jsp 访问数据库问题：出现 conn cannot be resolved

数据库连接文件：datalin.jsp<%@pagecontentType="text/html;charset=GB2312"language="java"import... 数据库连接文件：datalin.jsp
<%@ page contentType="text/html; charset=GB2312" language="java" import="java.sql.*" errorPage="" %>
<%
.....代码省略..........
Class.forName("org.gjt.mm.mysql.Driver").newInstance();
Connection conn =null;
conn=DriverManager.getConnection(url);
Statement stmt=conn.createStatement(ResultSet.TYPE_SCROLL_SENSITIVE,ResultSet.CONCUR_UPDATABLE);
%>

---------------------------------
取得数据文件：getdata.jsp
<%@ page contentType="text/html; charset=GB2312" language="java" import="java.sql.*" errorPage="" %>
<%@ page language="java"%>
<%@ include file="dataline.jsp"%>

.....代码省略..........

<%!
String getArealnfo(String postalCode){
String arealnfo=null;
String sql="select * from postalcode where code like ?";

try{
ResultSet rss=null;
PreparedStatement pstmt=conn.prepareStatement(sql);
// PreparedStatement pstmt=conn.prepareStatement(sql);
pstmt.setString(1,postalCode);
rss=pstmt.executeQuery();
if(rss.next())
{
arealnfo=rss.getString("area")+"|"+rss.getString("city");
}else{
rss.close();
pstmt.setString(1,postalCode.substring(0,4)+"00");
rss=pstmt.executeQuery();
if(rss.next())
{
arealnfo=rss.getString("area")+"|"+rss.getString("city");
}
}
}catch(SQLException e){
System.out.println(e.toString());
}finally{

}
return arealnfo;
}
%>

出现问题：
org.apache.jasper.JasperException: Unable to compile class for JSP:

An error occurred at line: 25 in the jsp file: /getdata.jsp
conn cannot be resolved
22:
23: try{
24: ResultSet rss=null;
25: PreparedStatement pstmt=conn.prepareStatement(sql);
26: // PreparedStatement pstmt=conn.prepareStatement(sql);
27: pstmt.setString(1,postalCode);
28: rss=pstmt.executeQuery();

Stacktrace:
org.apache.jasper.compiler.DefaultErrorHandler.javacError(DefaultErrorHandler.java:92)
org.apache.jasper.compiler.ErrorDispatcher.javacError(ErrorDispatcher.java:330)
org.apache.jasper.compiler.JDTCompiler.generateClass(JDTCompiler.java:423)
org.apache.jasper.compiler.Compiler.compile(Compiler.java:317)
org.apache.jasper.compiler.Compiler.compile(Compiler.java:295)
org.apache.jasper.compiler.Compiler.compile(Compiler.java:282)
org.apache.jasper.JspCompilationContext.compile(JspCompilationContext.java:586)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:317)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:342)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:267)
javax.servlet.http.HttpServlet.service(HttpServlet.java:717)

note The full stack trace of the root cause is available in the Apache Tomcat/6.0.18 logs.

老是出现 conn cannot be resolved 为什么？？？怎么处理？展开

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