Java ArrayList未返回预期数据

我不知道我在做什么，如果能得到任何帮助，我将不胜感激。 我正在读取具有以下代码的文本文件：

7
10 416-555-6667 Burgess Smith 15
15 905-777-8888 Thomas Patel 10
20 905-111-2222 Morris J. Stevenson 5
25 416-222-3333 Spencer Larson 30
30 416-333-4444 Adams Doe 18
35 905-122-5454 Price Hanks 15
40 905-343-5151 Clement L. Webster 8
private static void fileReader() throws FileNotFoundException
{
    int eId = 0;
    String nme = "";
    String phne = "";
    int yrs = 0;
    String line ="";
    Employee emp = new Employee(eId, nme, phne, yrs);
    File inputfile = new File("Emp.txt");
    Scanner in = new Scanner(inputfile);
    n = in.nextInt() - 1;
    in.nextLine();
    in.useDelimiter("");
    for (int i=0;i<=n;i++)          
    {
        int l = 0;
        int m = 0;
        int n = 0;
        line = in.nextLine();
        while (Character.isDigit(line.charAt(l)))
        {
            l++;
        }
        m = l + 1;
        while (!Character.isLetter(line.charAt(m)) && !Character.isWhitespace(line.charAt(m)))
        {
            m++;
        }
            n = m + 1;
            while (!Character.isDigit(line.charAt(n)))
            {
                n++;
            }
            eId = Integer.parseInt(line.substring(0, l));
            emp.setEmpId(eId);
            phne = line.substring(l + 1, m - 1);
            emp.setTelephone(phne);
            nme = line.substring(m + 1, n - 1);
            emp.setName(nme);
            yrs = Integer.parseInt(line.substring(n));
            emp.setYears(yrs);
            empArr.add(i, emp);
        }
    in.close();
}

}

当我在其for循环之外调用ArrayList的get方法时，每个索引处的文本将被最后一个索引处的文本覆盖

我想我在这里遗漏了一些构造函数和对象的基本概念

---

感谢您的帮助。谢谢。

你的直觉是正确的，你错过了emp对象的创建。必须将emp对象创建移动到循环中

您的Employee类和getter/setter方法编写正确

重写fileReader（）方法，如下所示：-

String line ="";    
//Declare an Arraylist for an Employee
List<Employee> employee = new ArrayList<Employee>();            
//Read a file
File inputfile = new File("Emp.txt file path");    
Scanner in = new Scanner(inputfile);

//Reading a number from a first sentence 
int n = Integer.parseInt(in.nextLine());     

for (int i=0;i<n;i++) {
    // Reading each sentence
    line = in.nextLine();   
    //Parse an Emp id 
    int eId = Integer.parseInt(line.substring(0, 2));
    //Parse a phone number  
    String phone = line.substring(3, 14);
    //Parse a name         
    String name = line.split("\\d+")[4];          
    //Parse years
    int years = Integer.parseInt(line.split("\\D+")[4]); 
    //Now create an object by putting all above values in a constructor
    Employee emp1 = new Employee(eId, name, phone, years);
    //Add that object in an arraylist
    employee.add(emp1);
}

//As you have overridden toString method, print an arraylist
System.out.println(emp.toString());   
//Closing the scanner
in.close();
}

字符串行=”；
//为员工声明Arraylist
List employee=new ArrayList（）；
//读文件
File inputfile=新文件（“Emp.txt文件路径”）；
扫描仪输入=新扫描仪（输入文件）；
//读第一句话中的数字
int n=Integer.parseInt（in.nextLine（））；
对于（int i=0；i在什么ArrayList上获取方法？您的直觉是正确的，您缺少emp对象创建。您必须将emp对象创建移动到循环中。以下是我尝试使用的示例：@Gangadhar Kairi我将尝试此方法thanks@GangadharKairi成功了，谢谢
String line ="";    
//Declare an Arraylist for an Employee
List<Employee> employee = new ArrayList<Employee>();            
//Read a file
File inputfile = new File("Emp.txt file path");    
Scanner in = new Scanner(inputfile);

//Reading a number from a first sentence 
int n = Integer.parseInt(in.nextLine());     

for (int i=0;i<n;i++) {
    // Reading each sentence
    line = in.nextLine();   
    //Parse an Emp id 
    int eId = Integer.parseInt(line.substring(0, 2));
    //Parse a phone number  
    String phone = line.substring(3, 14);
    //Parse a name         
    String name = line.split("\\d+")[4];          
    //Parse years
    int years = Integer.parseInt(line.split("\\D+")[4]); 
    //Now create an object by putting all above values in a constructor
    Employee emp1 = new Employee(eId, name, phone, years);
    //Add that object in an arraylist
    employee.add(emp1);
}

//As you have overridden toString method, print an arraylist
System.out.println(emp.toString());   
//Closing the scanner
in.close();
}