I create a jetty server and want to programmatically and dynamically add servlets.
I setup logging and a console then proceed to create the server as follows:
Connector httpConn = null;
Connector httpsConn = null;
HandlerCollection handlers = new HandlerCollection();
httpConn = new SelectChannelConnector();
httpConn.setPort( httpPort );
httpConn.setName( "HTTPConnector" ); // simillar setup for httpsConn if needed
contextHandlers = new ContextHandlerCollection();
if( launchServlets ) {
// this is more or less the same servlet creation code as below but for launching
// static servlets (in this example, there are none)
holders = initializeServlets( configFilePath );
}
handlers.addHandler( contextHandlers );
server = new Server();
if( httpConn != null ) {
server.addConnector( httpConn );
}
if( httpsConn != null ) {
server.addConnector( httpsConn );
}
server.setGracefulShutdown( 1000 ); /
server.setStopAtShutdown( true );
server.setHandler( handlers );
server.start();
if( launchServlets ) {
// Catch any exception that occurs during servlet init()
// (must be called after server.start() )
for( int i = 0; i < holders.length; i++ ) {
if( holders[ i ] != null ) {
Exception initEx = holders[ i ].getUnavailableException();
if( initEx != null ) {
server.stop();
throw initEx;
}
}
}
}
So when I need to start a servlet, I do the following:
boolean isSecureOnly = false; // function that decides suppressed for now
String[] connectors;
MyServlet myServlet = new MyServlet();
ServletHolder holder = new ServletHolder( myServlet );
holder.setInitParameter( Constants.CONF_INIT_STRING_PARAM, configString );
holder.setInitParameter( Constants.CONF_INIT_NAME_PARAM, myName );
ServletContextHandler handler = new ServletContextHandler();
if( details != null ) {
details.sch = handler;
}
String contextPath = MyConfig.getContextPath( myProps, myName );
handler.setContextPath( contextPath );
handler.setAllowNullPathInfo( true );
// bind the servlet to the connectors it should be listening to
if( isSsl ) {
if( isSecureOnly ) {
connectors = new String[ 1 ];
connectors[0] = Constants.CONF_HTTPS_CONNECTOR;
} else {
connectors = new String[ 2 ];
connectors[0] = Constants.CONF_HTTPS_CONNECTOR;
connectors[1] = Constants.CONF_HTTP_CONNECTOR;
}
} else {
if( isSecureOnly ) {
throw new ConfigException( 50051 );
}
connectors = new String[ 1 ];
connectors[0] = Constants.CONF_HTTP_CONNECTOR;
}
handler.setConnectorNames( connectors );
if( myName != null ) {
handler.setDisplayName( MyMessage.message( 10025, myName ) );
} else {
handler.setDisplayName( MyMessage.message( 10001 ) );
}
handler.addServlet( holder, "/*" );
contextHandlers.addHandler( handler );
contextHandlers.mapContexts();
Exception initEx = holder.getUnavailableException();
if( initEx != null ) {
// deal with error
}
Although my dynamic servlet launching code appears to work without error, the console does not show the servlet initializing. When I have launchServlets=true, the code will statically launch the servlets and all is well but I want to launch them dynamically.
Do I have to manually make the servlet initialize (I thought servlets were isolated into their own memory space)? How do I tell Jetty to start the new Servlet?
Update: So far the only way I have managed to get the servlet to start is by server.stop()/server.join()/server.start(). I would like adding servlets (and removing - but that's a bonus question) not to interrupt service to existing servlets)?
I'm using jetty-all-server-8.1.3 and servlet api 3.0
Thanks in advance for your help/hints!
I'm not sure if it is the safe way to do it but I have gotten the serlvlet to start by calling start() on the ServletContextHandler() instead of stopping and starting the server.
This worked for both 8.1.3 and 9.2.4 (which I upgraded to along with upgrading to 3.1 of the servlet api)
Hopefully this will help someone else who is interested in doing something similar.