- Java - Home
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- JVM - Java Virtual Machine
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Java Operators
- Java - Operators
- Java - Arithmetic Operators
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Java Control Statements
- Java - Decision Making
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Object Oriented Programming
- Java - OOPs Concepts
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Java Built-in Classes
Java File Handling
- Java - Files
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Java Error & Exceptions
- Java - Exceptions
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Java Multithreading
- Java - Multithreading
- Java - Thread Life Cycle
- Java - Creating a Thread
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Java Synchronization
- Java - Synchronization
- Java - Block Synchronization
- Java - Static Synchronization
- Java - Inter-thread Communication
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- Java - Interrupting a Thread
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Java Networking
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- Java - URL Class
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Java Collections
Java Interfaces
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Java Data Structures
Java Collections Algorithms
Advanced Java
- Java - Command-Line Arguments
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- Java - Applet Basics
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- Java - Autoboxing and Unboxing
- Java - File Mismatch Method
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- Java - Multi-Release Jar Files
- Java - Private Interface Methods
- Java - Inner Class Diamond Operator
- Java - Multiresolution Image API
- Java - Collection Factory Methods
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- Java - Nashorn JavaScript
- Java - Optional Class
- Java - Method References
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- Java - Dynamic CDS archive
- Java - Z Garbage Collector (ZGC)
- Java - Null Pointer Exception
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- Java - Garbage Collection
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Java Miscellaneous
- Java - Recursion
- Java - Regular Expressions
- Java - Serialization
- Java - Strings
- Java - Process API Improvements
- Java - Stream API Improvements
- Java - Enhanced @Deprecated Annotation
- Java - CompletableFuture API Improvements
- Java - Streams
- Java - Datetime Api
- Java 8 - New Features
- Java 9 - New Features
- Java 10 - New Features
- Java 11 - New Features
- Java 12 - New Features
- Java 13 - New Features
- Java 14 - New Features
- Java 15 - New Features
- Java 16 - New Features
Java APIs & Frameworks
Java Class References
- Java - Scanner
- Java - Arrays
- Java - Strings
- Java - Date
- Java - ArrayList
- Java - Vector
- Java - Stack
- Java - PriorityQueue
- Java - LinkedList
- Java - ArrayDeque
- Java - HashMap
- Java - LinkedHashMap
- Java - WeakHashMap
- Java - EnumMap
- Java - TreeMap
- Java - IdentityHashMap
- Java - HashSet
- Java - EnumSet
- Java - LinkedHashSet
- Java - TreeSet
- Java - BitSet
- Java - Dictionary
- Java - Hashtable
- Java - Properties
- Java - Collection
- Java - Array
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
True, Static functions can be accessed via class name or via null reference.
Answer : D
Explaination
The double data type is represented by double-precision 64-bit IEEE 754 floating point.
Answer : A
Explaination
int variable has default value of 0 if defined as an instance/static variable.
Q 4 - Which of the following is true about public access modifier?
A - Variables, methods and constructors which are declared public can be accessed by any class.
Answer : A
Explaination
Public access modifier is used to make variables, methods and constructors accessible to any class.
Answer : B
Explaination
Inheritance represets IS-A relationship providing code reusablity . Consider the following statement: Circle is a Shape. Here Shape is super class and Circle is a child class extends the super class Shape.
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 overriding?
Answer : B
Explaination
If a subclass provides a specific implementation of a method that is already provided by its parent class, it is known as Method Overriding.
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 : B
Explaination
No, constructor cannot be inherited.
Q 10 - In which case, a program is expected to recover?
Answer : B
Explaination
A program is expected to recover if an exception occurs.