I already wrote an ATM program which did store only three account number, password and balance but now I want to get these information from a file which would be read to the program and by entering the information the program should search the file and find the line that fit the information that I entered first for account number then for password and if all match one of 50000 account in the file show the balance of that account and also if I need to deposit or withdraw from one of the account it would save the new balance and next time if I sign in with that account it would show me the new balance which I changed by adding deposit to it or withdraw mony from it!
I know that some how my program reads the file and copy it to another file and also in another method erase the copy file that ?I have and should replace it with the new information(balance) but I don't know how to do it! would someone please help me and walk me through it.
This is the one that I wrote with 3 accounts information stored in the program itself:
Please please someone help me as soon as possible!

import java.util.Scanner;//name of the package(library)that includes the * class

public class ATM{//name of the program

	public static Scanner kbd;//Scanner kbd function
	public static void main(String[] args) {// the main program with the word void doesn't let anything out 
		String userAnswer = null;//declaring the string
		Scanner kbd = new Scanner(System.in); // declaring the function
		double accountbalance = 0, depositamount = 0, withdrawalbalance= 0;//declaring the variables, accountbalance, depositamount, withdrawalbalance, as double
		String acctNum,pwd;//declaring acctNum, pwd as string
		String acctres;//declaring acctres as string
		int counter=0;//declaring counter as int
		int Choice;//declaring Choice as int
		do//gives the do-while loop the condition to repeat the statement
		{
			System.out.println("Please enter your account number: ");//gives the system command to print

			acctNum = kbd.nextLine();//getting the inputs and allocating 
			System.out.println("Please enter your account password: ");//gives the system command to print
			pwd = kbd.nextLine();//getting the inputs and allocating 

			acctres=checkID(acctNum,pwd);//Initializing acctres

			if(!acctres.equals("error"))// checking for the situation of the acctres variable for error
			{
				accountbalance = Double.parseDouble(acctres);//Initializing accountbalance

				do//gives the do-while loop the condition to repeat the statement
				{
					Choice = Menu();//Initializing Menu()
					System.out.println(Choice);//gives the system command to print
					if (Choice == 1)//checking for input 1
					{
						System.out.println("Your Balance is: " + accountbalance + "$");//gives the system command to print
					}
					else if (Choice == 2)//checking for input 2
					{
						System.out.println("How much would you like to deposit to your account? ");//gives the system command to print
						depositamount=kbd.nextDouble();//getting the inputs and allocating
						double calculatebalance = Deposit(accountbalance, depositamount);//Initializing calculatebalance
						System.out.println("Your Balance with your Deposit now is: " + calculatebalance + "$");//gives the system command to print
					}
					else if (Choice == 3)//checking for input 3
					{
						System.out.println("How much would you like to withdrawal from your account? ");//gives the system command to print
						withdrawalbalance=kbd.nextDouble();//getting the inputs and allocating
						double calculatebalance1 = Withdraw(accountbalance, withdrawalbalance);//Initializing calculatebalance1
						System.out.println("You Balance now is: " + calculatebalance1 + "$");//gives the system command to print
					}
					else// checking for the other inputs except the ones which were mentioned
					{
						System.out.println("Do you want to Log Out? (Y or N) ");//gives the system command to print
						userAnswer=kbd.next();//getting the inputs and allocating
						userAnswer=userAnswer.toUpperCase();//to ignore the upper case or lower case input and count them as the same
						if (userAnswer.equals("Y"))//checking for the situation of userAnswer for being equal Y which means yes
						{
							System.out.println("You are now logged out!");//gives the system command to print
							System.exit(0);// gives command for the if statement
						}

					}
				}while ((Choice <=4)|| (userAnswer.equals("N")));//Checking input N

			}
			else// checking for other input except the ones that already were mentioned
			{
				System.out.println("Error");//gives the system command to print
				counter++;//Increasing the counter by 1
				System.out.println(counter);//gives the system command to print
			}

		}while(counter<3);//checking for the counter to be less than 3 or not	

		System.out.println("You have exceeded the required amount of times.");//gives the system command to print	
	}	

	public static String checkID(String acctNum, String pwd)//separating the part from the main program as a new function in the main function
	{
		String result = "error";//declaring the result as string
		// Strings a, b, and c contain the valid account numbers and passwords.
		// For each string, the account number is listed first, followed by
		// a space, followed by the password for the account, followed by a space,
		// followed by the current balance.
		String a = "44567-5 mypassword 520.36";//declaring string a which id equal 44567-5 mypassword 520.36 in this function
		String b = "12345-6 anotherpassword 48.20";//declaring string b which id equal 12345-6 anotherpassword 48.20 in this function
		String c = "54321-0 betterpassword 96.74";//declaring string c which id equal 54321-0 betterpassword 96.74 in this function
		String d=a.substring(0,7);//declaring string d in this function
		String e=a.substring(8,18);//declaring string e in this function
		String eres=a.substring(19);//declaring string eres in this function
		String f=b.substring(0,7);//declaring string f in this function
		String g=b.substring(8,23);//declaring string g in this function
		String gres=b.substring(24);//declaring string gres in this function
		String h=c.substring(0,7);//declaring string h in this function
		String i=c.substring(8,22);//declaring string i in this function
		String ires=c.substring(23);//declaring string ires in this function
		if(acctNum.equals(d) && pwd.equals(e))//checking for account number and password
		{
			result=eres;//gives commands for the if statement
		}  
		else if(acctNum.equals(f) && pwd.equals(g))//checking for account number and password
		{
			result=gres;//gives commands for the if statement
		}
		else if(acctNum.equals(h) && pwd.equals(i))//checking for account number and password
		{
			result=ires;//gives commands for the if statement
		}
		return result;//to get data out of the function and takes the value with it only once 
	}

	public static double Displaybalance1(double accountbalance)//separating the part from the main program as a new function in the main function          
	{

		return accountbalance;//to get data out of the function and takes the value with it only once 
	}

	public static double Deposit(double accountbalance, double depositamount)//separating the part from the main program as a new function in the main function          
	{
		return accountbalance+ depositamount;//to get data out of the function and takes the value with it only once 
	}

	public static double Withdraw(double accountbalance, double withdrawalbalance)//separating the part from the main program as a new function in the main function          
	{
		double newbalance1 = 0;//declaring the variables, newbalance1, as double
		if (withdrawalbalance<=accountbalance)//checking the condition in the parentheses(if withdrawalamount is less than or equal the accontbalance or not)
		{
			newbalance1 = accountbalance - withdrawalbalance;//gives the system command to print the calculated amount
		}
		else if (withdrawalbalance>accountbalance)//checking the condition in the parentheses(if withdrawalamount is more than the accontbalance or not)
		{
			newbalance1 = accountbalance;//declaring the newbalance1 as previous accountbalance without change
			System.out.println("error, that is impossible! your account balance still is: " + newbalance1);//gives the system command to print the accountbalance without changing it
		}
		return newbalance1;//to get data out of the function and takes the value with it only once 
	}
	public static int Menu()//separating the part from the main program as a new function in the main function

	{
		int Option ;//declaring the variables, Size, as int
		do//gives the do-while loop the condition to repeat the statement
		{
			Scanner kbd1 = new Scanner(System.in);// declaring the function
			System.out.println("1.  Display Balance ");//gives the system command to print
			System.out.println("2.  Deposit ");//gives the system command to print
			System.out.println("3.  Withdraw ");//gives the system command to print
			System.out.println("4.  Log Out ");//gives the system command to print
			System.out.println("Enter your option");//gives the system command to print
			Option = kbd1.nextInt();//getting the inputs and allocating
			if ((Option<=0)&&(Option > 4))//checking for the statement in parentheses(Smaller or equal 0 or bigger than 4 inputs)
			{
				System.out.println("Error! Choose again: ");//gives the system command to print 
			}
		}while ((Option<=0)&&(Option > 4));//gives the while loop the condition to stop the repeating statement

		return Option;//to get data out of the function and takes the value with it only once 
	}		
}
gnohc commented: 15 +0

please write you code inside the BB code required cause some of us can't understand.. tnx

commented: i want to learn Java. What are your references +0

Do you have one table for "account"/"deposit"/"withdraw" "balance"/"last_update" ? Every time when any account has any transaction you will save it into table, so next time you log in you will check there is any "new" balance from the table first. If yes, you will show it.


Albert

pano po gawin sa java yung kunyare nag-enter ako nang number tapos ang lalabas asteris(*)

commented: In english and in a new thread -1
commented: english please, and non nonsense -2

pano po gawin sa java yung kunyare nag-enter ako nang number tapos ang lalabas asteris(*)

Start a new thread.

how to program the atm

Hi, can u add a biometric authentication code to this? please help me out. need it for my project. you can send it to my box. <EMAIL SNIPPED>

commented: For hijacking an old thread and trying to get credit from other people's work -1

@walexy: No, you're just going to have to do your own work.

@sund Please read the Daniweb Member Rules before posting again.

DaniWeb Member Rules include:

"Do not hijack old threads by posting a new question as a reply to an old one"
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Please start your own new thread for your question

Many of our members have English as their second (or third...) language, so "leet" or other semi-coded language will be unreasonably difficult. Keep to proper English.
DaniWeb Member Rules include:
"Do post in full-sentence English"
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pano po kung ganito ang output na dapat lalabas?

[1]  DEPOSIT
[2]  WITHDRAW
ATM        [3]  INQUIRE BALANCE 
[4]  EXIT

Please observe DaniWeb rules, including
"Do post in full-sentence English"
thank you.

I'm in the same boat with you I have to write a project just like you....didn't you complite ti so far?

This thread is 8 years old and the original poster isn'there now.
Please start a new thread for your project and people will help you.

Give output of this program

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