将表单提交的数据，封装到一个类中，并用servlet获取数据

假设表单有以下字段：username、password、email

封装数据到类中：

public class User {
    private String username;
    private String password;
    private String email;

    public User(String username, String password, String email) {
        this.username = username;
        this.password = password;
        this.email = email;
    }

    // getter and setter methods
}

在Servlet中获取数据：

protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
    String username = request.getParameter("username");
    String password = request.getParameter("password");
    String email = request.getParameter("email");

    User user = new User(username, password, email);

    // do something with user object
}