您的程序需要搜索这三个文件，以找到在所有三个商店使用的信用卡号码。然后输出这个数字。
您可以遵循下面的粗略伪代码。请注意，它是不完整的，您可能需要解释丢失的部分。正确地记录和注解代码。
main方法：处理first store声明并初始化一个布尔变量match，当match为false时从文件中读取信用卡号，并且信用卡号不为null，将信用卡号传递给处理第二个存储的方法。如果返回true，则将match设置为true，否则从（2）重复。如果match为true或信用卡号为null，则完成程序。根据match的值，输出匹配结果或指示未找到匹配项。
这就是问题所在，我已经编写了代码，但问题是它在另一个文本文件中逐行比较，而不是只取一个值，然后将它与另一个文件中的整个值进行比较。请帮助，一个小的想法也将不胜感激。请在概念上帮助我！

public static void main(String[] args) throws IOException {
        Boolean match = false;
        File file = new File("/Users/User/Desktop/CreditCards/creditCards1.txt");
        Scanner scan = new Scanner(file);
        String credit_card_number = "";
        while (scan.hasNextLine() && !match ) {
             credit_card_number = scan.nextLine();
             match = second_Store(credit_card_number);
            System.out.println(credit_card_number);

        } scan.close();
        if (match == true){
            ;
        }else
            System.out.println(credit_card_number);
        System.out.println(match);

    }

    public static Boolean second_Store(String creditCard) throws FileNotFoundException {
        Boolean match = false;
        File file = new File("/Users/User/Desktop/CreditCards/creditCards2.txt");
        Scanner scan = new Scanner(file);
        String credit_card_number;String toCompare = creditCard;

        do{
            credit_card_number = scan.nextLine();
            if (credit_card_number.equals(creditCard)){
                third_Store(credit_card_number);
                System.out.println(credit_card_number);
                match = true;
            }else
                continue;

        }while(match && scan.hasNextLine());
        return match;

    }

    public static Boolean third_Store(String creditCard) throws FileNotFoundException {
        Boolean match = false;
        File file = new File("/Users/User/Desktop/CreditCards/creditCards3.txt");
        Scanner scan = new Scanner(file);
        String credit_card_number;
        do{
            credit_card_number = scan.nextLine();
            if(credit_card_number.equals(creditCard)){
                match = true;
                System.out.println(credit_card_number);
            }
            else
                continue;

            } while (match && scan.hasNextLine());
        return match;
    }
}