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Why can't I run particular classes in Intellij? For instance, I have following classes in the same project, but I can't run all of them. How to fix that?

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Cœur
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Dreikäsehoch
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    Do they have a main method? If not, how could they be run? – JB Nizet Dec 10 '18 at 19:28
  • Afaik, the ones with the triangles have a runnable `main`. If they don't have a triangle, they must either not have a main, or the signature for the `main` is incorrect. We can't say without seeing them. – Carcigenicate Dec 10 '18 at 19:28

2 Answers2

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These classes have methods with the signature public static void main(String[]), the entry point for a Java program. Classes that don't have a method with this signature will (with some exceptions, i.e. JavaFX' Application) not be shown as runnable by IntelliJ.

Marv
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According to the documentation it denotes a:

Java class that contains declaration of the main() method.

If you want to run the program you will need to add a main()

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GBlodgett
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