JAVA Interfaces and Abstract Classes
What will happen after compiling this program code?abstract class MyClass{ //line 1 private int a, b; public void call(int a, int b){ this.a = a; this.b = b; System.out.print(a+b); }}public class Test{ public static void main(String args[]){ MyClass m = new MyClass(); //line 2 m.call(12,25); }}

Successful run and print 37
Runtime error
Compilation error due to line 2
Compilation error due to line 1
None of these

ANSWER DOWNLOAD EXAMIANS APP

JAVA Interfaces and Abstract Classes
Which of the following statements regarding abstract classes are true?

A subclass of a non-abstract superclass can be abstract.
All of these
An abstract class can be extended.
An abstract class can be used as a data type.
A subclass can override a concrete method in a superclass to declare it abstract.

ANSWER DOWNLOAD EXAMIANS APP

JAVA Interfaces and Abstract Classes
What will be the output when the following program is compiled and executed?abstract class TestAbstract{ String my_name; String myName(){ my_name = "Examveda"; return my_name; } abstract void display();}public class Test extends TestAbstract{ void display(){ String n = myName(); System.out.print("My name is "+ n); } public static void main(String args[]){ Test t = new Test(); t.display(); }}

Program will compile and execute successfully and prints
Compilation error as class can not be declared as abstract.
Compilation error occurs as the abstract class TestAbstract contains a non-abstract method.
None of these
Program compiles but leads to runtime exception.

ANSWER DOWNLOAD EXAMIANS APP

JAVA Interfaces and Abstract Classes
Given the following piece of code:public class School{ public abstract double numberOfStudent();}which of the following statements is true?

Class School must be defined abstract.
The keywords public and abstract cannot be used together.
You must add a return statement in method numberOfStudent().
The method numberOfStudent() in class School must have a body.

ANSWER DOWNLOAD EXAMIANS APP
MORE MCQ ON JAVA Interfaces and Abstract Classes