以文本格式存储对象程序实例

package textFile;

import java.io.*;
import java.text.ParseException;
import java.time.*;
import java.time.format.DateTimeFormatter;
import java.util.*;

import abstractClass.Employee;

public class TestFileTest {

    public static void main(String[] args) throws IOException, ParseException {
        Employee[] staff = new Employee[3];
        staff[0] = new Employee("First", 1111, 1987, 12, 15);
        staff[1] = new Employee("Second", 2222, 1989, 10, 1);
        staff[2] = new Employee("Third", 3333, 1990, 3, 15);

        try (PrintWriter out = new PrintWriter("employee.txt", "UTF-8")) {
            writeData(staff, out);
        }

        try (Scanner in = new Scanner(new FileInputStream("employee.txt"), "UTF-8")) {
            Employee[] newStaff = readData(in);
            for (Employee e : newStaff)
                System.out.println(e);
        }
    }

    private static void writeData(Employee[] employees, PrintWriter out) throws IOException {
        out.println(employees.length);
        for (Employee e : employees)
            writeEmployee(out, e);
    }

    private static Employee[] readData(Scanner in) throws ParseException {
        int n = in.nextInt();
        in.nextLine();

        Employee[] employees = new Employee[n];
        for (int i = 0; i < n; i++) {
            employees[i] = readEmployee(in);
        }
        return employees;
    }

    public static void writeEmployee(PrintWriter out, Employee e) {
        out.println(e.getName() + "|" + e.getSalary() + "|" + e.getHireDay());
    }

    public static Employee readEmployee(Scanner in) throws ParseException {
        String line = in.nextLine();
        String[] tokens = line.split("\\|");
        //System.out.println(tokens[2]);
        String name = tokens[0];
        double salary = Double.parseDouble(tokens[1]);

        DateTimeFormatter df = DateTimeFormatter.ofPattern("EEE MMM dd HH:mm:ss 'CST' yyyy", Locale.US);
        LocalDate hireDate = LocalDate.parse(tokens[2], df);   
        int year = hireDate.getYear();
        int month = hireDate.getMonthValue();
        int day = hireDate.getDayOfMonth();
        return new Employee(name, salary, year, month, day);
    }
}