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Java Syntax and Structure

Introduction​

Understanding the basic syntax and structure of Java is essential for writing effective Java programs. This guide covers the fundamental elements of Java syntax and how to structure a Java program.

Basic Syntax​

Hello World Example​

The simplest Java program is a "Hello, World!" application. Here's what it looks like:

public class HelloWorld {
    public static void main(String[] args) {
        System.out.println("Hello, World!");
    }
}

Explanation​

  • Class Declaration: Every Java program must have at least one class definition. The class name should match the filename. In this case, HelloWorld is the class name.
  • Main Method: The main method is the entry point of any Java application. It is always written as public static void main(String[] args).
  • Statements: Each statement ends with a semicolon (;). The System.out.println method prints the specified message to the console.

Comments​

Comments are used to explain code and are ignored by the compiler.

  • Single-line comments start with //.
// This is a single-line comment
  • Multi-line comments are enclosed in /* ... */.
/*
 This is a multi-line comment
 that spans multiple lines.
 */