Java: Interface Exercises 1

Name ________________________________________

Example

public class MyPanel extends JPanel implements ActionListener {
    public void actionPerformed(ActionEvent e) {
    }
}

Exercises

What is the output from these statements, given the MyPanel class as defined above? Note: Neither JPanel nor its ancestors (superclasses) implements ActionListener.

JPanel p    = new JPanel();
MyPanel myp = new MyPanel();
ActionListener al;

al  = myp;

System.out.println("1. " + (p   instanceof JPanel));
System.out.println("2. " + (myp instanceof JPanel));
System.out.println("3. " + (p   instanceof MyPanel));
System.out.println("4. " + (p   instanceof ActionListener));
System.out.println("5. " + (myp instanceof ActionListener));
System.out.println("6. " + (al  instanceof JPanel));
System.out.println("7. " + (al  instanceof MyPanel));