Java Tutorial/Development/Java Console

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Console output with format

import java.io.Console;
import java.sql.SQLException;
public class MainClass {
  public static void main(String[] args) throws ClassNotFoundException, SQLException {
    Console console = System.console();
    if (console == null) {
      System.err.println("sales: unable to obtain console");
      return;
    }
    console.printf("%s ", "string");
  }
}





Console read Password

import java.io.Console;
import java.sql.SQLException;
public class MainClass {
  public static void main(String[] args) throws ClassNotFoundException, SQLException {
    Console console = System.console();
    if (console == null) {
      System.err.println("sales: unable to obtain console");
      return;
    }
    String password = new String (console.readPassword ("Enter password: "));
    System.out.println(password);
  }
}





Java Console readLine

import java.io.Console;
import java.sql.SQLException;
public class MainClass {
  public static void main(String[] args) throws ClassNotFoundException, SQLException {
    Console console = System.console();
    if (console == null) {
      System.err.println("sales: unable to obtain console");
      return;
    }
    String username = console.readLine("Enter username: ");
    System.out.println(username);
  }
}





Password Prompting with java.io.Console

import java.io.Console;
import java.util.Arrays;
public class PasswordPromptingDemo {
  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 = "mustang".toCharArray();
    char[] passwordEntered = console.readPassword("Enter password: ");
    if (Arrays.equals(password, passwordEntered)) {
      System.out.println("\n Access granted \n");
      Arrays.fill(password, " ");
      Arrays.fill(passwordEntered, " ");
      System.out.println("OK ...");
    } else {
      System.out.println("Access denied");
      System.exit(1);
    }
  }
}