3.8.8.Final]
	at java.lang.Thread.run(Thread.java:833) [?:?]

[wilkinsona]

As far as I can tell, the way the central Undertow class works prevents us from supporting stop and restart.