can anyone analyze this output? 1. abstract class Furniture { abstract void prnt

Question

can anyone analyze this output?

1.

abstract class Furniture {
abstract void prnt();}
class Recliner extends Furniture {
void prnt() { System.out.println("I'm a recliner");}
}
class LaZBoy extends Recliner {
void prnt() { System.out.println("I'm a lazboy");}
}
public class furnitureTest2 {
public static void main(String[] args) {
Furniture [] A = { new Recliner(), new Recliner(), new LaZBoy()};
for (int i=0; i<3; ++i)
A[i].prnt();
}
}

output

I'm a recliner
I'm a recliner
I'm a lazboy

2.

class A { int x = 1; }
class B extends A { }
class C extends B { int x = 2;}
public class classTest {
public static void main(String[] args) {
A w = new A(); System.out.println(w.x);
B u = new B(); System.out.println(u.x);
C v = new C(); System.out.println(v.x);
A [] a = { new A(), new B(), new C()};
for (int i=0; i<3; ++i)
System.out.println(a[i].x);
}
}

output :

1
1
2
1
1
1

Explanation / Answer

1)

when Array Furniture is initialized in main method

Furniture [] A = { new Recliner(), new Recliner(), new LaZBoy()};

A[0] holds reference of Recliner()

A[1] holds reference of Recliner()

and A[2] holds reference of LaZBoy()

Hence, when

for (int i=0; i<3; ++i)

A[i].prnt();

in implemented,

prnt() method of Recliner() is called on i = 0 and 1,

and prnt() method of LaZBoy() on i = 2;

Output:

I'm a recliner

I'm a recliner

I'm a lazboy

2)

A w = new A();

// variable x of class A is fetched and printed out

System.out.println(w.x);

// output: 1

B u = new B();

// variable x of class B is fetched and printed out,

since class B extends class A, it takes value of x from A

System.out.println(u.x);

// output: 1

C v = new C();

// variable x of class C is fetched and printed out

System.out.println(v.x);

// output: 2

A [] a = { new A(), new B(), new C()};

A[0] holds reference of class A() => A a = new A();

A[1] holds reference of class B() => A a = new B();

and A[2] holds reference of class C() => A a = new C();

Since object is of class A reference to C, when for loop is implement, value of x is printed out for class A only

output:

1

1

1

Final output:

1

1

2

1

1

1

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