谁给我看看这代码有什么问题？？？

Question

执行后显示。这怎么回事呢？？exception javax.servlet.ServletException: Illegal operation on empty result set.
org.apache.jasper.runtime.PageContextImpl.doHandlePageException(PageContextImpl.java:825)
org.apache.jasper.runtime.PageContextImpl.handlePageException(PageContextImpl.java:758)
org.apache.jsp.admindata_jsp._jspService(admindata_jsp.java:152)
org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:94)
javax.servlet.http.HttpServlet.service(HttpServlet.java:802)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:324)
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:802)
root cause java.sql.SQLException: Illegal operation on empty result set.
com.mysql.jdbc.ResultSet.checkRowPos(ResultSet.java:693)
com.mysql.jdbc.ResultSet.getStringInternal(ResultSet.java:4832)
com.mysql.jdbc.ResultSet.getString(ResultSet.java:4810)
com.mysql.jdbc.ResultSet.getString(ResultSet.java:4826)
org.apache.jsp.admindata_jsp._jspService(admindata_jsp.java:123)
org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:94)
javax.servlet.http.HttpServlet.service(HttpServlet.java:802)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:324)
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:802)
note The full stack trace of the root cause is available in the Apache Tomcat/5.0.28 logs.

Answer 1

在你的javascript脚本中不能加入这类<%  String sql="select * from user_admin where user='"+user+"'"; %>服务端的代码.

Answer 2

ResultSet rs=statement.executeQuery(sql);
user=rs.getString("user");在用rs之前要执行rs.next();
因为默认rs的游标是在所有记录之前的

Answer 3

在用这句代码前user=rs.getString("user");
要先判断rs是否为空

Answer 4

user=rs.getString("user");
 telephone=rs.getString("telephone"); 
==>if(rs.next()){
  user=rs.getString("user");
  telephone=rs.getString("telephone"); 
}