Beginner quizzes – Java nested classes

The following Java exercise(s) are designed for beginner level programmers. If the level is too hard, then I recommend reading my article about this topic, which offers a theoretical explanation including more exercises. Read More: Java Nested And Inner Classes

nested-classes-green

Quiz 1: A simple inner class.

What happens when you try to compile and run the following program?

class Outer {

	private int x = 12;

	class Inner {
		int x = 4;
		public Inner() {
			this.x += 3;
		}
		private void methodA(int x){
			x = this.x;
			System.out.print("x" + x);
		}
	}
	public static void main(String[] args){
		Inner inner = new Outer().new Inner();
		inner.methodA(5);
	}
}

Select the correct answer.


Quiz 2: A simple class with a nested class

What is written to the standard output as the result of executing the following code?

public class Outer {

    private int a = 2;

    Outer(){
       a = 5;
    }
    class Nested {
        Nested() {
            System.out.print("-a"+a);
            a = 3;
        }
    }
    public static void main(String[] args) {
        Nested nested = new Outer().new Nested();
    }
}

Select the correct answer.




Sar Maroof is a professional software development teacher, gives master classes and publishes technical articles. He is also an expert software developer and worked for several big as well as small companies and later as a freelancer.

 Subscribe to Sar Maroof's RSS feeds!
 Mail this page to a friend!
 Bookmark this page!

Leave a Reply

Your email address will not be published. Required fields are marked *