Java Online Quiz
Following quiz provides Multiple Choice Questions (MCQs) related to Core Java. You will have to read all the given answers and click over the correct answer. If you are not sure about the answer then you can check the answer using Show Answer button. You can use Next Quiz button to check new set of questions in the 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)
Answer : C
Explaination
Correct syntax is public static void main(String[] args).
Answer : D
Explaination
The long data type is represented by 64-bit two's complement integer.
Minimum value: -263
Maximum value: 263-1
Answer : A
Explaination
int variable has default value of 0 if defined as an instance/static variable.
Answer : C
Explaination
Object variable has default value of null if defined as an instance/static variable.
Q 5 - What is an Interface?
A - An interface is a collection of abstract methods.
B - Interface is an abstract class.
Answer : C
Explaination
An interface is a collection of abstract methods. A class implements an interface, thereby inheriting the abstract methods of the interface.
Answer : B
Explaination
No, this is not possible.
Q 7 - What is function overloading?
A - Methods with same name but different parameters.
B - Methods with same name but different return types.
C - Methods with same name, same parameter types but different parameter names.
Answer : A
Explaination
If a class has multiple functions by same name but different parameters, it is known as Method Overloading.
Q 8 - Does garbage collection guarantee that a program will not run out of memory?
Answer : B
Explaination
Garbage collection does not guarantee that a program will not run out of memory. It is possible for programs to use up memory resources faster than they are garbage collected. It is also possible for programs to create objects that are not subject to garbage collection.
Q 9 - What will happen if static modifier is removed from the signature of the main method?
B - RunTime Error: NoSuchMethodError.
C - Program will compile and run without any output.
D - Program will compile and run to show the required output.
Answer : B
Explaination
Program throws "NoSuchMethodError" error at runtime.
Answer : D
Explaination
All threads must implement the run() method.
