这是俺的错误信息:HTTP Status 500 - --------------------------------------------------------------------------------type Exception reportmessage description The server encountered an internal error () that prevented it from fulfilling this request.exception org.apache.jasper.JasperException: Unable to compile class for JSPAn error occurred at line: -1 in the jsp file: nullGenerated servlet error: [javac] Since fork is true, ignoring compiler setting. [javac] Compiling 1 source file [javac] Since fork is true, ignoring compiler setting. [javac] D:\Apache Group\Tomcat 4.1\work\Standalone\localhost\jsp\helloBeans_jsp.java:47: package test does not exist [javac] test.helloBeans helloBean = null; [javac] ^ [javac] D:\Apache Group\Tomcat 4.1\work\Standalone\localhost\jsp\helloBeans_jsp.java:49: package test does not exist [javac] helloBean = (test.helloBeans) pageContext.getAttribute("helloBean", PageContext.SESSION_SCOPE); [javac] ^ [javac] D:\Apache Group\Tomcat 4.1\work\Standalone\localhost\jsp\helloBeans_jsp.java:52: package test does not exist [javac] helloBean = (test.helloBeans) java.beans.Beans.instantiate(this.getClass().getClassLoader(), "test.helloBeans"); [javac] ^ [javac] 3 errors at org.apache.jasper.compiler.DefaultErrorHandler.javacError(DefaultErrorHandler.java:130) at org.apache.jasper.compiler.ErrorDispatcher.javacError(ErrorDispatcher.java:293) at org.apache.jasper.compiler.Compiler.generateClass(Compiler.java:351) at org.apache.jasper.compiler.Compiler.compile(Compiler.java:368) at org.apache.jasper.JspCompilationContext.compile(JspCompilationContext.java:473) at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:190) at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:295) at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:241) at javax.servlet.http.HttpServlet.service(HttpServlet.java:853) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:247) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:193) at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:256) at org.apache.catalina.core.StandardPipeline$StandardPipelineValveContext.invokeNext(StandardPipeline.java:643) at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:480) at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:995) at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191) at org.apache.catalina.core.StandardPipeline$StandardPipelineValveContext.invokeNext(StandardPipeline.java:643) at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:480) at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:995) at org.apache.catalina.core.StandardContext.invoke(StandardContext.java:2415) at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:180) at org.apache.catalina.core.StandardPipeline$StandardPipelineValveContext.invokeNext(StandardPipeline.java:643) at org.apache.catalina.valves.ErrorDispatcherValve.invoke(ErrorDispatcherValve.java:171) at org.apache.catalina.core.StandardPipeline$StandardPipelineValveContext.invokeNext(StandardPipeline.java:641) at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:172) at org.apache.catalina.core.StandardPipeline$StandardPipelineValveContext.invokeNext(StandardPipeline.java:641) at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:480) at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:995) at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:174) at org.apache.catalina.core.StandardPipeline$StandardPipelineValveContext.invokeNext(StandardPipeline.java:643) at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:480) at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:995) at org.apache.coyote.tomcat4.CoyoteAdapter.service(CoyoteAdapter.java:223) at org.apache.jk.server.JkCoyoteHandler.invoke(JkCoyoteHandler.java:261) at org.apache.jk.common.HandlerRequest.invoke(HandlerRequest.java:360) at org.apache.jk.common.ChannelSocket.invoke(ChannelSocket.java:604) at org.apache.jk.common.ChannelSocket.processConnection(ChannelSocket.java:562) at org.apache.jk.common.SocketConnection.runIt(ChannelSocket.java:679) at org.apache.tomcat.util.threads.ThreadPool$ControlRunnable.run(ThreadPool.java:619) at java.lang.Thread.run(Thread.java:536)--------------------------------------------------------------------------------Apache Tomcat/4.1.22
javabean类中必须要有package
servlet还需要配置web.xml:
<servlet>
<servlet-name>watermelon</servlet-name>//name
<servlet-class>myservlets.watermelon</servlet-class>//package.name
</servlet>
<servlet-mapping>
<servlet-name>watermelon</servlet-name>
<url-pattern>/fruit/summer/*</url-pattern>//Servlet映射
</servlet-mapping>调用的Servlet
http://host:port/mywebapp/fruit/summer/index.html watermelon
下边是配置web.xml(web.xml在classes下):
<?xml version="1.0" encoding="ISO-8859-1"?><!DOCTYPE web-app
PUBLIC "-//Sun Microsystems, Inc.//DTD Web Application 2.2//EN"
"http://java.sun.com/j2ee/dtds/web-app_2_2.dtd">
<web-app> <display-name>jspsmartupload</display-name>
<servlet id="Servlet_1">
<servlet-name>servlet name</servlet-name>
<description>description</description>
<servlet-class>servlet path</servlet-class>
</servlet>
<servlet-mapping id="ServletMapping_1">
<servlet-name>servlet name</servlet-name>
<url-pattern>*.go</url-pattern>
</servlet-mapping>
</web-app>
http://host:port/mywebapp/servlet/servletname
-----------------------------------------------
//这是java文件
package test;class helloBeans
{
private String str = "hello Beans!!!"; public String get()
{
return str;
}
}
--------------------------------------------------
//这是jsp文件
<html>
<head>
<title>javaBeans</title>
</head>
<body>
<jsp:useBean id="helloBean" scope="session" class="test.helloBeans"/>
<hr>
<%
out.print(helloBean.get());
%>
</body>
</html>
我也急用这个东西!!
[javac] Since fork is true, ignoring compiler setting.
[javac] Compiling 1 source file
[javac] Since fork is true, ignoring compiler setting.
[javac] D:\Apache Group\Tomcat 4.1\work\Standalone\localhost\jsp\helloBeans_jsp.java:47: package test does not exist
[javac] test.helloBeans helloBean = null;
[javac] ^
[javac] D:\Apache Group\Tomcat 4.1\work\Standalone\localhost\jsp\helloBeans_jsp.java:49: package test does not exist
[javac] helloBean = (test.helloBeans) pageContext.getAttribute("helloBean", PageContext.SESSION_SCOPE);
[javac] ^
[javac] D:\Apache Group\Tomcat 4.1\work\Standalone\localhost\jsp\helloBeans_jsp.java:52: package test does not exist
[javac] helloBean = (test.helloBeans) java.beans.Beans.instantiate(this.getClass().getClassLoader(), "test.helloBeans");
[javac] ^
[javac] 3 errors at org.apache.jasper.compiler.DefaultErrorHandler.javacError(DefaultErrorHandler.java:130)
at org.apache.jasper.compiler.ErrorDispatcher.javacError(ErrorDispatcher.java:293)
at org.apache.jasper.compiler.Compiler.generateClass(Compiler.java:351)
at org.apache.jasper.compiler.Compiler.compile(Compiler.java:368)
at org.apache.jasper.JspCompilationContext.compile(JspCompilationContext.java:473)
at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:190)
at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:295)
at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:241)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:853)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:247)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:193)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:256)
at org.apache.catalina.core.StandardPipeline$StandardPipelineValveContext.invokeNext(StandardPipeline.java:643)
at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:480)
at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:995)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191)
at org.apache.catalina.core.StandardPipeline$StandardPipelineValveContext.invokeNext(StandardPipeline.java:643)
at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:480)
at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:995)
at org.apache.catalina.core.StandardContext.invoke(StandardContext.java:2415)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:180)
at org.apache.catalina.core.StandardPipeline$StandardPipelineValveContext.invokeNext(StandardPipeline.java:643)
at org.apache.catalina.valves.ErrorDispatcherValve.invoke(ErrorDispatcherValve.java:171)
at org.apache.catalina.core.StandardPipeline$StandardPipelineValveContext.invokeNext(StandardPipeline.java:641)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:172)
at org.apache.catalina.core.StandardPipeline$StandardPipelineValveContext.invokeNext(StandardPipeline.java:641)
at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:480)
at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:995)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:174)
at org.apache.catalina.core.StandardPipeline$StandardPipelineValveContext.invokeNext(StandardPipeline.java:643)
at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:480)
at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:995)
at org.apache.coyote.tomcat4.CoyoteAdapter.service(CoyoteAdapter.java:223)
at org.apache.jk.server.JkCoyoteHandler.invoke(JkCoyoteHandler.java:261)
at org.apache.jk.common.HandlerRequest.invoke(HandlerRequest.java:360)
at org.apache.jk.common.ChannelSocket.invoke(ChannelSocket.java:604)
at org.apache.jk.common.ChannelSocket.processConnection(ChannelSocket.java:562)
at org.apache.jk.common.SocketConnection.runIt(ChannelSocket.java:679)
at org.apache.tomcat.util.threads.ThreadPool$ControlRunnable.run(ThreadPool.java:619)
at java.lang.Thread.run(Thread.java:536)--------------------------------------------------------------------------------Apache Tomcat/4.1.22
建一个文件夹,那么在bean的java文件开头加package 文件夹名;