scanner类，next（）和nextline（）区别

public class Demo01 {
    public Demo01() {
    }

    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        System.out.println("输入内容：");
        if (scanner.hasNext()) {
            String str = scanner.next();
            System.out.println("输出的内容为：" + str);
        }

        scanner.close();
    }
}

public class Demo02 {
    public Demo02() {
    }

    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        System.out.println("使用next方式接收：");
        if (scanner.hasNextLine()) {
            String str = scanner.nextLine();
            System.out.println("输出的内容为：" + str);
        }

        scanner.close();
    }
}