[求助]运行文件管理程序时出现的错误。

我是新手，看不懂这些错误，请大虾们帮忙解释一下，先谢谢了！

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 load class for JSP
	org.apache.jasper.JspCompilationContext.load(JspCompilationContext.java:591)
	org.apache.jasper.servlet.JspServletWrapper.getServlet(JspServletWrapper.java:137)
	org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:308)
	org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:295)
	org.apache.jasper.servlet.JspServlet.service(JspServlet.java:245)
	javax.servlet.http.HttpServlet.service(HttpServlet.java:802)

root cause

java.lang.ClassNotFoundException: org.apache.jsp.admin_jsp
	java.net.URLClassLoader$1.run(Unknown Source)
	java.security.AccessController.doPrivileged(Native Method)
	java.net.URLClassLoader.findClass(Unknown Source)
	org.apache.jasper.servlet.JasperLoader.loadClass(JasperLoader.java:156)
	org.apache.jasper.servlet.JasperLoader.loadClass(JasperLoader.java:69)
	org.apache.jasper.JspCompilationContext.load(JspCompilationContext.java:589)
	org.apache.jasper.servlet.JspServletWrapper.getServlet(JspServletWrapper.java:137)
	org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:308)
	org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:295)
	org.apache.jasper.servlet.JspServlet.service(JspServlet.java:245)
	javax.servlet.http.HttpServlet.service(HttpServlet.java:802)

note The full stack trace of the root cause is available in the Apache Tomcat/5.5.4 logs.

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先看网页报的是什么编号的错？看情况像是404错……
----------------解决方案--------------------------------------------------------