更新任务模型 - RuntimeException：DataSource用户是否为空？ [英] Update the Task model - RuntimeException: DataSource user is null?

问题描述

我今天开始学习Play框架，它非常好且易于学习。

I started learning Play framework today and it is very good and easy to learn.

我成功完成了网站，但我想对其进行一些修改。

I successfully completed the sample provided on their website, but I wanted to make some modifications to it.

我想知道是否可以更新特定任务的标签，所以我遵循以下方法

I wanted to see if could update the label of a particular task, so I followed the following approach

首先我添加了更新数据的路径

First I added a route to update the data

POST    /tasks/:id/update           controllers.Application.updateTask(id: Long)

然后我将以下代码添加到 index.scala.html file

Then I added the following code to index.scala.html file

 @form(routes.Application.updateTask(task.id)) {
                    <label class="contactLabel">Update note here:</label> 
 @inputText(taskForm("label")) <br />
                }

然后我将Application.java类修改为

Then I modified Application.java class to

public static Result updateTask(Long id) {
        Form<Task> taskForm = Form.form(Task.class).bindFromRequest();
        if (taskForm.hasErrors()) {
            return badRequest(views.html.index.render(Task.all(), taskForm));
        } else {
            Task.update(id, taskForm.get());
            return redirect(routes.Application.tasks());
        }
    }

最后在Task.java中我添加了这段代码

Finally in Task.java I added this code

public static void update(Long id, Task task) {
        find.ref(id).update(task.label);
    }

但是当我执行更新操作时，我收到此错误

But when I perform the update operation I get this error

[RuntimeException：DataSource用户为空？]

[RuntimeException: DataSource user is null?]

不用说我注释掉了

 db.default.driver=org.h2.Driver
 db.default.url="jdbc:h2:mem:play"
 ebean.default="models.*"

在application.conf中，因为我已经能够保存和删除数据;但我无法更新数据库中的数据，为什么会发生这种情况，之前有人试过这个，我该如何解决这个错误？

in application.conf since I am already able to save and delete data; but I cannot update the data in the database, why is this happening, did someone try this before, how can I solve this error?

推荐答案

任务模型上的更新（长期ID，任务任务）方法应如下所示：

Your update(Long id, Task task) method on Task model should be like below:

public static void update(Long id, Task task) {
    task.update(id); // updates this entity, by specifying the entity ID
}

因为你传递了任务变量作为更新数据，您不需要像任务对象的引用> find.ref（ID）。而且， update（）方法 play.db.ebean.Model class（带一个参数）需要ID为模型作为参数。

Because you passed task variable as updated data, you don't need to find reference of Task object like you do in find.ref(id). And moreover, update() method on play.db.ebean.Model class (with one parameter) needs ID of model as parameter.

希望这有助于解决您的问题.. :)

Hope this help solving your problem.. :)

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