Beginner quizzes – Java inheritance

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 Inheritance.

Quiz 1: Easy Java Inheritance

What happens when the following program is compiled and run?

public class MySuper {

	protected String s = "Charles";

	void method(){
		System.out.print(s);
	}
}

class MySub extends MySuper {

	String s = "Emma";

	MySub() {
		System.out.print(super.s);
	}
	void method(){
		System.out.print(s);
		super.method();
	}
	public static void main(String[] args){
		MySub mySub = new MySub();
		mySub.method();
	}
}

Select the correct answer.

a – This code does not compile.

b – The main method writes “Emma Charles” to the standard output.

c – The main method writes “Charles Emma” to the standard output.

d – The main method writes “Emma Emma Charles” to the standard output.

e – The main method writes “Charles Emma Charles” to the standard output.

f – The main method writes “Emma Charles Emma” to the standard output.

g – The main method writes “null” to the standard output.

h – The main method writes nothing to the standard output.

Quiz 2: Inheriting a super class in Java

What happens when the following program is compiled and run?

public class Super {

	int a = 1;

	Super() {
		a = 5;
	}
}

public class Sub extends Super {

	Sub(int a) {
		System.out.print("-a" + a + "-a" + super.a);
	}
	public static void main(String[] args){
		Sub sub = new Sub(2);
	}
}

Select the correct answer.

a – This code does not compile.

b – The main method writes “-a0-a0” to the standard output.

c – The main method writes “-a2-a1” to the standard output.

d – The main method writes “-a2-a5” to the standard output.

e – The main method writes “-a2-a1” to the standard output.

f – The main method writes nothing to the standard output.

Article: Java inheritance Quizzes: Beginner  Intermediate  Advanced

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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.

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