使用bean:writer标签时，报这样的错误是由什么原因造成的?

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

javax.servlet.ServletException: org/apache/commons/beanutils/PropertyUtils
org.apache.jasper.runtime.PageContextImpl.doHandlePageException(PageContextImpl.java:825)
org.apache.jasper.runtime.PageContextImpl.handlePageException(PageContextImpl.java:758)
org.apache.jsp.cart_jsp._jspService(cart_jsp.java:148)
org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:94)
javax.servlet.http.HttpServlet.service(HttpServlet.java:810)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:298)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:292)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:236)
javax.servlet.http.HttpServlet.service(HttpServlet.java:810)


root cause

java.lang.NoClassDefFoundError: org/apache/commons/beanutils/PropertyUtils
org.apache.struts.util.RequestUtils.lookup(RequestUtils.java:952)
org.apache.struts.taglib.bean.WriteTag.doStartTag(WriteTag.java:286)
org.apache.jsp.cart_jsp._jspx_meth_bean_write_0(cart_jsp.java:165)
org.apache.jsp.cart_jsp._jspService(cart_jsp.java:122)
org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:94)
javax.servlet.http.HttpServlet.service(HttpServlet.java:810)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:298)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:292)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:236)
javax.servlet.http.HttpServlet.service(HttpServlet.java:810)


note The full stack trace of the root cause is available in the Apache Tomcat/5.0.24 logs.


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Apache Tomcat/5.0.24