By Durga Sir //top\\ | Core Java Complete Notes

This article provides a comprehensive overview of the Core Java complete notes by

Focus on JVM: Pay extra attention to the sections on Garbage Collection and Class Loaders, as these are his specialties. core java complete notes by durga sir

Depth: Moving beyond basic syntax to explain internal workings. This article provides a comprehensive overview of the

• JVM, JRE, JDK: role of each component; compilation vs. interpretation; class file structure (magic number, constant pool).
• Java memory model: Heap, Stack, Method Area, PC registers, Native area.
• javac and java commands; basic project structure and classpath; module system (brief intro).
• Primitive types and default values table (byte, short, int, long, float, double, char, boolean).
• Key keywords: final, static, transient, volatile, synchronized, native, strictfp.

• 1D, 2D, and Jagged Arrays (arrays where each row has a different length).
• Anonymous arrays (e.g., new int[]10,20,30) and their use in method arguments.

5.4 Generics

• Type Safety: ArrayList<String> only accepts Strings. Compile-time safety.
• Wildcards: ? extends Number (Upper bound) vs ? super Integer (Lower bound). The PECS rule (Producer Extends, Consumer Super).

Final Mantra from Durga Sir: "Java is not just a programming language; it is a platform. To master Java, you must master the JVM." JVM, JRE, JDK: role of each component; compilation vs