21. Thread class is available in________________?
A. java.lang package
B. java.util package
C. java.awt package
D. java.io package
✅ The correct answer is option A.
Java concepts and its programming MCQs
22. The following fraction of code double STATIC = 2.5 ; System.out.println( STATIC ); ?
A. Prints 2.5
B. Raises an exception
C. Raises an error as STATIC is used as a variable which is a keyword
D. None of these
✅ The correct answer is option A.
23. Inheritance means ?
A. Sub class create object of super class
B. Sub class extends Base class
C. Sub class extends super class
D. All of the above
✅ The correct answer is option C.
24. In Java byte, short, int and long all of these are ____________?
A. signed
B. unsigned
C. Both of the above
D. None of these
✅ The correct answer is option A.
25. If method have same name as class name and method don’t have any return type then it is known as______________?
A. Constructor
B. Destructors
C. Variable
D. Object
✅ The correct answer is option A.
26. The smallest integer type is _____________ and its size is____________ bits?
A. short, 8
B. byte, 8
C. short, 16
D. short, 16
✅ The correct answer is option B.
27. Which method of the Applet class displays the result of applet code on screen ?
A. paint() method
B. main() method
C. run() method
D. drawString() method
✅ The correct answer is option A.
28. Runnable is_______________?
A. Interface
B. Class
C. Variable
D. Method
✅ The correct answer is option A.
29. Converting a primitive type data into its corresponding wrapper class object instance is called ________________?
A. boxing
B. wrapping
C. autoboxing
D. instantiation
✅ The correct answer is option C.
30. javah stands for ?
A. java dissasamebler
B. java header file
C. java interpreter
D. java compiler
✅ The correct answer is option B.