Console

The Console class in Java (available in the java.io package) provides methods to access the character-based console device — typically, the text terminal from which the user runs the program. It’s useful for reading input and writing output in a secure and interactive way, especially for password input where echoing is disabled.

The Console class cannot be instantiated manually.You retrieve a Console object using:

Console console = System.console();Code language: JavaScript (javascript)

Commonly Used Methods

Simple Program: Basic Console Input

Mahesh wants to enter his name and age using the command-line console. LotusJavaPrince needs to securely read it and display it.

import java.io.Console;
import java.util.Arrays;

public class SecureLogin {
    public static void main(String[] args) {
        Console console = System.console();

        if (console == null) {
            System.out.println("No console available. Run from a terminal.");
            return;
        }

        String username = console.readLine("Enter username: ");
        char[] password = console.readPassword("Enter password: ");

        // Simulate check (in a real app, don't use plain text!)
        if (username.equals("Mahesh") && Arrays.equals(password, "lotus123".toCharArray())) {
            console.printf("Login successful!\n");
        } else {
            console.printf("Invalid credentials.\n");
        }

        // Always clear password from memory
        Arrays.fill(password, ' ');
    }
}

Output

Enter username: Mahesh
Enter password: 
Login successful!

The Console class is ideal for interactive applications requiring user input via terminal.

• It enhances security by allowing password input with echo suppression.
• It provides formatted input/output using familiar printf-style formatting.
• It’s not usable inside most IDEs; must be run from a real terminal.