Multiple serlvet contexts being created instead of 1

[David Hemingway <dh...@datafast.net.au>]

Hi,

I still have the problem of not getting a singleton class to in fact be a singleton (its configured as a context listener inside web.xml). Some people suggested that perhaps i was getting more than 1 instance of the web app being created and that seems to be the case. My context si configured in my server.xml and the location of the webapp is not in tomcat's standard webapp directory. The follwoing 3 stack traces are basically a time line from when the server starts.

I threw some dummy, caught exceptions in my code so I could see the stack trace.

--------------------------
--> Server starts here <--
--------------------------

1st instance of the task scheduler listener (on server start as expected)

Context Initialized
The Servlet Context is org.apache.catalina.core.ApplicationContext@238a47
New Scheduler Created
java.lang.Exception: Testing
        at com.lawonline.Scheduler.getScheduler(Scheduler.java:43)
        at com.lawonline.StartServlet.contextInitialized(StartServlet.java:37)
        at org.apache.catalina.core.StandardContext.listenerStart(StandardContext.java:3269)
        at org.apache.catalina.core.StandardContext.start(StandardContext.java:3598)
        at org.apache.catalina.core.ContainerBase.start(ContainerBase.java:1188)
        at org.apache.catalina.core.StandardHost.start(StandardHost.java:738)
        at org.apache.catalina.core.ContainerBase.start(ContainerBase.java:1188)
        at org.apache.catalina.core.StandardEngine.start(StandardEngine.java:347)
        at org.apache.catalina.core.StandardService.start(StandardService.java:497)
        at org.apache.catalina.core.StandardServer.start(StandardServer.java:2189)
        at org.apache.catalina.startup.Catalina.start(Catalina.java:512)
        at org.apache.catalina.startup.Catalina.execute(Catalina.java:400)
        at org.apache.catalina.startup.Catalina.process(Catalina.java:180)
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
        at java.lang.reflect.Method.invoke(Method.java:324)
        at org.apache.catalina.startup.Bootstrap.main(Bootstrap.java:203)
        

----------------------------------------------------------------------
--> First request of a jsp (to any page  in the webapp) <--
----------------------------------------------------------------------

2nd instance (created from the warp connector)

Context Initialized
The Servlet Context is org.apache.catalina.core.ApplicationContext@11db6bb
New Scheduler Created
java.lang.Exception: Testing
        at com.lawonline.Scheduler.getScheduler(Scheduler.java:43)
        at com.lawonline.StartServlet.contextInitialized(StartServlet.java:37)
        at org.apache.catalina.core.StandardContext.listenerStart(StandardContext.java:3269)
        at org.apache.catalina.core.StandardContext.start(StandardContext.java:3598)
        at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:821)
        at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:807)
        at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:579)
        at org.apache.catalina.core.StandardHostDeployer.install(StandardHostDeployer.java:257)
        at org.apache.catalina.core.StandardHost.install(StandardHost.java:772)
        at org.apache.catalina.connector.warp.WarpConfigurationHandler.deploy(Unknown Source)
        at org.apache.catalina.connector.warp.WarpConfigurationHandler.handle(Unknown Source)
        at org.apache.catalina.connector.warp.WarpConnection.run(Unknown Source)
        at java.lang.Thread.run(Thread.java:536)
The listener is: com.lawonline.StartServlet@157ea4a


3rd (also created from the warp connector)

Context Initialized
The Servlet Context is org.apache.catalina.core.ApplicationContext@1568fb5
New Scheduler Created
java.lang.Exception: Testing
        at com.lawonline.Scheduler.getScheduler(Scheduler.java:43)
        at com.lawonline.StartServlet.contextInitialized(StartServlet.java:37)
        at org.apache.catalina.core.StandardContext.listenerStart(StandardContext.java:3269)
        at org.apache.catalina.core.StandardContext.start(StandardContext.java:3598)
        at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:821)
        at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:807)
        at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:579)
        at org.apache.catalina.core.StandardHostDeployer.install(StandardHostDeployer.java:257)
        at org.apache.catalina.core.StandardHost.install(StandardHost.java:772)
        at org.apache.catalina.connector.warp.WarpConfigurationHandler.deploy(Unknown Source)
        at org.apache.catalina.connector.warp.WarpConfigurationHandler.handle(Unknown Source)
        at org.apache.catalina.connector.warp.WarpConnection.run(Unknown Source)
        at java.lang.Thread.run(Thread.java:536)
The listener is: com.lawonline.StartServlet@a4488
Got Scheduler Instance


Why would the warp connector create a new context after the server start already created one? Why on earth would it create 2? The old ones never die, there is 3 independent ServletContexts continually running from this point forth.

I assume that this problem must be in Apache's config or in the connectors somewhere (or possibly a bug?)... It must be resolved for my application to function correctly. Any ideas from anyone would be greatly appreciated. What are the main differences between WARP and AJP ? .... Thanks

regards,
Dave