How should a minimal Java program look like? [duplicate]

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• “Error: Main method not found in class MyClass, please define the main method as…” 8 answers

I wrote the following code:

import java.awt.*;
import java.awt.event.*;

class Party {
    public void buildInvite() {
        Frame f = new Frame();
        Label l = new Label("Party at Tim's");
        Button b = new Button("You bet");
        Button c = new Button("Shoot me");
        Panel p = new Panel();
        p.add(l);
    } //more code here...
}

I keep getting the following error: Exception in thread "main" java.lang.NoSuchMethodError: main

I've tried to add an additional main (String[] args) to the code but I still get the same errors.

What additionally I should put in the code and where in the layout should it go?