将输入重定向到控制台读取

/** from n o w  j a v a  . c o m**/

import java.util.Scanner;


public class Main {

  public static void main(String[] args) {

    Scanner keyboard = new Scanner(System.in);

    int val;

    System.out.print("Enter an integer please:");

    val = keyboard.nextInt();

    val *= val; // squared the input value

    System.out.println("Squared value=" + val);

  }

}