True and False quetions
20. True or False: If a subclass constructor does not explicitly call a superclass constructor, Java will not call any of the superclass's constructors.
False
21. True or False: An object of a superclass can access members declared in a subclass.
False
True or False: A class may only implement one interface.
False
True or False: A component placed in a GridLayout manager's cell will not be resized to fill up any extra space in the cell.
False
True or False: A mutually exclusive relationship is automatically created among all JRadioButton components in the same container.
False
True or False: A subclass reference variable can reference an object of the superclass.
False
True or False: A superclass has a member with package access. A class that is outside the superclass's package but inherits from the superclass can access the member.
False
True or False: When a method is declared with the final modifier, it must be overridden in a subclass.
False
True or False: You can place multiple components inside a BorderLayout region.
False
True or False: You can place multiple components inside a GridLayout cell.
False
True or False: You normally add JCheckBox components to a ButtonGroup object.
False
12. True or False: A panel cannot be displayed by itself.
True
15. True or False: You can place multiple components inside a container governed by a FlowLayout manager.
True
16. True or False: You can place a panel inside a region governed by a BorderLayout manager.
True
19. True or False: In a subclass, a call to the superclass constructor can only be written in the subclass constructor.
True
20. True or False: You can write a class that extends the JPanel class.
True
True or False: A superclass reference variable can reference an object of a subclass that extends the superclass.
True
True or False: By default all members of an interface are public.
True
True or False: The superclass constructor always executes before the subclass constructor.
True
True or False: When a class contains an abstract method, the class cannot be instantiated.
True
Find the Error 1. The following statement is in a class that uses Swing components: import java.swing.*;
import javax.swing. *;
