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Tag: JVM internals

  • Java Tutorial Roadmap

    Introduction to Java

    Overview of Java

    Java is a high-level, object-oriented, platform-independent programming language widely used for building enterprise applications, web applications, mobile apps, and backend systems.

    Java vs C++ vs Python

    • Java: Platform-independent, OOP-focused, strong memory management
    • C++: High performance, low-level memory control
    • Python: Simple syntax, rapid development, scripting-friendly

    Java Platform and Execution

    • Just-In-Time (JIT) Compiler
    • Difference between JIT and JVM
    • Bytecode vs Machine Code
    • How Java achieves platform independence

    Java Basic Concepts

    Java Basic Syntax

    • Structure of a Java program
    • Writing a Hello World program

    Data Types in Java

    • Primitive data types
    • Object (reference) data types

    Identifiers

    • Java identifier naming rules

    Variables in Java

    • Variable declaration and initialization
    • Scope of variables

    Input and Output in Java

    Console Input

    • Taking user input in Java
    • Scanner class
    • Different ways to read input from the console

    Output in Java

    • Using System.out.println()
    • Formatted output using printf()

    Operators in Java

    Types of Operators

    • Unary operators
    • Assignment operators
    • Relational operators
    • Logical operators
    • Ternary operator

    Flow Control in Java

    Decision-Making Statements

    • if statement
    • if-else statement
    • if-else-if ladder

    Loops

    • while loop
    • do-while loop
    • for-each loop

    Control Statements

    • break statement
    • continue statement
    • return keyword

    Arrays in Java

    Arrays Overview

    • Declaring and initializing arrays

    Types of Arrays

    • One-dimensional arrays
    • Multidimensional arrays
    • Jagged arrays
    • Final arrays

    Arrays Utility Classes

    • Arrays class
    • reflect.Array
    • Difference between util.Arrays and reflect.Array

    Object-Oriented Programming (OOP) in Java

    Java Naming Conventions

    • Class, method, and variable naming rules

    Classes and Objects

    • Understanding classes and objects
    • Object class in Java
    • Singleton design pattern

    Constructors

    • Default and parameterized constructors
    • Copy constructor
    • Constructor overloading
    • Constructor chaining
    • Private constructors and singleton classes

    Inheritance in Java

    Inheritance Concepts

    • Inheritance and constructors
    • Types of inheritance
    • Interfaces and inheritance

    Multiple Inheritance

    • Achieved using interfaces

    Abstraction in Java

    Abstraction Concepts

    • Abstract classes
    • Abstract methods
    • Control abstraction

    Data Hiding vs Abstraction

    • Key differences

    Encapsulation in Java

    Encapsulation Concepts

    • Data hiding using access modifiers

    Abstraction vs Encapsulation

    • Key differences and use cases

    Polymorphism in Java

    Polymorphism Concepts

    • Compile-time polymorphism
    • Runtime polymorphism

    Dynamic Method Dispatch

    • Method overriding

    Inheritance vs Polymorphism

    • Conceptual differences

    Methods in Java

    Methods Overview

    • Defining and calling methods

    Method Overloading

    • Compile-time polymorphism

    Method Overriding

    • Runtime polymorphism

    Memory Management in Java

    Memory Allocation

    • Stack vs Heap memory

    JVM Memory Areas

    • Types of memory areas allocated by JVM

    Garbage Collection

    • Garbage collection basics
    • Types of JVM garbage collectors

    Memory Leaks

    • Causes and prevention

    Java Virtual Machine (JVM)

    JVM Stack Area

    • Stack frames and execution

    Wrapper Classes

    Wrapper Classes Overview

    • Character class
    • Byte, Short, Long, Float classes

    Keywords in Java

    Java Keywords

    • List of Java keywords

    Important Keywords

    • super
    • final
    • static
    • enum
    • transient
    • volatile

    final vs finally vs finalize

    • Differences and use cases

    Access Modifiers

    Types of Access Modifiers

    • Public
    • Protected
    • Package-private
    • Private

    Access vs Non-Access Modifiers

    • Key differences

    Inner Classes in Java

    Inner Class Concepts

    • Types of inner classes

    Packages in Java

    Package Basics

    • Creating packages

    Common Packages

    • java.util
    • java.lang
    • java.io

    Exception Handling in Java

    Exception Basics

    • Types of exceptions
    • Checked vs unchecked exceptions

    Exception Handling Mechanism

    • try, catch, finally
    • Flow control in exception handling

    throw and throws

    • Custom exception handling

    Advanced Exception Topics

    • User-defined exceptions
    • Chained exceptions

    Multithreading in Java

    Thread Basics

    • Lifecycle and states of a thread
    • Main thread

    Thread Creation

    • Thread class
    • Runnable interface

    Thread Management

    • Thread priority
    • Naming threads
    • start() method behavior

    Synchronization and Concurrency

    Thread Synchronization

    • Importance of synchronization
    • Method-level and block-level synchronization

    Locks and Concurrency

    • Lock framework vs synchronization
    • Atomic vs volatile vs synchronized

    Deadlocks

    • Deadlock concepts
    • Prevention and avoidance

    Advanced Locks

    • Lock vs monitor
    • ReentrantLock

    File Handling in Java

    File Handling Basics

    • File class
    • Creating files

    Reading Files

    • Different ways to read text files

    Writing Files

    • Writing data into files
    • FileWriter class

    File Operations

    • Deleting files
    • File permissions

    Advanced File Handling

    • FileDescriptor
    • RandomAccessFile