What will be the output?class One{ final int a = 15;}class Two extends One{ final int a = 20;}public class Test extends Two{ final int a = 30; public static void main(String args[]){ Test t = new One(); System.out.print(t.a); }} 20 Compiler Error 15 30 None of these TRUE ANSWER : ? YOUR ANSWER : ?
The concept of multiple inheritance is implemented in Java byI. Extending two or more classes.II. Extending one class and implementing one or more interfaces.III. Implementing two or more interfaces. Only (III) Only (II) (I) and (II) Only (I) (II) and (III) TRUE ANSWER : ? YOUR ANSWER : ?
Which of the following is true?1. A class can extend more than one class.2. A class can extend only one class but many interfaces.3. An interface can extend many interfaces.4. An interface can implement many interfaces.5. A class can extend one class and implement many interfaces. 2 and 4 3 and 5 3 and 4 2 and 5 1 and 2 TRUE ANSWER : ? YOUR ANSWER : ?
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. } None of these Compilation fails due to an error on lines 9 Compilation fails due to an error on lines 5 Name B Name C TRUE ANSWER : ? YOUR ANSWER : ?
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); }} Class cast Exception at runtime. prints "Cattle eats hay" prints "Horse eats hay" None of these prints "Mammal eats food" TRUE ANSWER : ? YOUR ANSWER : ?
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(); }} Compilation fails. ClassCastException exception is thrown at runtime. "carcar" is printed. "vehiclecar" is printed. "vehiclebike" is printed. TRUE ANSWER : ? YOUR ANSWER : ?
What will be the output?class Parent{ public void method(){ System.out.println("Hi i am parent"); }}public class Child extends Parent{ protected void method(){ System.out.println("Hi i am Child"); } public static void main(String args[]){ Child child = new Child(); child.method(); }} Compile time error Compiles successfully and print Run Time error None of This Compiles successfully and print TRUE ANSWER : ? YOUR ANSWER : ?
What is the output of the following program code?abstract class C1{public C1(){ System.out.print(1); } } class C2 extends C1{ public C2(){ System.out.print(2); } } class C3 extends C2{ public C3(){ System.out.println(3); } } public class Test{ public static void main(String[] a){ new C3(); } } 23 12 321 123 TRUE ANSWER : ? YOUR ANSWER : ?
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); }} hello (String, Integer[]) Overridden: hello (String, Integer[]) None of these Compilation fails TRUE ANSWER : ? YOUR ANSWER : ?
Which is true? "X extends Y" is correct if and only if X is a class and Y is an interface "X extends Y" is correct if and only if X is an interface and Y is a class "X extends Y" is correct if X and Y are either both classes or both interfaces "X extends Y" is correct for all combinations of X and Y being classes and/or interfaces TRUE ANSWER : ? YOUR ANSWER : ?