Learn JAVA MCQs
Prepare JAVA MCQs (Multiple choice Questions) for exam and job interviews.
Which of the following is not a valid method in the String class?
1) charAt()
2) substring()
3) toLower()
4) None of the above
Answer : toLower()
What is the default value of a reference variable in Java?
1) 0
2) null
3) undefined
4) None of the above
Answer : null
Which of the following is true about the default constructor in Java?
1) It is provided automatically if no constructor is defined.
2) It must be explicitly defined by the programmer.
3) It can have parameters.
4) None of the above
Answer : It is provided automatically if no constructor is defined.
What is the output of System.out.println(3 * 3 + 5 / 2);?
1) 9
2) 10
3) 10.5
4) None of the above
Answer : 10
Which of the following is true about the Object class in Java?
1) It is the parent class of all classes.
2) It defines the equals() method.
3) It defines the hashCode() method.
4) All of the above
Answer : All of the above
Which of the following is not a valid return type for a method in Java?
1) void
2) int
3) String
4) class
Answer : class
What is the output of System.out.println(10 % 3);?
1) 1
2) 3
3) 0
4) None of the above
Answer : 1
Which of the following is true about encapsulation in Java?
1) It is a way to restrict access to certain components.
2) It can be achieved using access modifiers.
3) Both 1 and 2
4) None of the above
Answer : Both 1 and 2
Which of the following is used to define constants in Java?
1) const
2) final
3) static
4) None of the above
Answer : final
Which of the following is not a valid loop in Java?
1) for
2) while
3) do-while
4) foreach
Answer : foreach