Страница Jsp, показывающая java.lang.numberformatexception: null
сэр, я создал страницу jsp для формы boq, чтобы обновить записи boq.
я написал бизнес-логику на странице jsp, чтобы сначала выбрать записи на основе идентификатора. когда я запускаю эту страницу.
затем страница, показывающая
java.lang.NumberFormatException: null
настоящим я написал всю кодировку целиком:
--------
BOQ-Form.jsp-----------------
<%@page import="java.sql.SQLException"%>
<%@page import="java.sql.ResultSet"%>
<%@page import="java.sql.Statement"%>
<%@page import="com.mvc.util.DBConnection"%>
<%@page import="java.sql.Connection"%>
<%@ page language="java" contentType="text/html; charset=ISO-8859-1" pageEncoding="ISO-8859-1"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<title>Edit BOQ</title>
<meta charset="utf-8">
<meta name="viewport" content="width=device-width, initial-scale=1">
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/css/bootstrap.min.css">
<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
<script src="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/js/bootstrap.min.js"></script>
<title>Update BOQ</title>
</head>
<body>
<%!int _ID;
String _HsnCode, _ISHsnCodeConfirmed, GST_RATE, IS_GST_RATECONFIRMED,item_desc,UNIT,_QTY,_P,W,_V;
%>
<%
try
{
_ID = Integer.parseInt(request.getParameter("id"));
Connection con = DBConnection.createConnection();
Statement stmt = con.createStatement();
ResultSet rst = stmt.executeQuery("select * from boq where id="+_ID+"");
if(rst.next())
{
_HsnCode = rst.getString("hsn_Code");
_ISHsnCodeConfirmed = rst.getString("is_hsnConfirmed");
GST_RATE = rst.getString("gst_rate");
IS_GST_RATECONFIRMED= rst.getString("is_gstRate_confirmed");
item_desc = rst.getString("item_Description");
UNIT = rst.getString("Unit");
_QTY = rst.getString("Qty");
_P = rst.getString("p");
W = rst.getString("w");
_V = rst.getString("v");
}
}
catch(SQLException e)
{
out.println(e);
response.sendRedirect("/error.jsp");
}
%>
<center>
<div class="container">
<center>
<h2>Update</h2>
</center><hr>
<form action="BoqServlet" method="post">
<table class="table table-bordered" style="width:60%; ">
<thead>
<tr>
<th colspan="2"><center>BOQ Update form</center></th>
</tr>
</thead>
<tbody>
<input type="hidden" name="id" value="<%=_ID%>"/>
<tr>
<td>Hsn Code</td>
<td><input type="text" name="_hsn_Code" required="required" class="form-control" value="<%= _HsnCode %>"></td>
</tr>
<tr>
<td> HSN code confirmation </td>
<td><input type="text" name="_isHSN_CodeConfirmed" required="required" class="form-control" value="<%=_ISHsnCodeConfirmed %>></td>
</tr>
<tr>
<td>GST Rate</td>
<td><input type="text" name="_gst_RATE" required="required" class="form-control" value="<%=GST_RATE%>"></td>
</tr>
<tr>
<td>GST Rate Confirmation</td>
<td><input type="text" name="GST_rate_Confirmation" required="required" class="form-control" value="<%=IS_GST_RATECONFIRMED %>"></td>
</tr>
<tr>
<td>Item Description</td>
<td><input type="text" name="_ItemDesc" required="required" class="form-control" value="<%=item_desc %>"></td>
</tr>
<tr>
<td>Units</td>
<td><input type="text" name="_unit_" required="required" class="form-control" value="<%=UNIT %>>"</td>
</tr>
<tr>
<td>Quantity</td>
<td><input type="text" name="_QTy" required="required" class="form-control" value="<%=_QTY%>"></td>
</tr>
<tr>
<td>P</td>
<td><input type="text" name="_p" required="required" class="form-control" value="<%=_P%>"></td>
</tr>
<tr>
<td>W</td>
<td><input type="text" name="__w" required="required" class="form-control" value=<%=W %>></td>
</tr>
<tr>
<td>V</td>
<td><input type="text" name="__V" required="required" class="form-control" value="<%=_V%>"></td>
</tr>
<tr>
<td><input type="reset" value="Reset" class="btn btn-info"></td>
<td><input type="submit" name="update" value="Update" class="btn btn-primary"></td>
</tr>
</tbody>
</table>
</form>
</div>
</center>
<center>
<a href="jkpddReport.jsp">View BOQ</a>
</center>
</body>
</html>
-----------Весь стек трассировки-------
&низкотемпературный;%
26: попробуй
27: {
28: _ID = Integer.parseInt(request.getParameter("id"));
29: кон соединение = соединение с БД.параметр "createconnection"();
30: оператор stmt = con.createStatement();
31: ResultSet rst = stmt.executeQuery("select * from boq where id="+_ID+"");
Что я уже пробовал:
я уже пробовал это сделать:
_ID = Integer.parseInt(request.getParameter("id"));
Connection con = DBConnection.createConnection();
Statement stmt = con.createStatement();
ResultSet rst = stmt.executeQuery("select * from boq where id="+_ID+"");
if(rst.next())
{
_HsnCode = rst.getString("hsn_Code");
_ISHsnCodeConfirmed = rst.getString("is_hsnConfirmed");
GST_RATE = rst.getString("gst_rate");
IS_GST_RATECONFIRMED= rst.getString("is_gstRate_confirmed");
item_desc = rst.getString("item_Description");
UNIT = rst.getString("Unit");
_QTY = rst.getString("Qty");
_P = rst.getString("p");
W = rst.getString("w");
_V = rst.getString("v");
_ID = rst.getInt("id");
out.println(rst.getInt("id"));
даже это тоже не сработало.