如何设置Intellij，这样当我打开一个类时，无论在什么目录下它都可以正常运行？

Question

I'm a Java beginner and came from JGrasp where I could simply open up a class anywhere and be able to run it without any problems. When I open a class in Intellij it says the configuration isn't correct. Is there a way to set up Intellij by default to automatically set up the SDK for everything to default and allow me to open up any class without setting up configuration for each one. I attached an image that shows the edit configuration popup for a directory I opened. I am aware how to set up a project from scratch but I'd like to be able to open up code from anywhere without too much hassle setting up SDKs and configurations every time.

Here is the code :

Answer 1

To be able to run a class, you first need that class to have a "psvm" ( public static void main , which can be easily generated for you by simply writing "psvm" when you're coding a new method in a class).

Once that's done, you head over to the left, in your project's folder-tree, right-click your class, and press the "Run" button.

The green arrow on top of the class' blue circle indicates that this class has a "psvm" and that you thus can "Run" it.

After having done this once, IntelliJ will remember that you have ran this class and the "Edit confirguration" dropdown should usually always allow you to select it. Once the class you want to Run from that dropdown is selected, you can simply press the green triangle next to it.

Answer 2

您应将源代码（即扩展名为.java的文件）放置到一个单独的目录（与已编译的类（即扩展名为.class的文件）​​），并将其设置为IDEA中的源根目录：右键单击哪个服务器作为根软件包目录，然后选择->标记为->源根。