Java/JDK 6/Console

Console output with format

   <source lang="java">
 

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");
 }

}

 </source>
   
  
 
  

Console read Password

   <source lang="java">
 

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);
 }

}

 </source>
   
  
 
  

Java Console readLine

   <source lang="java">
 

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);
 }

}

 </source>
   
  
 
  

Masking a password with the Console class

   <source lang="java">

import java.io.Console; public class Main {

 public static void main(String[] args) {
   Console console = System.console();
   char passwordArray[] = console.readPassword("Enter your secret password: ");
   console.printf("Password entered was: %s%n", new String(passwordArray));
 }

}

 </source>
   
  
 
  

Password Prompting with java.io.Console

   <source lang="java">
 

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);
   }
 }

}

 </source>
   
  
 
  

Printing text with the Console class

   <source lang="java">

import java.io.Console; public class Main {

 public static void main(String[] args) {
   Console console = System.console();
   console.printf("%s%n", "this is a test");
 }

}

 </source>
   
  
 
  

Use Console class to read user input?

   <source lang="java">

import java.io.Console; import java.util.Arrays; public class Main {

 public static void main(String[] args) {
   Console console = System.console();
   String username = console.readLine("Username: ");
   char[] password = console.readPassword("Password: ");
   if (username.equals("admin") && String.valueOf(password).equals("secret")) {
     console.printf("Welcome to Java Application %1$s.\n", username);
     Arrays.fill(password, " ");
   } else {
     console.printf("Invalid username or password.\n");
   }
 }

}

 </source>