jsp 问题啊 高手求救啊

运行后报错......  小弟急死了了 
都一个礼拜了 还没解决
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message description The server encountered an internal error () that prevented it from fulfilling this request.exception org.apache.jasper.JasperException: An exception occurred processing JSP page /list.jsp at line 2320:   String time = formatDate.format(new Date());
21:  %>
22:  <% 
23:    int p=Integer.parseInt(request.getParameter("page"));
24:    int bId=Integer.parseInt(request.getParameter("boardId"));
25:    int nextp=p,prep=p;
26:    TopicInfoDAO tdao=new TopicInfoDAO();
Stacktrace:
org.apache.jasper.servlet.JspServletWrapper.handleJspException(JspServletWrapper.java:524)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:435)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:320)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:266)
javax.servlet.http.HttpServlet.service(HttpServlet.java:803)
root cause java.lang.NumberFormatException: null
java.lang.Integer.parseInt(Integer.java:417)
java.lang.Integer.parseInt(Integer.java:499)
org.apache.jsp.list_jsp._jspService(list_jsp.java:81)
org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70)
javax.servlet.http.HttpServlet.service(HttpServlet.java:803)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:393)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:320)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:266)
javax.servlet.http.HttpServlet.service(HttpServlet.java:803)-------------------------------------------------------------------------