LinkageError: loader constraint violation

[larsolino]

I'm running the maven app like described in the README file with mvn tomcat:run. My environment is Mac OS X 10.6.8 with Java 1.6.0_26. When accessing the application through the browser at address http://localhost:8080/spring-mvc-showcase it get the following exception:

INFO: Starting Coyote HTTP/1.1 on http-8080
DEBUG: org.springframework.web.servlet.DispatcherServlet - DispatcherServlet with name 'appServlet' processing GET request for [/spring-mvc-showcase/]
DEBUG: org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerMapping - Looking up handler method for path /
DEBUG: org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerMapping - Did not find handler method for [/]
DEBUG: org.springframework.web.servlet.handler.SimpleUrlHandlerMapping - Mapping [/] to HandlerExecutionChain with handler [org.springframework.web.servlet.mvc.ParameterizableViewController@5994a1e9] and 1 interceptor
DEBUG: org.springframework.web.servlet.DispatcherServlet - Last-Modified value for [/spring-mvc-showcase/] is: -1
DEBUG: org.springframework.web.servlet.DispatcherServlet - Rendering view [org.springframework.web.servlet.view.JstlView: name 'home'; URL [/WEB-INF/views/home.jsp]] in DispatcherServlet with name 'appServlet'
DEBUG: org.springframework.web.servlet.view.JstlView - Forwarding to resource [/WEB-INF/views/home.jsp] in InternalResourceView 'home'
11.07.2011 21:11:11 org.apache.catalina.core.ApplicationDispatcher invoke
SCHWERWIEGEND: Servlet.service() for servlet jsp threw exception
java.lang.LinkageError: loader constraint violation: when resolving interface method "javax.servlet.jsp.JspApplicationContext.getExpressionFactory()Ljavax/el/ExpressionFactory;" the class loader (instance of org/apache/jasper/servlet/JasperLoader) of the current class, org/apache/jsp/WEB_002dINF/views/home_jsp, and the class loader (instance of org/codehaus/plexus/classworlds/realm/ClassRealm) for resolved class, javax/servlet/jsp/JspApplicationContext, have different Class objects for the type javax/el/ExpressionFactory used in the signature
at org.apache.jsp.WEB_002dINF.views.home_jsp._jspInit(home_jsp.java:25)
at org.apache.jasper.runtime.HttpJspBase.init(HttpJspBase.java:52)
at org.apache.jasper.servlet.JspServletWrapper.getServlet(JspServletWrapper.java:159)
at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:329)
at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:313)
at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:260)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.apache.catalina.core.ApplicationDispatcher.invoke(ApplicationDispatcher.java:646)
at org.apache.catalina.core.ApplicationDispatcher.processRequest(ApplicationDispatcher.java:436)
at org.apache.catalina.core.ApplicationDispatcher.doForward(ApplicationDispatcher.java:374)
at org.apache.catalina.core.ApplicationDispatcher.forward(ApplicationDispatcher.java:302)
at org.springframework.web.servlet.view.InternalResourceView.renderMergedOutputModel(InternalResourceView.java:238)
at org.springframework.web.servlet.view.AbstractView.render(AbstractView.java:250)
at org.springframework.web.servlet.DispatcherServlet.render(DispatcherServlet.java:1120)
at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:890)
at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:792)
at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:851)
at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:756)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:617)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.springframework.mvc.extensions.flash.FlashMapFilter.doFilterInternal(FlashMapFilter.java:33)
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:76)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:233)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:127)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:298)
at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:857)
at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:588)
at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:489)
at java.lang.Thread.run(Thread.java:680)

I guess it has something to do with the javax.el library?

[larsolino]

It works when changing the pom:

org.apache.tomcat el-api 6.0.32 provided org.apache.tomcat jasper-el 6.0.32 provided

    <!--
    <dependency>
        <groupId>javax.servlet.jsp.jstl</groupId>
        <artifactId>jstl-api</artifactId>
        <version>1.2</version>
    </dependency>       
    <dependency>
        <groupId>org.glassfish.web</groupId>
        <artifactId>jstl-impl</artifactId>
        <version>1.2</version>
    </dependency>-->

Maven complains about missing artifacts when installing but on my machine it's working now.

[larsolino]

Github removed the XML formatting above...

[kdonald]

I don't understand this one. Those two jstl dependencies are right there in the Maven Central repository and neither el-api or jasper-el are on the classpath of mvc-showcase. The definition of those provided dependencies shouldn't be necessary and the JSTL dependencies should resolve. Perhaps try cleaning out your maven 2 repo and trying again with the original pom.

[marioosh-net]

mvn tomcat:run works for me if i comment out jstl-api and jstl-impl and place:

    <dependency>
        <groupId>javax.servlet</groupId>
        <artifactId>jstl</artifactId>
        <version>1.2</version>
    </dependency>

[rstoyanchev]

This should work now via a30e404.