为什么下面代码在执行时会出错？？请大家指教！

<%@ page contentType="text/html;charset=GB2312"%>
<%@ page import="java.sql.*"%>

<%!
    String user;
    String password;
        Connection conn;
        PreparedStatement ps;
        ResultSet rs;
        String dbdriver="com.microsoft.jdbc.sqlserver.SQLServerDriver";
    String url="jdbc:microsoft:sqlserver://127.0.0.1:1433;DatabaseName=pet";
%>
<%
    request.setCharacterEncoding("GB2312");
    user=request.getParameter("user");
    password=request.getParameter("password");
    try
    {
                Class.forName(dbdriver).newInstance();
                conn=DriverManager.getConnection(url,"sa","123456");
                ps=conn.prepareStatement("insert into message (user,password) values(?,?)");
                ps.setString(1,user);
                ps.setString(2,password);
                rs=ps.executeQuery();
              while(rs.next())
              {
%>
                      <%=rs.getString(1)%><br>
<%    
                }
                      rs.close();
                      ps.close();
                      conn.close();
      }
      catch(Exception e)
    {
            out.println(e);
    }
%>
java.sql.SQLException: [Microsoft][SQLServer 2000 Driver for JDBC][SQLServer]在关键字 'user' 附近有语法错误。