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Java Multithreading
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Java Networking
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Advanced Java
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Java Miscellaneous
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Java APIs & Frameworks
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Java Useful Resources
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
The byte data type is represented by an 8-bit signed two's complement integer.
Minimum value: -128
Maximum value: 127
Q 2 - What is the size of boolean variable?
Answer : B
Explaination
The boolean data type can take either true or false, but its "size" isn't precisely defined.
Answer : B
Explaination
float variable has default value of 0.0f if defined as an instance/static variable.
Q 4 - Which of the following is true about private access modifier?
Answer : A
Explaination
Private access modifier is used to restrict access to variables, methods and constructors to member of same class only.
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.
Answer : B
Explaination
No, this is not possible.
Q 7 - What is composition?
A - Composition is a data structure.
B - Composition is a way to create an object.
C - Holding the reference of the other class within some other class is known as composition.
Answer : C
Explaination
Holding the reference of the other class within some other class is known as composition. It represents a HAS-A relationship. For example, a Student has a Pen. Here Student class has Pen as its instance variable.
Q 8 - What is a transient variable?
A - A transient variable is a variable which is serialized during Serialization.
B - A transient variable is a variable that may not be serialized during Serialization.
C - A transient variable is a variable which is to be marked as serializable.
Answer : B
Explaination
A transient variable is a variable that may not be serialized during Serialization and which is initialized by its default value during de-serialization.
Answer : A
Explaination
Deletion in linked list is fast because it involves only updating the next pointer in the node before the deleted node and updating the previous pointer in the node after the deleted node.
Answer : A
Explaination
Postfix operators i.e () [] . is at the highest precedence.