java获取当前屏幕文本,使用文本文件的Java登录屏幕

╰+哭是因爲堅強的太久メ 2022-08-29 14:55 20阅读 0赞

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I am creating a java application and I need to get the user PINs from the text file. I used the following code below, but is it not working properly. Could anyone please help me out soon.....

String typedPIN="";

Menus obj1=new Menus();

BufferedReader getIt=new BufferedReader(new InputStreamReader(System.in));

String userPIN="";

try\{

BufferedReader br = new BufferedReader(new FileReader(new File("D:\\\\Studies\\\\BCAS\\\\HND\\\\Semester 1\\\\Programming Concepts\\\\Assignment\\\\AccountPIN.tab")));

String strLine=null ;

System.out.println("Enter PIN");

userPIN=getIt.readLine();

while ((strLine = br.readLine()) != null) \{

if(userPIN.equals(strLine))\{

System.out.println("You have login!");

obj1.MainMenu();

\}catch (Exception e)\{//Catch exception if any

System.err.println("Error: " + e.getMessage());

解决方案

Assuming this is your input data

PIN AccountNo Balance

1598 01-10-102203-0 95000

4895 01-10-102248-0 45000

9512 01-10-102215-0 125000

6125 01-10-102248 85000

You will need to split each line into its consituent parts, you could use the Scanner class to do this, as it will let you extract the pin / account number as Strings and the balance as a Double/Integer.

At the moment you are comparing the user input against the whole line, so you would need to enter a pin 1598 01-10-102203-0 95000 rather than 1598 in order to login.

I suggest you split this into to two methods, one which when given a file returns a Collection of Account objects, and another which handles the login.

You could re-write your while loop to enable you to give a useful error message if you don't get a valid pin, e.g.

final File data = new File("D:\\\\Studies\\\\BCAS\\\\HND\\\\Semester 1\\\\Programming Concepts\\\\Assignment\\\\AccountPIN.tab");

Account userAcc = null;

for (Account acc : getAccounts(data)) \{

if(userPIN.equals(acc.getPin()))\{

userAcc = acc;

if (userAcc == null) \{

obj1.MainMenu();

\} else \{

// display error

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