Thread: Main method not found?

I copied this exactly from my book:

public class Block {
    int a, b, c;
    int volume;
 
    Block(int i, int j, int k){
        a=i;
        b=j;
        c=k;
        volume=a*b*c;        
    }
    boolean sameBlock(Block ob){
        return (ob.a==a)&(ob.b==b)&(ob.c==c);
    }
    boolean SameVol(Block ob){
        return (ob.volume==volume);
    }
}
 
    class PassOb{
    public static void main(String[] args) {
        Block ob1= new Block(10, 2, 5);
        Block ob2 = new Block(10, 2, 5);
        Block ob3 = new Block(4, 5, 5);
 
        System.out.println("ob1 same dimensions as ob2; " +
                        ob1.sameBlock(ob2));
        System.out.println("ob1 same dimensions as ob3; " +
                        ob1.sameBlock(ob3));
        System.out.println("ob1 same volume as ob3; " +
                            ob1.SameVol(ob3));
 
    }
 
}

but when I try to run it by pressing F6 I get an error message that reads:

Error: Main method not found in class block.Block, please define the main method as:
   public static void main(String[] args)
or a JavaFX application class must extend javafx.application.Application
C:\Users\owner\AppData\Local\NetBeans\Cache\8.2\executor-snippets\run.xml:53: Java returned: 1
BUILD FAILED (total time: 9 seconds)

.


Now I can get it to run correctly and produce the desired output by pressing Shift+F6, but I'm wondering why I'm getting an error message at all.

Yes, that's the right output. It comes out correctly when I press Shift+F6. I was just wondering why it gives me the error message about not having a main method when I try to run it using only F6. I have other saved projects that run correctly when I only press F6.

r u running PassOb class or Block class

--- Update ---

java polymorphism | method overloading | mehtod overriding