java.io.Console

The new released JDK6 includes a new Console class, which can be found in the java.io package. This class adds some new features to enhance and simplify command-line applications. It includes a method specifically for reading passwords that disables console echo and
returns a char array for security purpose.

The example given below read the password from the console but the password will not be echoed to the console screen. If the given password matches with the specified characters as “javajazzup” then a message “Access granted” is displayed; otherwise it displays “Access denied” as an output.

PasswordPrompting.java
import java.io.Console;
import java.util.Arrays;
public class PasswordPrompting {
public static void main(String[] args) {
Console console = System.console();
if (console == null) {
System.out.println(“Console is not
available”);
System.exit(1);
}char[] password =
“javajazzup”.toCharArray();
/* Read password, the password will not be
echoed to the console screen and returned as
an array of characters.*/
char[] passwordEntered =
console.readPassword(“Enter password: “);
if (Arrays.equals(password,
passwordEntered)) {
System.out.println(“\n Access granted
\n”);
// Clear the password after validation
successful
Arrays.fill(password, ‘ ‘);
Arrays.fill(passwordEntered, ‘ ‘);
} else {
System.out.println(“Access denied”);
System.exit(1);
}
}
}