if语句不返回try-catch（Web服务）中的值

Question

@WebMethod(operationName = "operation")
public String operation(@WebParam(name = "username") String username, @WebParam(name = "password") String password){ 
    String message = "";
    try {
        Connection connection;
        PreparedStatement ps;

        connection = DriverManager.getConnection("jdbc:mysql://localhost/banksystem", "root", "");
        ps = connection.prepareStatement("SELECT `username`,`password` FROM `banklogin` WHERE `username`=? AND `password`=?");
        ps.setString(1, username);
        ps.setString(2, password);
        ResultSet result = ps.executeQuery();

        if(result.next()){
          message =  "Login Successful!";
        }else{
          message =  "Login Failed!";

        }
    } catch (SQLException ex) {
        Logger.getLogger(login.class.getName()).log(Level.SEVERE, null, ex);
    }
    return message;
}
}

当我尝试创建通过Web服务使用数据库的登录系统时会发生这种情况。我需要检查登录用户名和密码表单数据库并授予登录权限。