Java Online Quiz

Q 1 - What is correct syntax for main method of a java class?

A - public static int main(String[] args)

B - public int main(String[] args)

C - public static void main(String[] args)

D - None of the above.

Q 2 - Can we have two public classes in one java file?

A - True

B - False

Q 3 - What is the default value of double variable?

A - 0.0d

B - 0.0f

C - 0

D - not defined

Q 4 - What is polymorphism?

A - Polymorphism is a technique to define different objects of same type.

B - Polymorphism is the ability of an object to take on many forms.

C - Polymorphism is a technique to define different methods of same type.

D - None of the above.

Q 5 - What is local variable?

A - Variables defined inside methods, constructors or blocks are called local variables.

B - Variables defined outside methods, constructors or blocks are called local variables.

C - Static variables defined outside methods, constructors or blocks are called local variables.

D - None of the above.

Q 6 - What is TreeSet Interface?

A - It is a Set implemented when we want elements in a tree based order.

B - It is a Set implemented when we want elements in a sorted order.

C - It is a Set implemented when we want elements in a binary tree format.

D - It is a Set implemented when we want elements in a hiearchical order.

Q 7 - Dynamic binding uses which information for binding?

A - type.

B - object.

C - Both of the above.

D - None of the above.

Q 8 - What invokes a thread's run() method?

A - JVM invokes the thread's run() method when the thread is initially executed.

B - Main application running the thread.

C - start() method of the thread class.

D - None of the above.

Q 9 - Which arithmetic operations can result in the throwing of an ArithmeticException?

A - / , %

B - * , +

C - ! , -

D - >>, <<

Q 10 - Which of the following is Faster, StringBuilder or StringBuffer?

A - StringBuilder

B - StringBuffer

C - Both of the above.

D - none of the above.