- Java - Home
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- JVM - Java Virtual Machine
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- Java - Data Types
- Java - Type Casting
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Java Operators
- Java - Operators
- Java - Arithmetic Operators
- Java - Assignment Operators
- Java - Relational Operators
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- Java Operator Precedence & Associativity
- Java - Unary Operators
Java Control Statements
- Java - Decision Making
- Java - If Else Statement
- Java - Switch Statement
- Java - Loop Control
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- Java - While Loop
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Object Oriented Programming
- Java - OOPs Concepts
- Java - Object & Classes
- Java - Class Attributes
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- Java - Methods
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- Java - Constructors
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- Java - Inheritance
- Java - Aggregation
- Java - Polymorphism
- Java - Overriding
- Java - Method Overloading
- Java - Dynamic Binding
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- Java - Instance Initializer Block
- Java - Abstraction
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- Java - Enum Constructor
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Java Built-in Classes
- Java - Number
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Java File Handling
- Java - Files
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Java Error & Exceptions
- Java - Exceptions
- Java - try-catch Block
- Java - try-with-resources
- Java - Multi-catch Block
- Java - Nested try Block
- Java - Finally Block
- Java - throw Exception
- Java - Exception Propagation
- Java - Built-in Exceptions
- Java - Custom Exception
- Java - Chained Exception
Java Multithreading
- Java - Multithreading
- Java - Thread Life Cycle
- Java - Creating a Thread
- Java - Starting a Thread
- Java - Joining Threads
- Java - Naming Thread
- Java - Thread Scheduler
- Java - Thread Pools
- Java - Main Thread
- Java - Thread Priority
- Java - Daemon Threads
- Java - Thread Group
- Java - Shutdown Hook
Java Synchronization
- Java - Synchronization
- Java - Block Synchronization
- Java - Static Synchronization
- Java - Inter-thread Communication
- Java - Thread Deadlock
- Java - Interrupting a Thread
- Java - Thread Control
- Java - Reentrant Monitor
Java Networking
- Java - Networking
- Java - Socket Programming
- Java - URL Processing
- Java - URL Class
- Java - URLConnection Class
- Java - HttpURLConnection Class
- Java - Socket Class
- Java - Generics
Java Collections
Java Interfaces
- Java - List Interface
- Java - Queue Interface
- Java - Map Interface
- Java - SortedMap Interface
- Java - Set Interface
- Java - SortedSet Interface
Java Data Structures
Java Collections Algorithms
Advanced Java
- Java - Command-Line Arguments
- Java - Lambda Expressions
- Java - Sending Email
- Java - Applet Basics
- Java - Javadoc Comments
- Java - Autoboxing and Unboxing
- Java - File Mismatch Method
- Java - REPL (JShell)
- Java - Multi-Release Jar Files
- Java - Private Interface Methods
- Java - Inner Class Diamond Operator
- Java - Multiresolution Image API
- Java - Collection Factory Methods
- Java - Module System
- Java - Nashorn JavaScript
- Java - Optional Class
- Java - Method References
- Java - Functional Interfaces
- Java - Default Methods
- Java - Base64 Encode Decode
- Java - Switch Expressions
- Java - Teeing Collectors
- Java - Microbenchmark
- Java - Text Blocks
- Java - Dynamic CDS archive
- Java - Z Garbage Collector (ZGC)
- Java - Null Pointer Exception
- Java - Packaging Tools
- Java - Sealed Classes
- Java - Record Classes
- Java - Hidden Classes
- Java - Pattern Matching
- Java - Compact Number Formatting
- Java - Garbage Collection
- Java - JIT Compiler
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 - Marker Interface
- 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
The byte data type is represented by an 8-bit signed two's complement integer.
Minimum value: -128
Maximum value: 127
Answer : D
Explaination
The double data type is represented by double-precision 64-bit IEEE 754 floating point.
Answer : A
Explaination
Byte variable has default value of 0 if defined as an instance/static variable.
Q 4 - Which of the following is true about protected access modifier?
A - Variables, methods and constructors which are declared protected can be accessed by any class.
Answer : B
Explaination
Variables, methods, and constructors which are declared protected can be accessed by any class lying in the same package.
Q 5 - What is local variable?
A - Variables defined inside methods, constructors or blocks are called local variables.
B - Variables defined outside methods, constructors or blocks are called local variables.
C - Static variables defined outside methods, constructors or blocks are called local variables.
Answer : A
Explaination
Variables defined inside methods, constructors or blocks are called local variables. The variable will be declared and initialized within the method and it will be destroyed when the method has completed.
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 - Method Overloading is an example of
Answer : A
Explaination
Method Overloading is example of static binding.
Q 8 - What invokes a thread's run() method?
A - JVM invokes the thread's run() method when the thread is initially executed.
B - Main application running the thread.
Answer : A
Explaination
After a thread is started, via its start() method of the Thread class, the JVM invokes the thread's run() method when the thread is initially executed.
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.