How to read input from console (keyboard) in Java?

There are few ways to read input string from  your console/keyboard. The following smaple code shows how to read a string from the console/keyboard by using Java.

public class ConsoleReadingDemo {

    public static void main(String[] args) {

        // ====
        BufferedReader reader = new BufferedReader(new InputStreamReader(System.in));
        System.out.print("Please enter user name : ");
        String username = null;
        try {
            username = reader.readLine();
        } catch (IOException e) {
            e.printStackTrace();
        }
        System.out.println("You entered : " + username);

        // ===== In Java 5, Java.util,Scanner is used for this purpose.
        Scanner in = new Scanner(System.in);
        System.out.print("Please enter user name : ");
        username = in.nextLine();      
        System.out.println("You entered : " + username);
 
 
        // ====== Java 6
        Console console = System.console();
        username = console.readLine("Please enter user name : ");   
        System.out.println("You entered : " + username);

    }
}

The last part of code used java.io.Console class. you can not get Console instance from System.Console() when running the demo code through Eclipse. Because eclipse runs your application as a background process and not as a top-level process with a system console.

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