将输出循环到Java中的.txt文件

Question

So here's my code:

import java.io.*;
import java.util.*;

public class Main {
public static void main(String[] args){

    ArrayList<Employee> ArrEmployee = new ArrayList<Employee>(); //  array for employee objects

        try {
            Scanner txtIn = new Scanner(new File("payroll.txt"));
            PrintWriter txtOut = new PrintWriter("payrollError.txt");


            while (txtIn.hasNext()) { // looping through the payroll.txt file and creating Employee objects from its data
                try{
                long EmployeeNumber = txtIn.nextLong();
                String EmployeeName = txtIn.next();
                String LastName = txtIn.next();
                double HoursWorked = txtIn.nextDouble();
                double HourlyWage = txtIn.nextDouble();
                if (HourlyWage > 10.35){ 
                    throw new InputMismatchException(); // throws exception if the hourly wage is less than 10.35$
                }
                else
                    ArrEmployee.add(new Employee(EmployeeNumber,EmployeeName,LastName,HoursWorked,HourlyWage)); // creates Employee objects according to the input payroll.txt
                }
                catch (InputMismatchException n) { // catching long,strings and doubles in the payroll.txt that aren't valid
                    txtOut.println(Employee.EmployeeNumber + " " + Employee.EmployeeName + " " + Employee.LastName + " " + Employee.HoursWorked + " " + Employee.HourlyWage);
                    System.out.println("lol");
                      }
                txtOut.close();
            }

        } catch (FileNotFoundException e) {
            System.out.println("File payroll.txt was not found.");

            }

          }

        }

I'm trying to output to a .txt file called payrollError.txt but for some reason, the while loop goes on infinitely...

I can't seem to find the problem in my main class and any help would be appreciated.

Here's my code from the payroll.txt :

31718 PHILLIP LENNOX 55.0 20.00
11528 NANCY TROOPER 40.0 10.45
16783 JOHN CONNAUGHT 30.5 10.00
10538 PETER DUNCAN 45.0 10.75
21O15 JAMES HAROLD 32.0 10.50
61326 HARRY KUHN 25.0 12.30
82465 MICHELLE BENOIT 50.0 18.50
31816 DANIELLE RAYMOND 35.5 15.25
73745 JACK O'TOOLE 28.0 11.50
81514 VICTORIA HALL 48.5 17.50
71854 ALI MOHUMAD 35.0 10.75
92012 ALLAN MARS 36.0 15.00
52853 MICHAEL BOONE 60.5 17.50
41714 JULIE HART 25.0 10.50
58342 MIKE HEINZ 28.2 16.85
62080 PIETRO SULA 32.5 11.50
21638 MICHEL RAE 40.5 12.50
52726 MITCHELL HACKETT 23,7 12.05

Basically it's supposed to loop through these (long,string,string,double,double) like by line, find any values that are invalid like a double written as 23,7 instead of 23.7 and output it to my file payrollError.txt.

My Employee class:

public class Employee {

     public static long EmployeeNumber;
     public static String EmployeeName;
     public static String LastName;
     public static double HoursWorked;
     public static double HourlyWage;

    public Employee(long EmployeeNumber, String EmployeeName, String LastName, double HoursWorked, double HourlyWage ){

        this.EmployeeNumber = EmployeeNumber;
        this.EmployeeName = EmployeeName;
        this.LastName = LastName;
        this.HoursWorked = HoursWorked;
        this.HourlyWage = HourlyWage;
    }
}

Answer 1

Don't close the output in your while loop body. Also, please follow Java variable naming conventions. Instead of displaying "lol" try and output the message you're writing. If you can't initialize the Employee it's hard to see how your existing method could get the values that were read. Finally, you need to close() your PrintWriter (or use a try-with-resources as below to do it for you). Something like

List<Employee> al = new ArrayList<>();
try (PrintWriter txtOut = new PrintWriter("payrollError.txt")) {
    Scanner txtIn = new Scanner(new File("payroll.txt"));
    while (txtIn.hasNext()) {
        long employeeNumber;
        String employeeName;
        String lastName;
        double hoursWorked;
        double hourlyWage;

        try {
            employeeNumber = txtIn.nextLong();
            employeeName = txtIn.next();
            lastName = txtIn.next();
            hoursWorked = txtIn.nextDouble();
            hourlyWage = txtIn.nextDouble();
            if (hourlyWage > 10.35) {
                throw new InputMismatchException();
            } else {
                al.add(new Employee(employeeNumber, employeeName,
                                lastName, hoursWorked, hourlyWage));
            }
        } catch (InputMismatchException n) {
            String msg = employeeNumber + " " + employeeName + " "
                    + lastName + " " + hoursWorked + " " + hourlyWage;
            txtOut.println(msg);
            System.out.println(msg);
        }
        // txtOut.close(); // <-- this is inside the loop.
    }
} catch (FileNotFoundException e) {
    System.out.println("File payroll.txt was not found.");
}

Your fields cannot be static in your Employee class! (And I would make them lowercase to follow Java naming conventions; otherwise they look like class names)

 private /* static */ long EmployeeNumber;
 private /* static */ String EmployeeName;
 private /* static */ String LastName;
 private /* static */ double HoursWorked;
 private /* static */ double HourlyWage;

Making the fields private is an example of encapsulation.

Answer 2

Better to use buffered reader and writer when using file streams .

modifying your code using those:

public class Main {
    public static void main(String[] args) {
        ArrayList<Employee> ArrEmployee = new ArrayList<Employee>();
        FileReader bfr = null;
        try {
            bfr = new FileReader(new File("payroll.txt"));
        } catch (FileNotFoundException e) {
            e.printStackTrace();
        }
        BufferedReader br = new BufferedReader(bfr);
        String EmployeeName = "no data";
        FileWriter bfw = null;
        try {
            bfw = new FileWriter("payroolError.txt");
        } catch (IOException e) {
            e.printStackTrace();
        }
        BufferedWriter txtOut = new BufferedWriter(bfw);

    try {
        while (br.read() != -1) {
            String temp = br.readLine();
            Pattern p = Pattern.compile(" ");
            String[] items = p.split(temp);
            try {
                int EmployeeNumber = Integer.parseInt(items[0]);
                EmployeeName = items[1];
                String LastName = items[2];
                double HoursWorked = Double.parseDouble(items[3]);
                double HourlyWage = Double.parseDouble(items[4]);
                if (HourlyWage > 10.35) {
                    throw new InputMismatchException();
                } else {
                    ArrEmployee
                            .add(new Employee(EmployeeNumber, EmployeeName,
                                    LastName, HoursWorked, HourlyWage));
                }
            } catch (NumberFormatException n) {
                txtOut.write(EmployeeName);
            } catch (InputMismatchException n) {
                txtOut.write(EmployeeName);
            }
        }
    } catch (IOException e) {
        e.printStackTrace();
    }

}}