Core Java Complete Notes By Durga Sir Direct

In the vast ecosystem of Java learning resources, few names command as much respect and reverence in the Indian software community as . For over a decade, his teachings have been the stepping stone for thousands of software engineers who are now working in top-tier multinational companies.

Unlike standard textbooks (Herbert Schildt, Cay Horstmann), Durga Sir’s notes are . Key differentiators include: core java complete notes by durga sir

Type Size (Bytes) Range byte 1 -128 to 127 short 2 -32768 to 32767 int 4 -2^31 to 2^31 - 1 long 8 -2^63 to 2^63 - 1 Homogeneous element collection. Fixed in size. Objects created in heap memory. Index starts at 0. 2. Operators and Assignments Evaluation Order Operands evaluate left-to-right. Precedence determines operator execution. Key Operators : ++ , -- (Pre and Post). Arithmetic : + , - , * , / , % . String Concatenation : + operator overloaded. Relational : < , <= , > , >= . Equality : == , != (Compares references). Instanceof : Checks object type compatibility. Bitwise : & , | , ^ . Short-Circuit : && , || (Skips unnecessary evaluation). 3. Flow Control Selection Statements if-else : Executes blocks conditionally. switch : Tests variable against multiple values. Switch allows byte , short , char , int . Enums and Strings allowed since Java 5 and 7. Iterative Statements while : Loops while condition is true. do-while : Executes at least once. for : Best for known iteration counts. for-each : Traverses arrays and collections easily. Transfer Statements break : Exits current loop or switch. continue : Skips current loop iteration. 4. Object-Oriented Programming (OOPs) Data Hiding Internal data stays hidden from outside. Achieved using private modifiers. Abstraction Hides internal implementation details. Highlights essential features to users. Encapsulation Data hiding + Abstraction. Grouping data and methods together. Achieved via getter/setter methods. Inheritance Is-A relationship. Code reusability feature. Uses extends keyword. Multiple inheritance not supported via classes. Polymorphism One name, multiple forms. Compile-time : Method overloading. Runtime : Method overriding. In the vast ecosystem of Java learning resources,

In the vast ecosystem of Java learning resources, few names command as much respect and reverence in the Indian software community as . For over a decade, his teachings have been the stepping stone for thousands of software engineers who are now working in top-tier multinational companies.

Unlike standard textbooks (Herbert Schildt, Cay Horstmann), Durga Sir’s notes are . Key differentiators include:

Type Size (Bytes) Range byte 1 -128 to 127 short 2 -32768 to 32767 int 4 -2^31 to 2^31 - 1 long 8 -2^63 to 2^63 - 1 Homogeneous element collection. Fixed in size. Objects created in heap memory. Index starts at 0. 2. Operators and Assignments Evaluation Order Operands evaluate left-to-right. Precedence determines operator execution. Key Operators : ++ , -- (Pre and Post). Arithmetic : + , - , * , / , % . String Concatenation : + operator overloaded. Relational : < , <= , > , >= . Equality : == , != (Compares references). Instanceof : Checks object type compatibility. Bitwise : & , | , ^ . Short-Circuit : && , || (Skips unnecessary evaluation). 3. Flow Control Selection Statements if-else : Executes blocks conditionally. switch : Tests variable against multiple values. Switch allows byte , short , char , int . Enums and Strings allowed since Java 5 and 7. Iterative Statements while : Loops while condition is true. do-while : Executes at least once. for : Best for known iteration counts. for-each : Traverses arrays and collections easily. Transfer Statements break : Exits current loop or switch. continue : Skips current loop iteration. 4. Object-Oriented Programming (OOPs) Data Hiding Internal data stays hidden from outside. Achieved using private modifiers. Abstraction Hides internal implementation details. Highlights essential features to users. Encapsulation Data hiding + Abstraction. Grouping data and methods together. Achieved via getter/setter methods. Inheritance Is-A relationship. Code reusability feature. Uses extends keyword. Multiple inheritance not supported via classes. Polymorphism One name, multiple forms. Compile-time : Method overloading. Runtime : Method overriding.