如何使用java.util.Scanner类从控制台读取用户输入?
在JDK1.5中java.util.Scanner,引入了一个类来处理控制台应用程序中的用户输入。此类使我们能够在控制台应用程序中读取字符串,整数,长整数等。
package org.nhooo.example.util;
import java.util.Scanner;
public class ScannerDemo {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        //读取用户名的字符串输入
        System.out.print("Username: ");
        String username = scanner.nextLine();
        //读取密码输入的字符串
        System.out.print("Password: ");
        String password = scanner.nextLine();
        //读取整数输入以应对另一个挑战
        System.out.print("What is 2 + 2: ");
        int result = scanner.nextInt();
        if (username.equals("admin")
                && password.equals("secret") && result == 4) {
            System.out.println("Welcome to Java Application");
        } else {
            System.out.println("Invalid username or password, " +
                    "access denied!");
        }
    }
}代码段的结果:
Username: admin Password: secret What is 2 + 2: 4 Welcome to Java Application