JAVA Inheritence
Which is true?

"X extends Y" is correct for all combinations of X and Y being classes and/or interfaces
"X extends Y" is correct if and only if X is a class and Y is an interface
"X extends Y" is correct if X and Y are either both classes or both interfaces
"X extends Y" is correct if and only if X is an interface and Y is a class

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JAVA Inheritence
Determine output:class A{public void method1(){System.out.print("Class A method1");}}class B extends A{public void method2(){System.out.print("Class B method2");}}class C extends B{public void method2(){System.out.print("Class C method2");}public void method3(){System.out.print("Class C method3");}}public class Test{public static void main(String args[]){A a = new A();C c = new C();c.method2();a = c;a.method3();}}

Runtime exception
Compilation Error
Class C method2 Class C method3
Class B method2 Class C method3
None of these

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JAVA Inheritence
Determine output:class A{ public void printName(){ System.out.println("Name-A"); }}class B extends A{ public void printName(){ System.out.println("Name-B"); }}class C extends A{ public void printName(){ System.out.println("Name-C"); }}1. public class Test{2. public static void main (String[] args){3. B b = new B();4. C c = new C();5. b = c;6. newPrint(b);7. }8. public static void newPrint(A a){9. a.printName();10. }11. }

Compilation fails due to an error on lines 5
Name B
Compilation fails due to an error on lines 9
Name C
None of these

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JAVA Inheritence
What will be the result after compiling this code?class SuperClass{ public int doIt(String str, Integer... data)throws Exception{ String signature = "(String, Integer[])"; System.out.println(str + " " + signature); return 1; }}public class Test extends SuperClass{ public int doIt(String str, Integer... data){ String signature = "(String, Integer[])"; System.out.println("Overridden: " + str + " " +signature); return 0; } public static void main(String... args){ SuperClass sb = new Test(); sb.doIt("hello", 3); }}

Overridden: hello (String, Integer[])
hello (String, Integer[])
None of these
Compilation fails

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JAVA Inheritence
What is the result of compiling and running this program?class Mammal{ void eat(Mammal m){ System.out.println("Mammal eats food"); }}class Cattle extends Mammal{ void eat(Cattle c){ System.out.println("Cattle eats hay"); }}class Horse extends Cattle{ void eat(Horse h){ System.out.println("Horse eats hay"); }}public class Test{ public static void main(String[] args){ Mammal h = new Horse(); Cattle c = new Horse(); c.eat(h); }}

None of these
Class cast Exception at runtime.
prints "Horse eats hay"
prints "Mammal eats food"
prints "Cattle eats hay"

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JAVA Inheritence
What will be the result of compiling and executing the following program code?class Vehicle{ public void printSound(){ System.out.print("vehicle"); }}class Car extends Vehicle{ public void printSound(){ System.out.print("car"); }}class Bike extends Vehicle{ public void printSound(){ System.out.print("bike"); }}public class Test{ public static void main(String[] args){ Vehicle v = new Car(); Bike b = (Bike) v; v.printSound(); b.printSound(); }}

"carcar" is printed.
"vehiclebike" is printed.
"vehiclecar" is printed.
ClassCastException exception is thrown at runtime.
Compilation fails.

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