at org.apache.jsp.result_jsp._jspService(result_jsp.java:66)HTTP Status 500 -type Exception reportmessagedescription The server encountered an internal error () that prevented it from fulfilling this request.exceptionorg.apache.jasper.JasperException

Stacktrace:
\x05org.apache.jasper.servlet.JspServletWrapper.handleJspException(JspServletWrapper.java:521)
\x05org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:430)
\x05org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:313)
\x05org.apache.jasper.servlet.JspServlet.service(JspServlet.java:260)
\x05javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
root cause
java.lang.NullPointerException
\x05org.apache.jsp.result_jsp._jspService(result_jsp.java:66)
\x05org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70)
\x05javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
\x05org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:388)
\x05org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:313)
\x05org.apache.jasper.servlet.JspServlet.service(JspServlet.java:260)
\x05javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
note The full stack trace of the root cause is available in the
Apache Tomcat/6.0.35 logs.
九月 04,2013 9:26:10 上午 org.apache.catalina.core.StandardWrapperValve invoke
SEVERE:Servlet.service() for servlet jsp threw exception
java.lang.NullPointerException
运行result.jsp报错,烦请大家帮忙看看具体是什么错误,

at org.apache.jsp.result_jsp._jspService(result_jsp.java:66)HTTP Status 500 -type Exception reportmessagedescription The server encountered an internal error () that prevented it from fulfilling this request.exceptionorg.apache.jasper.JasperException
JSP页面第13行的for循环没有关闭.应该如下：

   for(int i=0; i < books.size(); i++){
        Book book = books.get(i);

   }