我正在使用play framework（2.8.19）创建一个java web应用程序。在创建注册页面时，我试图将输入从注册页面（scala.html）传递到控制器类，控制器类将输入保存到Postgres表。在这里，我在访问控制器类的输入字段时遇到了空指针异常。下面是注册页面、控制器类和我的路由文件的代码。

Routes.file

`POST /users/ controllers.Users.save(request: Request)`

registraion.scala.html

@(userFrom: Form[commons.Forms.User])
@()(implicit request: Http.Request)
<!--@(userFrom: Form[commons.Forms.User]) (implicit request: RequestHeader, messagesProvider: play.i18n.MessagesProvider)-->
@main("User form") {
    <h1>User form</h1>
    @helper.form(action = routes.Users.save()) {

    <form>
    <!-- <legend>User (@userFrom("name").value)</legend>-->
    <!-- <legend>User (userFrom("email"))</legend>-->
    <div class="form-group">
    <label for="name">Email address</label>
    <input type="text" class="form-control" id="name" name="name" placeholder="Name">
    </div>
    <div class="form-group">
    <label for="email">Email address</label>
    <input type="email" class="form-control" id="email" name="email" placeholder="Email">
    </div>
    <div class="form-group">
    <label for="password">Password</label>
    <input type="password" class="form-control" id="password" name="password" placeholder="Password">
    </div>
    <input type="submit" class="btn btn-primary" value="Save">
    <a class="btn" href="@routes.Authentication.login()">Cancel</a>
    </form>

    }
}

Users.java（Controller）

public class Users extends Controller {
    private IUserDao iuserDao;
    private final Form<Forms.User> formFactory;
    private final play.i18n.MessagesApi messagesApi;

    @Inject
    public Users(FormFactory formFactory, MessagesApi messagesApi) {
        this.formFactory = formFactory.form(Forms.User.class);
        this.messagesApi = messagesApi;
    }

    public Result save(Http.Request request) {
        Messages messages = this.messagesApi.preferred(request);
        System.out.println("calling here");
        System.out.println(request.getHeaders());
        Form<Forms.User> userForm = formFactory.bindFromRequest(request);

        if (userForm.hasErrors()) {
            return badRequest(registration.render(userForm));
        }

        Forms.User user = userForm.get(); 
        System.out.println(user.email); //** <====== Facing error in this line =====>**
        models.AppUser searchResult = (AppUser) iuserDao.findByEmail(user.email);
        if (searchResult != null) {
            return badRequest(registration.render(userForm));
        }

        iuserDao.create(user);
        return redirect(routes.Authentication.login());
    }
}

这里Form User类为

public class Forms {

    public static class User {
        public String name;
        public String email;
        public String password;
    }
}

错误的快照在这里。
ERROR