Legacy class; fully synchronized; rejects null keys and null values. 8. Java Virtual Machine (JVM) Internals
A child class providing a specific implementation for a method declared in its parent class. Durga Sir highlights rule checks regarding return types, access modifiers, and exception handling during overriding. Encapsulation and Abstraction
String objects are immutable in Java. Compounding modifications creates unnecessary objects in memory. Use a mutable StringBuilder for intensive string manipulation in single-threaded environments. core java complete notes by durga sir top
HashSet : Uses a hash table; offers constant-time performance for basic operations.
This comprehensive guide serves as an exhaustive reference blueprint based on the famous Core Java curriculum taught by Durga Sir. It covers everything from basic syntax to advanced object-oriented design and JVM internals. 1. Introduction to Java and Language Fundamentals Legacy class; fully synchronized; rejects null keys and
┌────────────────┐ ┌──────────────────────┐ ┌───────────────────┐ │ Subsystems │────>│ Memory Areas │────>│ Execution Engine │ │ ClassLoader │ │ Method, Heap, Stack │ │ JIT, Garbage Coll │ └────────────────┘ └──────────────────────┘ └───────────────────┘ 1. ClassLoader Subsystem
Program to interfaces rather than concrete classes to keep your application components decoupled and flexible. Durga Sir highlights rule checks regarding return types,
Caused by application logic; program recovery is possible (e.g., IOException , NullPointerException ).
Arrays in Java are treated as internal objects. Durga Sir warns about common pitfalls like ArrayIndexOutOfBoundsException and clarifies the difference between declaring, instantiating, and initializing arrays. 2. Object-Oriented Programming (OOPs) Concepts
Encapsulation is the practice of hiding data components and binding them with data-manipulating methods.
Responsible for loading, linking, and initializing .class files using a delegation hierarchy algorithm (Bootstrap, Extension, and Application class loaders). Runtime Data Areas (Memory Management):