JDK6-使用java.io.Console显示输入信息

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);   
  }   
}