数据库小问题
代码: 
  <%@   page   contentType= "text/html;charset=GB2312 "%>  
  <%@   page   import= "java.sql.* "%>  
  <html>  
  <body>  
  <% 
    Connection   con; 
    Statement   sql; 
    ResultSet   rs; 
    try{Class.forName( "sun.jdbc.odbc.JdbcOdbcDriver "); 
          } 
          catch(
ClassNotFoundException   e){}   
    con=DriverManager.getConnection( "jdbc:odbc:sun ", "sa ", " "); 
    sql=con.createStatement(); 
    rs=sql.executeQuery( "select   *   from   user "); 
    while(rs.next()) 
    { 
       out.print(rs.getString(1)); 
       out.print(rs.getString(2)); 
       out.print(rs.getString(3)); 
       } 
       con.close(); 
       } 
       catch(
SQLException   e1){} 
       %>  
        </body>  
        </html>  
 报错:  
org.apache.jasper.JasperException:   Unable   to   compile   class   for   JSP:        
 Stacktrace: 
 	org.apache.jasper.compiler.DefaultErrorHandler.javacError(DefaultErrorHandler.java:85) 
 	org.apache.jasper.compiler.ErrorDispatcher.javacError(ErrorDispatcher.java:330) 
 	org.apache.jasper.compiler.JDTCompiler.generateClass(JDTCompiler.java:415) 
 	org.apache.jasper.compiler.Compiler.compile(Compiler.java:308) 
 	org.apache.jasper.compiler.Compiler.compile(Compiler.java:286) 
 	org.apache.jasper.compiler.Compiler.compile(Compiler.java:273) 
 	org.apache.jasper.JspCompilationContext.compile(JspCompilationContext.java:566) 
 	org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:308) 
 	org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:320) 
 	org.apache.jasper.servlet.JspServlet.service(JspServlet.java:266) 
 	javax.servlet.http.HttpServlet.service(HttpServlet.java:803)     
 note   The   full   stack   trace   of   the   root   cause   is   available   in   the   Apache   Tomcat/6.0.10   logs.   
------解决方案--------------------try{Class.forName( "sun.jdbc.odbc.JdbcOdbcDriver "); 
    } 
    catch(Class
NotFoundException e){}     
 //这里缺了try了...或者整合到前面那个try catch块中去 
 try {   
  con=DriverManager.getConnection( "jdbc:odbc:sun ", "sa ", " "); 
  sql=con.createStatement(); 
  rs=sql.executeQuery( "select * from user "); 
  while(rs.next()) 
  { 
   out.print(rs.getString(1)); 
   out.print(rs.getString(2)); 
   out.print(rs.getString(3)); 
   } 
   con.close(); 
   } 
   catch(SQLException e1){} 
------解决方案--------------------  try{//try上也不行吗? 
  con=DriverManager.getConnection( "jdbc:odbc:sun ", "sa ", " "); 
  sql=con.createStatement(); 
  rs=sql.executeQuery( "select * from user "); 
  while(rs.next()) 
  { 
   out.print(rs.getString(1)); 
   out.print(rs.getString(2)); 
   out.pr