Key Concepts in Core Java: Object-Oriented Programming (OOP):

Classes and Objects: Core building blocks of Java programs. Inheritance: Mechanism to reuse code and create relationships between classes. Polymorphism: Ability to process objects differently based on their data type or class. Abstraction: Hiding implementation details and showing only essential features. Encapsulation: Keeping fields within a class private and providing access through public methods. Basic Syntax and Constructs:

Data Types: Primitive types (int, char, boolean) and reference types (objects). Control Statements: If-else, switch, loops (for, while), etc. Exception Handling: Try-catch blocks, throw, throws, and custom exceptions for error handling. Collections Framework:

Lists, Sets, Maps: Data structures like ArrayList, HashSet, and HashMap to store and manipulate groups of objects efficiently. Iterators: To traverse collections. Multithreading:

Thread Class and Runnable Interface: Creating and managing multiple threads to execute tasks concurrently. Synchronization: Ensuring thread safety when multiple threads interact with shared resources. Java Input/Output (I/O):

Streams: For reading from and writing to files, consoles, and other I/O sources. Serialization: Converting an object’s state into a byte stream to store or transmit. Memory Management:

Garbage Collection: Automatic memory management that reclaims memory from objects no longer in use. Heap and Stack: Memory areas used for dynamic memory allocation and method execution. JVM (Java Virtual Machine):

Platform Independence: Bytecode compiled by the Java compiler runs on any machine that has a JVM. ClassLoader: Loads classes dynamically at runtime. JIT Compiler: Optimizes bytecode into machine code for faster execution.