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What is the output of running class C? class A {   public A() {     System.out.println(       "The default constructor of A is invoked");   } } class B extends A {   public B() {     System.out.println(       "The default constructor of B is invoked");   } } public class C  {   public static void main(String[] args) {     B b = new B();   } } Group of answer choicesNothing displayed"The default constructor of B is invoked""The default constructor of A is invoked" followed by "The default constructor of B is invoked""The default constructor of B is invoked" followed by "The default constructor of A is invoked""The default constructor of A is invoked"

Question

What is the output of running class C? class A {   public A() {     System.out.println(       "The default constructor of A is invoked");   } } class B extends A {   public B() {     System.out.println(       "The default constructor of B is invoked");   } } public class C  {   public static void main(String[] args) {     B b = new B();   } } Group of answer choicesNothing displayed"The default constructor of B is invoked""The default constructor of A is invoked" followed by "The default constructor of B is invoked""The default constructor of B is invoked" followed by "The default constructor of A is invoked""The default constructor of A is invoked"

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Solution 1

The output of running class C will be "The default constructor of A is invoked" followed by "The default constructor of B is invoked".

Here's why:

When you create an object of class B using new B(), the Java Virtual Machine (JVM) first calls the constructor of class B. However, because B is a subclass of A, before executing the B constructor, it calls the constructor of class A (the superclass).

So, the constructor of class A is invoked first, printing "The default constructor of A is invoked". After that, the constructor of class B is invoked, printing "The default constructor of B is invoked".

Therefore, the output will be:

The default constructor of A is invoked
The default constructor of B is invoked

This problem has been solved

Solution 2

The output of running class C will be "The default constructor of A is invoked" followed by "The default constructor of B is invoked".

Here's why:

  1. When you create an instance of class B with "new B()", the Java Virtual Machine (JVM) first calls the constructor of class B.

  2. However, because B is a subclass of A, before executing the B constructor, it first calls the constructor of the superclass A. This is why "The default constructor of A is invoked" is printed first.

  3. After the A constructor has finished, the JVM then executes the rest of the B constructor, printing "The default constructor of B is invoked".

So, the constructors are called in the order from the top of the inheritance tree (superclasses) down (subclasses).

This problem has been solved

Similar Questions

What is the output of running class C?  _____  A. "The default constructor of B is invoked"B. "The default constructor of A is invoked" followded by "The default constructor of B is invoked"C. "The default constructor of B is invoked" followed by "The default constructor of A is invoked"D. "The default constructor of A is invoked"

Analyze the following code carefully. Please select all that apply. public class Test {   public static void main(String[] args) {     A a = new A();     a.print();   } } class A {   String s;   A(String s) {     this.s = s;   }   void print() {     System.out.println(s);   } } Group of answer choicesThe program has a compile error because class A is not a public class.The program has a compile error because class A does not have a default constructor.The program compiles and runs fine and prints nothing.The program would compile and run if you change A a = new A() to A a = new A("5").

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What will be the output of the following code?class A {    void method() {        System.out.println("Class A");    }}class B extends A {    void method() {        super.method();        System.out.println("Class B");    }}public class Main {    public static void main(String[] args) {        B obj = new B();        obj.method();    }}

What will be the output of the following Java program?class A { int i; void display() { System.out.println(i); }}class B extends A { int j; void display() { System.out.println(j); }}class inheritance_demo { public static void main(String args[]) { B obj = new B(); obj.i = 1; obj.j = 2; obj.display(); }}Options02Compilation Error1

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