java - 如何将文本文件中的内容存储到数组列表

Question

我需要从内容以制表符分隔的文本文件中读取员工详细信息。我有两个类(class)，如下所示:

package employee;

import java.io.BufferedReader;
import java.io.FileReader;
import java.io.IOException;
import java.util.ArrayList;

public class Employee {

    public static void main(String[] args) throws IOException{

        ArrayList<Employee_Info> ar_emp = new ArrayList<Employee_Info>();
        BufferedReader br = null;
        Employee_Info e = null;
        br = new BufferedReader(new FileReader("C:/Users/home/Desktop/Emp_Details.txt"));
        String line;
        try {
            while ((line = br.readLine()) != null) {
                String data[] = line.split("\t");
                 e = new Employee_Info();
                 e.setDept_id(Integer.parseInt(data[0]));
                 e.setEmp_name(data[1]);
                 e.setCity(data[2]);
                 e.setSalary(Integer.parseInt(data[3]));

                 ar_emp.add(e);
            }
            for(Employee_Info i : ar_emp){
                System.out.println(i.getDept_id()+","+i.getEmp_name()+","+i.getCity()+","+i.getSalary());

            }
            br.close();

        } catch (IOException io) {
            io.printStackTrace();
        }
    }
}

和

package employee;

public class Employee_Info {

    private static int dept_id;
    private static String emp_name;
    private static String city;
    private static int salary;

    public static int getDept_id() {
        return dept_id;
    }
    public static void setDept_id(int dept_id) {
        Employee_Info.dept_id = dept_id;
    }
    public static String getEmp_name() {
        return emp_name;
    }
    public static void setEmp_name(String emp_name) {
        Employee_Info.emp_name = emp_name;
    }
    public static String getCity() {
        return city;
    }
    public static void setCity(String city) {
        Employee_Info.city = city;
    }
    public static int getSalary() {
        return salary;
    }
    public static void setSalary(int salary) {
        Employee_Info.salary = salary;
    }


}

我试图读取的文本文件如下:

10  A   Denver  100000
10  B   Houston 110000
10  C   New York    90000
10  D   Houston 95000
20  F   Houston 120000
20  G   New York    90000
20  H   New York    90000
20  I   Houston 125000
30  J   Houston 92000
30  K   Denver  102000
30  L   Denver  102000
30  M   Houston 85000

当我执行 Employee 类来打印 ArrayList ar_emp 的内容时，我得到以下重复输出:

30,M,Houston,85000
30,M,Houston,85000
30,M,Houston,85000
30,M,Houston,85000
30,M,Houston,85000
30,M,Houston,85000
30,M,Houston,85000
30,M,Houston,85000
30,M,Houston,85000
30,M,Houston,85000
30,M,Houston,85000
30,M,Houston,85000

请帮忙。

Answer 1

您将 Employee_Info 的所有属性声明为 static 字段。它们不绑定(bind)到类的实例，而是绑定(bind)到类本身。因此，该类的所有实例共享相同的值。从字段和方法中删除 static 关键字。

您应该使用 IDE(例如 Eclipse)，它应该警告您有关实例上的静态方法调用的信息。