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Socket (TCP & UDP) communication in Java

Socket communication in Java enables communication between two endpoints over a network. There are two main types of sockets: TCP sockets and UDP sockets. Let's explain both types with examples: TCP Socket Communication: 1. **Server Side**:    - The server creates a `ServerSocket` object to listen for incoming connections on a specific port.    - When a client connects, the server accepts the connection and creates a `Socket` object to communicate with the client.    - The server reads from and writes to the socket's input and output streams to communicate with the client. import java.io.*; import java.net.*; public class TCPServer {     public static void main(String[] args) throws IOException {         ServerSocket serverSocket = new ServerSocket(12345);         System.out.println("Server started. Waiting for client...");         Socket clientSocket = serverSocket.accept();         System.out.println("Client connected.");         BufferedReader in = new Bu

The @Override annotation

The `@Override` annotation is used in Java to indicate that a method in a subclass is overriding a method with the same signature in its superclass. It is not mandatory to use `@Override`, but it helps in detecting errors during compilation if the method signature does not match any method in the superclass. Here are some key points about `@Override`: 1. Purpose: It provides compile-time checking that a method is indeed overriding a method from a superclass. If there is a mismatch in the method signature (e.g., misspelling of method name, incorrect parameters), the compiler will generate an error. 2. Usage: `@Override` is placed immediately before the method declaration in the subclass that is intended to override a method in the superclass. 3. Compatibility: `@Override` annotation was introduced in Java 5. It can only be used with methods that are overriding a superclass method. If a method is not overriding a superclass method, using `@Override` will result in a compilation error.

Getter and setter methods

Getter and setter methods, also known as accessor and mutator methods, are used to retrieve and modify the values of private variables (fields) in a class. They provide controlled access to the class attributes, allowing encapsulation and maintaining data integrity. Here's an example demonstrating getter and setter methods in Java: public class Person {     private String name;     private int age;     // Getter method for the name attribute     public String getName() {         return name;     }     // Setter method for the name attribute     public void setName(String name) {         this.name = name;     }     // Getter method for the age attribute     public int getAge() {         return age;     }     // Setter method for the age attribute     public void setAge(int age) {         if (age >= 0 && age <= 120) { // Validate age             this.age = age;         } else {             System.out.println("Invalid age! Age should be between 0 and 120.");  

Just-In-Time (JIT) Compiler

The Java Virtual Machine (JVM) relies on the Just-In-Time (JIT) compilation to improve the runtime performance of Java programs. However, theoretically, it is possible to run Java programs without JIT compilation. In practice, running Java programs without JIT compilation is not a common scenario, and it would impact the performance of the Java applications. Here's how it works: Without JIT Compilation: In the absence of JIT compilation, the JVM would interpret the bytecode directly. Interpretation involves reading the bytecode line by line and executing the corresponding native instructions. This approach tends to be slower compared to executing native machine code directly. With JIT Compilation: JIT compilation converts bytecode into native machine code just before execution. The generated native machine code is specific to the underlying hardware. This allows the program to execute more efficiently, as it is no longer interpreted line by line. Advantages of JIT Compilation: Impr

Java Compilation Process

 The Java compilation process involves several steps, known as the Java compilation and execution lifecycle. Here's an overview: 1. Writing Java Source Code (HelloWorld.java): // HelloWorld.java public class HelloWorld {     public static void main(String[] args) {         System.out.println("Hello, World!");     } } Programmers write Java code using a text editor or an integrated development environment (IDE). The code is typically saved in a file with a .java extension. This file contains the human-readable Java source code. 2. Compilation (Java Compiler - javac): $ javac HelloWorld.java The Java source code is compiled by the Java Compiler (javac). During compilation, the compiler performs several tasks: Syntax Checking: Ensures that the code follows the correct syntax defined by the Java language. Semantic Analysis: Checks for semantic errors, ensuring that the code makes sense in the context of the Java language. Bytecode Generation: Converts the Java source code

C Program Compilation Steps

The compilation process of a C program involves several stages, from the source code written in the hello.c file to the creation of an executable file that can be loaded and executed by the operating system. Here is a simplified overview of the compilation process: Source Code (hello.c): The process begins with a programmer writing the source code in the C programming language. The source code is usually saved in a file with a .c extension, such as hello.c. Preprocessing: The preprocessor (cpp) is the first stage of compilation. It handles directives, such as #include and #define, and expands them. The result is a modified version of the source code, often referred to as the "preprocessed code." Compilation: The compiler (gcc) takes the preprocessed code and translates it into assembly code specific to the target platform. The output is stored in an assembly code file. Assembly: The assembler (as) takes the assembly code and converts it into machine code in the form of reloca

The history of computer programming languages

The history of computer programming languages is a fascinating journey that spans several decades. Here's a brief overview of key milestones in the evolution of programming languages: 1. Machine Code and Assembly Language (1940s): In the early days of computing, programmers worked directly with machine code, the binary language understood by computers. Assembly language, a low-level programming language using mnemonic codes, was introduced to make programming more human-readable. 2. Fortran (1957): Developed by IBM, Fortran (short for Formula Translation) was the first high-level programming language. Designed for scientific and engineering calculations, Fortran introduced the concept of a compiler, translating high-level code into machine code. 3. Lisp (1958): Developed by John McCarthy, Lisp (short for List Processing) was one of the earliest high-level languages designed for symbolic reasoning and artificial intelligence research. Known for its unique approach to code as data an

Configuring Java with Visual Studio Code

Configuring Java with Visual Studio Code involves installing the necessary extensions and setting up your Java development environment. Here are step-by-step instructions to configure Java with Visual Studio Code: Prerequisites: 1. Java Development Kit (JDK):    - Ensure that you have the Java Development Kit (JDK) installed on your system. You can download it from the official Oracle website or use OpenJDK. 2. Visual Studio Code:    - Download and install Visual Studio Code from the official website: [Visual Studio Code](https://code.visualstudio.com/) Configuration Steps: 1. Install the Java Extension Pack:    - Open Visual Studio Code.    - Go to the Extensions view by clicking on the Extensions icon in the Activity Bar on the side of the window or using the shortcut `Ctrl+Shift+X`.    - Search for "Java Extension Pack" in the Extensions marketplace(Microsoft Ownership).     - Install the extension pack. This pack includes various extensions for Java development. 2. Config