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Java Error & Exceptions
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Java Multithreading
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Java Synchronization
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Java Networking
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Advanced Java
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Java Miscellaneous
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- Java 14 - New Features
- Java 15 - New Features
- Java 16 - New Features
Java APIs & Frameworks
Java Class References
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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
Answer : A
Explaination
True, a java file can contain one public class and many other non-public classes.
Answer : B
Explaination
Short variable has default value of 0 if defined as an instance/static variable.
Q 4 - Which of the following stands true about default modifier of class members?
A - By default, variables, methods and constructors can be accessed by subclass only.
Answer : C
Explaination
By default, variables, methods and constructors can be accessed by any class lying in the same package.
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.
Q 6 - What is JIT compiler?
A - JIT improves the runtime performance of computer programs based on bytecode.
B - JIT is an application development framework.
C - JIT is an implementation of the Java Virtual Machine which executes Java programs.
Answer : A
Explaination
JIT, Just In-Time Compiler, improves the runtime performance of computer programs based on bytecode.
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 - 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.
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.
Q 10 - Which of the following is a thread safe?
Answer : B
Explaination
StringBuffer is thread safe.