jquery jsp 删除和修改。? 400 报错_问答-阿里云开发者社区

jquery jsp 删除和修改。? 400 报错 <%@ page language="java" import="java.util." import="java.sql." pageEncoding="utf-8"%>
<jsp:useBean id="dbConn" class="pack_convert.DBConnXmgl"/>
<jsp:useBean id="projectinfo" class="net.gvsun.database.ProjectInfo"/>
<%@ page session="true" %>

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<%
String id = request.getParameter("id");
int aid = Integer.parseInt(id);
boolean bol = projectinfo.deleteCash(aid);
    if(bol){
           out.println("{"success":"true","msg":"添加成功！"}");
    }else{
           out.println("{"failure":"failure","msg":"出错了，请重新操作！"}");
    }
response.setHeader("Refresh","1; URL=../../projectFinance.jsp");//1秒后自动跳转页面
//out.println(bol);//打印结果
dbConn.releaseConn();

这行报以下错误：java.lang.NumberFormatException: For input string: "undefined"
    at java.lang.NumberFormatException.forInputString(NumberFormatException.java:48)
    at java.lang.Integer.parseInt(Integer.java:449)
    at java.lang.Integer.parseInt(Integer.java:499)
    at org.apache.jsp.projectinfo.jsp.deleteCash_jsp._jspService(deleteCash_jsp.java:82)
    at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
    at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:386)
    at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:313)
    at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:260)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:233)
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191)
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:127)
    at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102)
    at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:298)
    at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:859)
    at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:588)
    at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:489)
    at java.lang.Thread.run(Thread.java:662)