Core Java From Scratch to Expert level

Learn how static members belong to the class and have a single shared copy, while non static members belong to each object, requiring object creation to access them.

Explore Java variable types: static, instance, local, and reference, covering scope, initialization rules, default values, and how to access static members with or without the class name.

Explore continuation of types of variables in Java, including local, static, and non-static concepts, with emphasis on initialization, scope, and access patterns in class design.

Explore Java data types and type casting, including upcasting and explicit downcasting, with examples of int, long, byte, and float conversions, default values, and memory considerations.

Master unary operators in Java, including post and pre increment and decrement, with examples that reveal how left- and right-hand side evaluations affect results.

Explore how to design and use methods in Java, emphasizing the call-and-return execution flow: object creation, entering tests, printing outputs, and returning control to the caller.

Learn the rules for designing Java methods: how the return keyword transfers control to the caller, when to return with or without a value, and how return types must match.

Understand that constructors share the class name and run when objects are created, returning to main afterward. Explore overloading constructors by argument count and type, with variables scoped to each constructor.

Explore how constructors work in Java, including object creation, the rule that constructors do not return a value, and how they differ from methods.

Explain how instance initialization blocks and static initialization blocks work in Java, their execution order relative to constructors and main, and how they initialize instance and static variables.

Learn the execution flow of a Java program by exploring SIB, I.B., and constructors, including how multiple blocks execute in sequence and how object creation affects output.

Learn how the this keyword points to the current object, lets you access static and non-static members, and enables constructor calls.

Explore the super keyword for accessing superclass members in inheritance, with rules: super must be first, not allowed with this in static context, and parent constructors may auto-insert super().