请帮忙看看下面的程序哪里错了,页面正常显示,但总连不上数据库.
 下面上按书名查询代码:
 byBookName.jsp

<%@ page contentType="text/html; charset=GB2312" %>
<%@ page import="java.sql.*" %>
<HTML>
<BODY>
<%  // 获取提交的书名
    String bookname=request.getParameter("bookname");
         if(bookname==null)
           {  bookname="";
           }
    byte b[]=bookname.getBytes("ISO-8859-1");
    bookname= new String(b);
    Connection con;
    Statement sql;
    ResultSet rs;
         try{ 
              Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");
            }
         catch(ClassNotFoundException e)
            {
               System.out.print("error"+e.toString());
             }
         try{ con=DriverManager.getConnection("jdbc:odbc:sissy","sissy","");
              sql=con.createStatement();
              String condition="SELECT * FROM book WHERE bookname = "+"'"+bookname+"'";
              rs=sql.executeQuery(condition);
              System.out.println("rs");
              out.print("<Table Border>");
                  out.print("<TR>");
                  out.print("<TH width=100>"+"图书编号");
                  out.print("<TH width=100>"+"书名");
                  out.print("<TH width=100>"+"作者");
                  out.print("<TH width=100>"+"出版社");
                  out.print("<TH width=100>"+"出版日期");
                  out.print("<TH width=100>"+"类别");
                  out.print("<TH width=100>"+"价格"); 
                  out.print("</TR>");
              while(rs.next())
                { out.print("<TR>");
                  out.print("<TD>"+rs.getString(1)+"</TD>");
                  out.print("<TD>"+rs.getString(2)+"</TD>");
                  out.print("<TD>"+rs.getString(3)+"</TD>");
                  out.print("<TD>"+rs.getString(4)+"</TD>");
                  out.print("<TD>"+rs.getString(5)+"</TD>");
                  out.print("<TD>"+rs.getString(6)+"</TD>");
                  out.print("<TD>"+rs.getString(7)+"</TD>");
                  out.print("</TR>");
                 }
               out.print("</Table>");
               con.close();
              }
           catch(SQLException e)
              {
                   System.out.print("error"+e.toString());
              }
%>
</BODY>
</HTML>