Who can help me deal with the question?

Question

My JSP platform is JDK1.3+RESIN1.1.5,whern i write these code ,i found something wrong!
<%@ page contentType="text/html;charset=gb2312"%>
<%@ page info="database handler"%>
<%@ page import="java.lang.*"%>
<%@ page import="java.awt.*"%>
<%@ page import="com.caucho.sql.*"%>
<%@ page import="java.io.*"%>
<%@ page import="java.util.*"%>
<%@ page import="java.sql.*"%>
<%@ page import="javax.servlet.*"%>
<%@ page import="javax.servlet.http.*"%>
<%! String username;%>
<%! String password;%>
<%! String sql;%>
<%
Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");
String url="jdbc:odbc:jsptest";
Connection conn=DriverManager.getConnection(url,"sa","hulachen");
Statement stmt=conn.createStatement(ResultSet.TYPE_SCROLL_SENSITIVE,ResultSet.CONCUR_READ_ONLY);
String username=request.getParameter("username");
String password=request.getParameter("password");
sql="select * from tbl_accounts where username='"+username+"' and password='"+password+"'";
ResultSet rs=stmt.executeQuery(sql);
while (rs.next())
String name=rs.getString("username");
out.print(name);
if (name==null)
out.print("error");
else
out.print("welcome");
%>
whether the name is null or not ,it will print error,i don't know why,who can help me?Thanks!

Answer 1

I did the same as you said,but the same thing happened!
the code is:
while (rs.next())
String name=rs.getString("username");
out.print(name);
if (name==null)
out.print("True");
else
out.print("False");
If the name is null,it printed False,but if the name is nothing,it didn't print True,but nothing!