帮我看看这段代码有什么问题？为什么提示An error occurred at line: 11 in the jsp file: /zixue-2.jsp

<%@ page contentType="text/html; charset=gb2312" language="java" import="java.sql.*" errorPage="" %>
<%@ page import="java.io."%>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=gb2312" />
<title>无标题文档</title>
</head><body bgcolor="#00FFFF"><font size=6>
<%!
  int number=0;
 File file=new File("count.txt");
synchronized void countPeople()
{
  if(!file.exists())
   {
     number++;
    try{
       file.createNewFile();
   FileOutputStream out=new FileOutputStream("count.txt");
   DataOutputStream dataOut=new DataOutputStream(out);
   dataOut.writeInt(number);
   out.close();
   dataOut.close();
   }
   catch(IOException ee){}
  }
else
{
try{ 
      FileInputStream in=new FileInputStream("count.txt");
  DataInputStream dataIn=new DataInputStream(in);
  number=dataIn.readInt();
  number++;
  in.close();
  dataIn.close();
  FileOutputStream out=new FileOutputStream("count.txt");
  DataOutputStream dataOut=new DataOutputStream(out);
  dataout.writeInt(number);
  out.close();
  dataOut.close();
 }
 catch(IOexception  ee){}
 }
} 
 %>
  <% 
  countPeople();
  %>
  <p>您是第<%=number%>个访问本站的用户。</p></font>
</body></html>