Question

我正在为java类创建一个员工时钟。我的程序的这一部分需要在接受“打卡时间”之前检查是否存在“打卡时间”。

当我只使用if循环时，该部分似乎有效。当我添加else时，它会忽略if并执行else。

我能否就更好的方法获得一些反馈？

public static void punchIn() throws IOException {
    Scanner sc = new Scanner(System.in);
    System.out.print("Enter Date and time (format MM/dd/yyyy HH:mm:ss): ");
    String timeentry = sc.nextLine();

    System.out.print("Enter the employee ID number: ");
    String idnumber = sc.nextLine() + " ";

    String inorout = "in";

    System.out.println("The Punch-in date / time is: " + timeentry);
    System.out.println("The employee ID number is: " + idnumber);
    System.out.println("The employee is punched-" + inorout);

    PunchinPunchoutData product = new PunchinPunchoutData();
    product.setTimeentry(timeentry);
    product.setIdnumber(idnumber);
    product.setInorout(inorout);

    productDAO.punchIn(product);

    System.out.println();
    System.out.print("Press enter to continue ");
    sc.nextLine();
}


public static void punchOut() throws FileNotFoundException, IOException {

    Scanner sc = new Scanner(System.in);
    System.out.print("Enter Date and time (format MM/dd/yyyy HH:mm:ss): ");
    String timeentry = sc.nextLine();

    br = new BufferedReader(new FileReader("timeclock1.txt"));

    String line = "";

    System.out.print("Enter an employee ID number: ");
    String idnumber = sc.next() + " ";//read the choice
    sc.nextLine();// discard any other data entered on the line

    while ((line = br.readLine()) != null) {

        if (line.contains(idnumber + " ") && line.endsWith("in")) {
            break;
        }

        else  { 
            System.out.println("There is no punch-in record for ID number: 
            " + idnumber);
            System.out.println("A punch-in entry must be saved first");
            punchIn();
            break;
        }
    }

    String inorout = "out";

    System.out.println("The Punch-out date / time is: " + timeentry);
    System.out.println("The employee ID number is: " + idnumber);
    System.out.println("The employee is punched-" + inorout + ".");

    PunchinPunchoutData product = new PunchinPunchoutData();
    product.setTimeentry(timeentry);
    product.setIdnumber(idnumber);
    product.setInorout(inorout);

    productDAO.punchOut(product);

    System.out.println();
    System.out.print("Press enter to continue ");
    sc.nextLine();

}

Answer 1

您似乎正在逐行阅读文件，以检查员工是否有＆＃34;打入＆＃34;记录。在您的代码中，当您拥有一条不属于该员工的行时，您正在调用punchIn，这很可能会添加一个＆＃34; punch-in＆＃34;每次调用punchOut时。您应该遍历整个文件，并且只有当文件中没有行包含记录时才调用punchIn。

boolean foundPunchIn = false;

while ((line = br.readLine()) != null) {
    if (line.contains(idnumber + " ") && line.endsWith("in")) {
       foundPunchIn = true;
       break;
    }   
}

if(!foundPunchIn) {
    System.out.println("There is no punch-in record for ID number: " + idnumber);
    System.out.println("A punch-in entry must be saved first");
    punchIn();
}

String inorout = "out";
...

Java：如何在将数据保存到文本文件之前检查字符串？

1 个答案: