writefl.jsp

jsp数据库编程入门

<%!
   public int[] getNumber(String s)
   { 
     int[] mCount = new int[4];
     String strTemp = null;
     int i;
     java.io.RandomAccessFile rf = null;
     try {
           rf = new java.io.RandomAccessFile(s,"r");
         } catch(Exception e)
         {
           System.out.println(e);
           System.exit(0); 
         }
    for(i=0;i<4;i++)
    {
      try {
           strTemp = rf.readLine();
          } catch(Exception e) 
          {
             strTemp = "0";
          }
      if(strTemp==null) strTemp = "0";
      mCount[i] = new Integer(strTemp).intValue();
    }
    return mCount;
}

public void setNumber(String s,int[] x)
{
  try{
       java.io.PrintWriter pw = new java.io.PrintWriter(new java.io.FileOutputStream(s));
       for (int i=0;i<4;i++)
       {
         pw.println(x[i]+"");
       }
       pw.close();
     }catch(Exception e) 
     {
       System.out.println("Write file error:"+e.getMessage());
     }
}
%>

<%
   String tmp = null;
   int choice = -1;
   int[] count = new int[4];  
   tmp = request.getParameter("choice");
   if (tmp==null)
   {}
   else
   {
     choice = new Integer(tmp).intValue();
   }
   String s = request.getRealPath("count.txt");
   if (choice>=0)
   {
      count = getNumber(s);
      count[choice]++;
      setNumber(s,count);
   }
   response.sendRedirect("vote.jsp");
%>