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.
Answer : A
Explaination
True, Static functions can be accessed via class name or via null reference.
Answer : A
Explaination
True, an empty .java file is a valid source file.
Answer : B
Explaination
float variable has default value of 0.0f if defined as an instance/static variable.
Answer : B
Explaination
boolean variable has default value of false if defined as an instance/static variable.
Q 5 - What is an immutable object?
A - An immutable object can be changed once it is created.
B - An immutable object can't be changed once it is created.
C - An immutable object is an instance of an abstract class.
Answer : B
Explaination
An immutable object can't be changed once it is created. String objects are immutable.
Q 6 - What is Set Interface?
A - Set is a collection of element which contains elements along with their key.
B - Set is a collection of element which contains hashcode of elements.
C - Set is a collection of element which cannot contain duplicate elements.
D - Set is a collection of element which can contain duplicate elements.
Answer : C
Explaination
Set is a collection of element which cannot contain duplicate elements. The Set interface contains only methods inherited from Collection and adds the restriction that duplicate elements are prohibited.
Q 7 - Static binding uses which information for binding?
Answer : A
Explaination
Static binding uses type information for binding.
Q 8 - What happens when thread's sleep() method is called?
A - Thread returns to the ready state.
Answer : B
Explaination
When a task invokes its sleep() method, it returns to the waiting state.
Q 9 - Which arithmetic operations can result in the throwing of an ArithmeticException?
Answer : A
Explaination
Integer / and % can result in the throwing of an ArithmeticException.
Q 10 - This is the parent of Error and Exception classes.
Answer : A
Explaination
Throwable is the parent of both Error and Exception class.
