Passing a method as a argument to other method in other class

We need to remember one basic rule regarding accessing the static method in outer packages which is "Static methods should be accessed directly with class name"

If a class is accessible and if static method is accessible, i mean defined with correct access modifiers then that static method can be accessed anywhere within the project or ouside the project. See this example


public class ClassA {

public static void main(String[] args) {
display(); // calling without object
ClassA t = new ClassA();
t.show(); // calling using object
}

public static void display() {
System.out.println("Programming is amazing.");
}

public void show() {
System.out.println("Java is awesome.");
}
}

public class ClassB {
public static void main(String[] args) {
ClassA.display(); // calling without object
ClassA t = new ClassA();
t.show(); // calling using object
}
}