What are the key features of Java?

Java is a popular programming language that offers a range of features and capabilities. Here are some of the key features of Java:

Object-Oriented Programming: Java is an object-oriented programming language, which means that it supports the creation of objects and classes, encapsulation of data and behavior, inheritance, and polymorphism.

Platform Independence: Java is platform-independent, meaning that Java code can be written once and run on any platform that supports a Java Virtual Machine (JVM), which is responsible for running Java code. This feature enables Java programs to run on any hardware and operating system without needing any changes to the code.

Automatic Memory Management: Java provides automatic memory management through a process called garbage collection. The JVM automatically manages the allocation and deallocation of memory, allowing developers to focus on writing code instead of managing memory.

Security: Java is designed with security in mind. It includes features such as a class loader, a bytecode verifier, and a security manager, which help to prevent malicious code from running on a system.

Multithreading: Java supports multithreading, allowing programs to perform multiple tasks simultaneously. This feature enables developers to write applications that can take advantage of modern multi-core processors.

Robust Standard Library: Java comes with a large standard library that provides a range of useful classes and methods, from basic I/O operations to advanced networking and database access.

Here’s an example Java program that demonstrates some of these features:

import java.util.Scanner;

public class Calculator {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
    
        System.out.print("Enter the first number: ");
        int num1 = scanner.nextInt();
    
        System.out.print("Enter the second number: ");
        int num2 = scanner.nextInt();
    
        int sum = num1 + num2;
        System.out.println("The sum is " + sum);
    }
}

This program uses Java’s built-in Scanner class to read input from the user. It then performs a simple calculation and prints the result to the console. Note how the program takes advantage of Java’s object-oriented features by creating an instance of the Scanner class, and how it uses Java’s automatic memory management by not having to worry about deallocating the memory used by the Scanner object.