我电脑里原来有JDK，安装完tomcat后打开"http://localhost:8080/index.jsp"后却没显示欢迎信息，显示的是下面的东西：哪位朋友帮我看看应该怎么解决？急啊，谢了！
HTTP Status 500 - 

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type Exception report

message 

description The server encountered an internal error () that prevented it from fulfilling this request.

exception 

org.apache.jasper.JasperException: Unable to compile class for JSP

An error occurred at line: -1 in the jsp file: null

Generated servlet error:
    [javac] Compiling 1 source file



    at org.apache.jasper.compiler.DefaultErrorHandler.javacError(DefaultErrorHandler.java:85)
    at org.apache.jasper.compiler.ErrorDispatcher.javacError(ErrorDispatcher.java:248)
    at org.apache.jasper.compiler.Compiler.generateClass(Compiler.java:315)
    at org.apache.jasper.compiler.Compiler.compile(Compiler.java:328)
    at org.apache.jasper.JspCompilationContext.compile(JspCompilationContext.java:427)
    at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:142)
    at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:240)
    at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:187)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:809)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:200)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:146)
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:209)
    at org.apache.catalina.core.StandardPipeline$StandardPipelineValveContext.invokeNext(StandardPipeline.java:596)
    at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:433)
    at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:948)
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:144)
    at org.apache.catalina.core.StandardPipeline$StandardPipelineValveContext.invokeNext(StandardPipeline.java:596)
    at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:433)
    at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:948)
    at org.apache.catalina.core.StandardContext.invoke(StandardContext.java:2358)
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:133)
    at org.apache.catalina.core.StandardPipeline$StandardPipelineValveContext.invokeNext(StandardPipeline.java:596)
    at org.apache.catalina.valves.ErrorDispatcherValve.invoke(ErrorDispatcherValve.java:118)
    at org.apache.catalina.core.StandardPipeline$StandardPipelineValveContext.invokeNext(StandardPipeline.java:594)
    at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:116)
    at org.apache.catalina.core.StandardPipeline$StandardPipelineValveContext.invokeNext(StandardPipeline.java:594)
    at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:433)
    at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:948)
    at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:127)
    at org.apache.catalina.core.StandardPipeline$StandardPipelineValveContext.invokeNext(StandardPipeline.java:596)
    at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:433)
    at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:948)
    at org.apache.coyote.tomcat4.CoyoteAdapter.service(CoyoteAdapter.java:152)
    at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:799)
    at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.processConnection(Http11Protocol.java:705)
    at org.apache.tomcat.util.net.TcpWorkerThread.runIt(PoolTcpEndpoint.java:577)
    at org.apache.tomcat.util.threads.ThreadPool$ControlRunnable.run(ThreadPool.java:683)
    at java.lang.Thread.run(Thread.java:595)



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Apache Tomcat/4.1.31