Thread ID for servlets implementing SingleThreadModel

Container creates different instances for every request to a Servlet implementing SingleThreadModel. So I tried to print thread IDs for such a Servlet by calling Thread.currentThread().getId(). I expected different thread IDs for every request to this Servlet. But what I noticed is - the same thread ID is logged several times (I got thread id 98 and 99 more than once). Can someone please explain why this is behaving like that?

If container creates a thread pool and if it assigns different requests to same thread (fetched from the pool), then what's the point in creating multiple instances of one servlet?

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  • Thread pool for Servlets

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              Hi all,
              I am facing a big problem while doing a concurrent testing of my web application.
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  • Restricting Thread Pool for Servlet instances

    I am using WebLogic5.1.0 version wherein I am registering a Servlet which
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    Sandeep Rajpathak wrote:
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  • Implementing SingleThreadModel on a Servlet

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  • What is the "Count" property for Servlet in Console?

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  • Thread pool in servlet container

    Hello all,
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  • Thread waiting for monitor - appending to previous post

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              Tangosol, Inc.
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              "Geordie" <[email protected]> wrote in message
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    [#|2005-08-23T11:44:51.061+0100|INFO|sun-appserver-pe8.0.0_01|javax.enterprise.system.core.transaction|_ThreadID=10;|JTS5014: Recoverable JTS instance, serverId = [100]|#]
    [#|2005-08-23T11:44:53.917+0100|INFO|sun-appserver-pe8.0.0_01|javax.enterprise.system.core|_ThreadID=10;|Satisfying Optional Packages dependencies...|#]
    [#|2005-08-23T11:44:54.400+0100|INFO|sun-appserver-pe8.0.0_01|javax.enterprise.resource.resourceadapter|_ThreadID=10;|RAR7008 : Initialized monitoring registry and listeners|#]
    [#|2005-08-23T11:44:56.346+0100|INFO|sun-appserver-pe8.0.0_01|javax.enterprise.system.core|_ThreadID=10;|CORE5100:Loading system apps|#]
    [#|2005-08-23T11:44:58.494+0100|INFO|sun-appserver-pe8.0.0_01|javax.enterprise.system.container.ejb|_ThreadID=10;|EJB5109:EJB Timer Service started successfully for datasource [jdbc/__TimerPool]|#]
    [#|2005-08-23T11:44:58.494+0100|INFO|sun-appserver-pe8.0.0_01|javax.enterprise.system.core.classloading|_ThreadID=10;|LDR5010: All ejb(s) of [__ejb_container_timer_app] loaded successfully!|#]
    [#|2005-08-23T11:44:59.954+0100|INFO|sun-appserver-pe8.0.0_01|javax.enterprise.system.core.classloading|_ThreadID=10;|LDR5010: All ejb(s) of [MEjbApp] loaded successfully!|#]
    [#|2005-08-23T11:45:01.401+0100|INFO|sun-appserver-pe8.0.0_01|javax.enterprise.system.core.classloading|_ThreadID=10;|LDR5010: All ejb(s) of [ConverterApp] loaded successfully!|#]
    [#|2005-08-23T11:45:01.407+0100|INFO|sun-appserver-pe8.0.0_01|javax.enterprise.system.container.web|_ThreadID=10;|WEB0100: Loading web module [ConverterApp:war-ic.war] in virtual server [server] at [converter]|#]
    [#|2005-08-23T11:45:02.500+0100|INFO|sun-appserver-pe8.0.0_01|javax.enterprise.system.core.classloading|_ThreadID=10;|LDR5010: All ejb(s) of [travelApp] loaded successfully!|#]
    [#|2005-08-23T11:45:02.792+0100|INFO|sun-appserver-pe8.0.0_01|javax.enterprise.system.core.classloading|_ThreadID=10;|LDR5010: All ejb(s) of [HelloWorldApp] loaded successfully!|#]
    [#|2005-08-23T11:45:02.798+0100|INFO|sun-appserver-pe8.0.0_01|javax.enterprise.system.container.web|_ThreadID=10;|WEB0302: Starting Tomcat.|#]
    [#|2005-08-23T11:45:03.281+0100|INFO|sun-appserver-pe8.0.0_01|javax.enterprise.system.container.web|_ThreadID=10;|WEB0100: Loading web module [adminapp] in virtual server [server] at [web1]|#]
    [#|2005-08-23T11:45:03.335+0100|INFO|sun-appserver-pe8.0.0_01|javax.enterprise.system.container.web|_ThreadID=10;|WEB0100: Loading web module [admingui] in virtual server [server] at [asadmin]|#]
    [#|2005-08-23T11:45:03.338+0100|WARNING|sun-appserver-pe8.0.0_01|javax.enterprise.system.container.web|_ThreadID=10;|WEB0500: default-locale attribute of locale-charset-info element has been deprecated and is being ignored. Use default-charset attribute of parameter-encoding element instead|#]
    [#|2005-08-23T11:45:03.351+0100|INFO|sun-appserver-pe8.0.0_01|javax.enterprise.system.container.web|_ThreadID=10;|WEB0100: Loading web module [com_sun_web_ui] in virtual server [server] at [com_sun_web_ui]|#]
    [#|2005-08-23T11:45:03.371+0100|INFO|sun-appserver-pe8.0.0_01|javax.enterprise.system.container.web|_ThreadID=10;|WEB0100: Loading web module [jTravellerService] in virtual server [server] at [jTravellerService]|#]
    [#|2005-08-23T11:45:03.399+0100|INFO|sun-appserver-pe8.0.0_01|javax.enterprise.system.container.web|_ThreadID=10;|WEB0100: Loading web module [hello-jaxrpc] in virtual server [server] at [hello-jaxrpc]|#]
    [#|2005-08-23T11:45:03.427+0100|INFO|sun-appserver-pe8.0.0_01|org.apache.catalina.startup.Embedded|_ThreadID=10;|Starting tomcat server|#]
    [#|2005-08-23T11:45:03.428+0100|INFO|sun-appserver-pe8.0.0_01|org.apache.catalina.startup.Embedded|_ThreadID=10;|Catalina naming disabled|#]
    [#|2005-08-23T11:45:03.637+0100|INFO|sun-appserver-pe8.0.0_01|org.apache.catalina.core.StandardEngine|_ThreadID=10;|Starting Servlet Engine: Sun-Java-System/Application-Server-PE-8.0|#]
    [#|2005-08-23T11:45:13.214+0100|INFO|sun-appserver-pe8.0.0_01|javax.enterprise.resource.webservices.rpc.server.http|_ThreadID=10;|JAXRPC.JAXRPCSERVLET.12: JAX-RPC context listener initializing|#]
    [#|2005-08-23T11:45:14.087+0100|INFO|sun-appserver-pe8.0.0_01|javax.enterprise.resource.webservices.rpc.server.http|_ThreadID=10;|JAXRPC.JAXRPCSERVLET.14: JAX-RPC servlet initializing|#]
    [#|2005-08-23T11:45:14.268+0100|INFO|sun-appserver-pe8.0.0_01|org.apache.catalina.startup.ContextConfig|_ThreadID=10;|Missing application web.xml, using defaults only StandardEngine[server].StandardHost[server].StandardContext[]|#]
    [#|2005-08-23T11:45:18.600+0100|INFO|sun-appserver-pe8.0.0_01|javax.enterprise.resource.webservices.rpc.server.http|_ThreadID=10;|JAXRPC.JAXRPCSERVLET.12: JAX-RPC context listener initializing|#]
    [#|2005-08-23T11:45:18.657+0100|INFO|sun-appserver-pe8.0.0_01|javax.enterprise.resource.webservices.rpc.server.http|_ThreadID=10;|JAXRPC.JAXRPCSERVLET.14: JAX-RPC servlet initializing|#]
    [#|2005-08-23T11:45:20.710+0100|INFO|sun-appserver-pe8.0.0_01|org.apache.coyote.http11.Http11Protocol|_ThreadID=10;|Initializing Coyote HTTP/1.1 on port 18080|#]
    [#|2005-08-23T11:45:20.790+0100|INFO|sun-appserver-pe8.0.0_01|org.apache.coyote.http11.Http11Protocol|_ThreadID=10;|Starting Coyote HTTP/1.1 on port 18080|#]
    [#|2005-08-23T11:45:21.125+0100|INFO|sun-appserver-pe8.0.0_01|org.apache.coyote.http11.Http11Protocol|_ThreadID=10;|Initializing Coyote HTTP/1.1 on port 11043|#]
    [#|2005-08-23T11:45:21.144+0100|INFO|sun-appserver-pe8.0.0_01|org.apache.coyote.http11.Http11Protocol|_ThreadID=10;|Starting Coyote HTTP/1.1 on port 11043|#]
    [#|2005-08-23T11:45:21.503+0100|INFO|sun-appserver-pe8.0.0_01|org.apache.coyote.http11.Http11Protocol|_ThreadID=10;|Initializing Coyote HTTP/1.1 on port 14848|#]
    [#|2005-08-23T11:45:21.537+0100|INFO|sun-appserver-pe8.0.0_01|org.apache.coyote.http11.Http11Protocol|_ThreadID=10;|Starting Coyote HTTP/1.1 on port 14848|#]
    [#|2005-08-23T11:45:21.989+0100|INFO|sun-appserver-pe8.0.0_01|javax.enterprise.resource.jms|_ThreadID=10;|JMS5023: JMS service successfully started. Instance Name = imqbroker, Home = [/opt/Creator/SunAppServer8/imq/bin].|#]
    [#|2005-08-23T11:45:22.003+0100|INFO|sun-appserver-pe8.0.0_01|javax.enterprise.system.tools.admin|_ThreadID=10;|[AutoDeploy] Enabling AutoDeployment service at :1124793922003|#]
    [#|2005-08-23T11:45:22.009+0100|INFO|sun-appserver-pe8.0.0_01|javax.enterprise.system.core|_ThreadID=10;|CORE5053: Application onReady complete.|#]
    [#|2005-08-23T11:45:22.012+0100|INFO|sun-appserver-pe8.0.0_01|javax.enterprise.system.core|_ThreadID=10;|Application server startup complete.|#]
    [#|2005-08-23T11:45:27.303+0100|INFO|sun-appserver-pe8.0.0_01|javax.enterprise.system.tools.admin|_ThreadID=11;|ADM1041:Sent the event to instance:[ResourceDeployEvent -- deploy jcp/RaveGenerated_1124793926_NFDBPool]|#]
    [#|2005-08-23T11:45:28.918+0100|INFO|sun-appserver-pe8.0.0_01|javax.enterprise.system.core|_ThreadID=11;|CORE5004: Resource Deployed: [jcp:RaveGenerated_1124793926_NFDBPool].|#]
    [#|2005-08-23T11:45:29.169+0100|INFO|sun-appserver-pe8.0.0_01|javax.enterprise.system.tools.admin|_ThreadID=11;|ADM1041:Sent the event to instance:[ResourceDeployEvent -- deploy jdbc/jdbc/NFDB]|#]
    [#|2005-08-23T11:45:29.365+0100|INFO|sun-appserver-pe8.0.0_01|javax.enterprise.system.core|_ThreadID=11;|CORE5004: Resource Deployed: [jdbc:jdbc/NFDB].|#]
    [#|2005-08-23T11:45:31.996+0100|INFO|sun-appserver-pe8.0.0_01|javax.enterprise.system.tools.deployment|_ThreadID=11;|DPL5109: EJBC - START of EJBC for [_linnfdb]|#]
    [#|2005-08-23T11:45:31.999+0100|INFO|sun-appserver-pe8.0.0_01|javax.enterprise.system.tools.deployment|_ThreadID=11;|Processing beans ...|#]
    [#|2005-08-23T11:45:32.032+0100|INFO|sun-appserver-pe8.0.0_01|javax.enterprise.system.tools.deployment|_ThreadID=11;|DPL5110: EJBC - END of EJBC for [_linnfdb]|#]
    [#|2005-08-23T11:45:32.915+0100|INFO|sun-appserver-pe8.0.0_01|javax.enterprise.system.tools.deployment|_ThreadID=11;|Total Deployment Time: 2082 msec, Total EJB Compiler Module Time: 37 msec, Portion spent EJB Compiling: 1%
    Breakdown of EJBC Module Time: Total Time for EJBC: 37 msec, CMP Generation: 0 msec (0%), Java Compilation: 0 msec (0%), RMI Compilation: 0 msec (0%), JAX-RPC Generation: 19 msec (51%),
    |#]
    [#|2005-08-23T11:45:32.928+0100|INFO|sun-appserver-pe8.0.0_01|javax.enterprise.system.tools.deployment|_ThreadID=11;|deployed with moduleid = _linnfdb|#]
    [#|2005-08-23T11:45:32.990+0100|INFO|sun-appserver-pe8.0.0_01|javax.enterprise.system.tools.admin|_ThreadID=11;|ADM1041:Sent the event to instance:[ModuleDeployEvent -- deploy web/_linnfdb]|#]
    [#|2005-08-23T11:45:33.275+0100|INFO|sun-appserver-pe8.0.0_01|javax.enterprise.system.tools.admin|_ThreadID=11;|ADM1041:Sent the event to instance:[ModuleDeployEvent -- enable web/_linnfdb]|#]
    [#|2005-08-23T11:45:33.352+0100|INFO|sun-appserver-pe8.0.0_01|javax.enterprise.system.container.web|_ThreadID=11;|WEB0100: Loading web module [_linnfdb] in virtual server [server] at [linnfdb]|#]
    [#|2005-08-23T11:45:34.837+0100|WARNING|sun-appserver-pe8.0.0_01|org.apache.commons.beanutils.MethodUtils|_ThreadID=11;|Cannot use JVM pre-1.4 access bug workaround die to restrictive security manager.|#]
    [#|2005-08-23T11:45:35.346+0100|WARNING|sun-appserver-pe8.0.0_01|org.apache.commons.digester.Digester|_ThreadID=11;|[ConverterRule]{faces-config/converter} Merge(null,java.math.BigDecimal)|#]
    [#|2005-08-23T11:45:35.364+0100|WARNING|sun-appserver-pe8.0.0_01|org.apache.commons.digester.Digester|_ThreadID=11;|[ConverterRule]{faces-config/converter} Merge(null,java.math.BigInteger)|#]
    [#|2005-08-23T11:45:37.265+0100|INFO|sun-appserver-pe8.0.0_01|com.sun.faces.config.ConfigureListener|_ThreadID=11;|Application object verification completed successfully|#]
    [#|2005-08-23T11:45:37.396+0100|INFO|sun-appserver-pe8.0.0_01|javax.enterprise.system.tools.admin|_ThreadID=11;|ADM1042:Status of dynamic reconfiguration event processing:[success]|#]
    [#|2005-08-23T11:46:28.167+0100|INFO|sun-appserver-pe8.0.0_01|javax.enterprise.system.stream.out|_ThreadID=12;|login successfull145|#]
    [#|2005-08-23T11:46:28.961+0100|INFO|sun-appserver-pe8.0.0_01|javax.enterprise.system.stream.out|_ThreadID=12;|
    assigned to user query|#]
    [#|2005-08-23T11:46:34.715+0100|SEVERE|sun-appserver-pe8.0.0_01|javax.enterprise.system.container.web|_ThreadID=12;|ApplicationDispatcher[/linnfdb] Servlet.service() for servlet jsp threw exception
    javax.faces.el.EvaluationException: java.lang.NullPointerException      
    at
    com.sun.faces.el.ValueBindingImpl.getValue(ValueBindingImpl.java:206)
         at com.sun.faces.el.ValueBindingImpl.getValue(ValueBindingImpl.java:154)
         at javax.faces.component.UISelectItems.getValue(UISelectItems.java:110)
         at com.sun.faces.util.Util.getSelectItems(Util.java:602)
         at com.sun.faces.renderkit.html_basic.MenuRenderer.getOptionNumber(MenuRenderer.java:488)
         at com.sun.faces.renderkit.html_basic.MenuRenderer.renderSelect(MenuRenderer.java:465)
         at com.sun.faces.renderkit.html_basic.MenuRenderer.encodeEnd(MenuRenderer.java:430)
         at javax.faces.component.UIComponentBase.encodeEnd(UIComponentBase.java:720)
         at com.sun.faces.renderkit.html_basic.HtmlBasicRenderer.encodeRecursive(HtmlBasicRenderer.java:443)
         at com.sun.faces.renderkit.html_basic.GroupRenderer.encodeChildren(GroupRenderer.java:130)
         at javax.faces.component.UIComponentBase.encodeChildren(UIComponentBase.java:701)
         at com.sun.faces.renderkit.html_basic.HtmlBasicRenderer.encodeRecursive(HtmlBasicRenderer.java:435)
         at com.sun.faces.renderkit.html_basic.TableRenderer.encodeBegin(TableRenderer.java:113)
         at javax.faces.component.UIComponentBase.encodeBegin(UIComponentBase.java:683)
         at javax.faces.component.UIData.encodeBegin(UIData.java:681)
         at javax.faces.webapp.UIComponentTag.encodeBegin(UIComponentTag.java:591)
         at javax.faces.webapp.UIComponentTag.doEndTag(UIComponentTag.java:543)
         at com.sun.faces.taglib.html_basic.DataTableTag.doEndTag(DataTableTag.java:491)
         at org.apache.jsp.NationalFaultsDataBase_jsp._jspx_meth_h_dataTable_0(NationalFaultsDataBase_jsp.java:581)
         at org.apache.jsp.NationalFaultsDataBase_jsp._jspx_meth_h_form_0(NationalFaultsDataBase_jsp.java:331)
         at org.apache.jsp.NationalFaultsDataBase_jsp._jspx_meth_f_view_0(NationalFaultsDataBase_jsp.java:291)
         at org.apache.jsp.NationalFaultsDataBase_jsp._jspService(NationalFaultsDataBase_jsp.java:182)
         at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:102)
         at javax.servlet.http.HttpServlet.service(HttpServlet.java:861)
         at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:282)
         at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:263)
         at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:210)
         at javax.servlet.http.HttpServlet.service(HttpServlet.java:861)
         at sun.reflect.GeneratedMethodAccessor84.invoke(Unknown Source)
         at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
         at java.lang.reflect.Method.invoke(Method.java:324)
         at org.apache.catalina.security.SecurityUtil$1.run(SecurityUtil.java:246)
         at java.security.AccessController.doPrivileged(Native Method)
         at javax.security.auth.Subject.doAsPrivileged(Subject.java:500)
         at org.apache.catalina.security.SecurityUtil.execute(SecurityUtil.java:268)
         at org.apache.catalina.security.SecurityUtil.doAsPrivilege(SecurityUtil.java:162)
         at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:236)
         at org.apache.catalina.core.ApplicationFilterChain.access$000(ApplicationFilterChain.java:55)
         at org.apache.catalina.core.ApplicationFilterChain$1.run(ApplicationFilterChain.java:145)
         at java.security.AccessController.doPrivileged(Native Method)
         at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:141)
         at org.apache.catalina.core.ApplicationDispatcher.invoke(ApplicationDispatcher.java:718)
         at org.apache.catalina.core.ApplicationDispatcher.processRequest(ApplicationDispatcher.java:478)
         at org.apache.catalina.core.ApplicationDispatcher.doForward(ApplicationDispatcher.java:413)
         at org.apache.catalina.core.ApplicationDispatcher.access$000(ApplicationDispatcher.java:77)
         at org.apache.catalina.core.ApplicationDispatcher$PrivilegedForward.run(ApplicationDispatcher.java:92)
         at java.security.AccessController.doPrivileged(Native Method)
         at org.apache.catalina.core.ApplicationDispatcher.forward(ApplicationDispatcher.java:319)
         at com.sun.faces.context.ExternalContextImpl.dispatch(ExternalContextImpl.java:322)
         at com.sun.faces.application.ViewHandlerImpl.renderView(ViewHandlerImpl.java:130)
         at com.sun.jsfcl.app.ViewHandlerImpl.renderView(ViewHandlerImpl.java:181)
         at com.sun.faces.lifecycle.RenderResponsePhase.execute(RenderResponsePhase.java:87)
         at com.sun.faces.lifecycle.LifecycleImpl.phase(LifecycleImpl.java:221)
         at com.sun.faces.lifecycle.LifecycleImpl.render(LifecycleImpl.java:117)
         at javax.faces.webapp.FacesServlet.service(FacesServlet.java:198)
         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.security.SecurityUtil$1.run(SecurityUtil.java:246)
         at java.security.AccessController.doPrivileged(Native Method)
         at javax.security.auth.Subject.doAsPrivileged(Subject.java:500)
         at org.apache.catalina.security.SecurityUtil.execute(SecurityUtil.java:268)
         at org.apache.catalina.security.SecurityUtil.doAsPrivilege(SecurityUtil.java:162)
         at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:236)
         at org.apache.catalina.core.ApplicationFilterChain.access$000(ApplicationFilterChain.java:55)
         at org.apache.catalina.core.ApplicationFilterChain$1.run(ApplicationFilterChain.java:145)
         at java.security.AccessController.doPrivileged(Native Method)
         at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:141)
         at linnfdb.data.SecurityCheckFilter.doFilter(SecurityCheckFilter.java:102)
         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.security.SecurityUtil$1.run(SecurityUtil.java:246)
         at java.security.AccessController.doPrivileged(Native Method)
         at javax.security.auth.Subject.doAsPrivileged(Subject.java:500)
         at org.apache.catalina.security.SecurityUtil.execute(SecurityUtil.java:268)
         at org.apache.catalina.security.SecurityUtil.doAsPrivilege(SecurityUtil.java:218)
         at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:188)
         at org.apache.catalina.core.ApplicationFilterChain.access$000(ApplicationFilterChain.java:55)
         at org.apache.catalina.core.ApplicationFilterChain$1.run(ApplicationFilterChain.java:145)
         at java.security.AccessController.doPrivileged(Native Method)
         at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:141)
         at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:220)
         at org.apache.catalina.core.StandardValveContext.invokeNext(StandardValveContext.java:109)
         at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:522)
         at org.apache.catalina.core.StandardContextValve.invokeInternal(StandardContextValve.java:214)
         at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:168)
         at org.apache.catalina.core.StandardValveContext.invokeNext(StandardValveContext.java:109)
         at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:522)
         at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:144)
         at org.apache.catalina.core.StandardValveContext.invokeNext(StandardValveContext.java:109)
         at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:133)
         at org.apache.catalina.core.StandardValveContext.invokeNext(StandardValveContext.java:107)
         at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:539)
         at org.apache.catalina.core.StandardValveContext.invokeNext(StandardValveContext.java:107)
         at com.sun.enterprise.webservice.EjbWebServiceValve.invoke(EjbWebServiceValve.java:134)
         at org.apache.catalina.core.StandardValveContext.invokeNext(StandardValveContext.java:107)
         at com.sun.enterprise.security.web.SingleSignOn.invoke(SingleSignOn.java:254)
         at org.apache.catalina.core.StandardValveContext.invokeNext(StandardValveContext.java:107)
         at com.sun.enterprise.web.VirtualServerValve.invoke(VirtualServerValve.java:209)
         at org.apache.catalina.core.StandardValveContext.invokeNext(StandardValveContext.java:107)
         at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:522)
         at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:114)
         at org.apache.catalina.core.StandardValveContext.invokeNext(StandardValveContext.java:109)
         at com.sun.enterprise.web.VirtualServerMappingValve.invoke(VirtualServerMappingValve.java:166)
         at org.apache.catalina.core.StandardValveContext.invokeNext(StandardValveContext.java:107)
         at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:522)
         at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:936)
         at org.apache.coyote.tomcat5.CoyoteAdapter.service(CoyoteAdapter.java:165)
         at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:683)
         at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.processConnection(Http11Protocol.java:604)
         at org.apache.tomcat.util.net.TcpWorkerThread.runIt(PoolTcpEndpoint.java:542)
         at org.apache.tomcat.util.threads.ThreadPool$ControlRunnable.run(ThreadPool.java:647)
         at java.lang.Thread.run(Thread.java:534)
    Caused by: java.lang.NullPointerException
         at com.sun.jsfcl.data.ResultSetPropertyResolver$ColumnData.getSelectItems(ResultSetPropertyResolver.java:303)
         at com.sun.jsfcl.data.ResultSetPropertyResolver.getValue(ResultSetPropertyResolver.java:61)
         at com.sun.faces.el.impl.ArraySuffix.evaluate(ArraySuffix.java:167)
         at com.sun.faces.el.impl.ComplexValue.evaluate(ComplexValue.java:151)
         at com.sun.faces.el.impl.ExpressionEvaluatorImpl.evaluate(ExpressionEvaluatorImpl.java:243)
         at com.sun.faces.el.ValueBindingImpl.getValue(ValueBindingImpl.java:173)
         ... 115 more
    |#]
    any help will be greatly appreciated. Pleaseeeeeeeeeeeeee can some get back to me.
    Cheers
    kumar

    hi,
    I just found that this exception is thrown from function
    public UIViewRoot createView(FacesContext context, String viewId) {
    UIViewRoot viewRoot = handler.createView(context, viewId);
    context.getExternalContext().getRequestMap().put(CREATED_VIEW, viewId);
    setupPageBean(context, viewRoot);
    return viewRoot;
    in viewHandlerImpl.java.
    Has anyone got ideas about this???
    Any help will be greatly appreciated.
    cheers
    kush

  • Development Standards for BW implementation

    Hi all,
    Any one has any materials on development standards for BW implementation - with any special attention to BI 7.0 implementation?
    Thanks for your assistance. Contributions will be rewarded with points.
    Regards,
    Uche

    hi Uche,
    check if helps
    Multi-Dimensional Modeling with SAP NetWeaver BI
    https://www.sdn.sap.com/irj/servlet/prt/portal/prtroot/docs/library/uuid/6ce7b0a4-0b01-0010-52ac-a6e813c35a84
    Modeling the Data Warehouse Layer with BI
    https://www.sdn.sap.com/irj/servlet/prt/portal/prtroot/docs/library/uuid/3668618d-0c01-0010-1ab5-aa75c3a4dfc2
    Frontend Design Guidelines - SAP BI in SAP NetWeaver 2004s
    https://www.sdn.sap.com/irj/servlet/prt/portal/prtroot/docs/library/uuid/58fd9183-0e01-0010-f183-fdc9019f77ab
    Enterprise Reporting, Query, and Analysis - Developers Guide
    https://www.sdn.sap.com/irj/servlet/prt/portal/prtroot/docs/library/uuid/0901c9bb-0601-0010-49ab-c1770c527673
    check
    https://www.sdn.sap.com/irj/sdn/developerareas/bi
    'key topics'

  • No servlet class has been specified for servlet null

    Hi,
    I�m trying to bend tomcat in my own application. Therefore I�m using the Embedded Tomcat version 5.5.23.
    I have started only a server, engine, host and context, so I have a server without the sockets etc. this because it has to become a test-application for the web-app of the company.
    The server starts gracefully, but when I call context.invoke(request,response) I get this error:
    SEVERE: Allocate exception for servlet null
    With this stacktrace:
    javax.servlet.ServletException: No servlet class has been specified for servlet null
    at org.apache.catalina.core.StandardWrapper.loadServlet(StandardWrapper.java:1016)
    at org.apache.catalina.core.StandardWrapper.allocate(StandardWrapper.java:791)
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:127)
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:174)
    at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:870)
    at nl.realworks.embedTomcat.EmbedTomcat.invoke(EmbedTomcat.java:74)
    at nl.realworks.embedTomcat.StartEmbedTomcat.main(StartEmbedTomcat.java:29)
    Exception in thread "main" java.lang.NullPointerException
    at org.apache.catalina.connector.Request.setAttribute(Request.java:1383)
    at org.apache.catalina.core.StandardWrapperValve.exception(StandardWrapperValve.java:331)
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:145)
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:174)
    at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:870)
    at nl.realworks.embedTomcat.EmbedTomcat.invoke(EmbedTomcat.java:74)
    at nl.realworks.embedTomcat.StartEmbedTomcat.main(StartEmbedTomcat.java:29)
    does anyone has a idea what the cause of this problem is? The request I send is �GET /index.jsp� using a MockHttpServletRequest of the spring framework. I convert the mockhttpservletrequest to a org.apache.cataline.connecor.Request. and that works.
    The code in tomcat where the error is caused by:
    // Complain if no servlet class has been specified
    if (actualClass == null) {
    unavailable(null);
    throw new ServletException
    (sm.getString("standardWrapper.notClass", getName()));
    Thanks in advance.
    Auke Noppe

    Tobias
    Yes , you are correct. We dont need to replicate DDIC tables for direct BW replication. This was the first time we were working with BW on Hana and never installed DMIS component on that system. The error was gone after we put the addon.
    Mahesh Shetty

  • Thread pools for execute queues

    We've set up thread pools for several execute queues dedicated to high-load servlets
    in our application. Once in a while, we get into a condition in which none of
    these threads are available and then the threads never become available - we have
    to restart the server.
    I realize that this is a pretty generic description of the problem :-) but I wonder
    if anyone else has encountered this and has an idea what might be causing it ?
    Right now I am guessing that something in our code causes a resource contention
    that eventually deadlocks all the threads. But that is just a guess.

    Ethan,
    "Ethan Allen" <[email protected]> wrote in message
    news:3e0220a1$[email protected]..
    Thanks, Dimitri and Slava !
    I will do this and learn a little emore ...FYI, there is a web site dedicated to weblogic documentation -
    http://e-docs.bea.com/
    Pick your server version, go to "Search", type "thread dump".
    Regards,
    Slava Imeshev
    >
    ethan
    "Slava Imeshev" <[email protected]> wrote:
    Hi Ethan,
    For windows press <Ctrl>+<Break> in the server shell window,
    for *nix send kill -3 {server PID}.
    Regards,
    Slava Imeshev
    "Ethan Allen" <[email protected]> wrote in message
    news:3e020fb4$[email protected]..
    Thanks for your reply, Dimitri.
    We have not looked at thread dumps. How may we do this ?
    Ethan
    "Dimitri I. Rakitine" <[email protected]> wrote:
    Did you try looking at thread dumps when this happens ?
    Ethan Allen <[email protected]> wrote:
    We've set up thread pools for several execute queues dedicated to
    high-load
    servlets
    in our application. Once in a while, we get into a condition in
    which
    none of
    these threads are available and then the threads never become
    available
    - we have
    to restart the server.
    I realize that this is a pretty generic description of the problem:-) but I wonder
    if anyone else has encountered this and has an idea what might be
    causing
    it ?
    Right now I am guessing that something in our code causes a
    resource
    contention
    that eventually deadlocks all the threads. But that is just a
    guess.
    >>>>
    Dimitri

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