Question

我有一个文件扫描程序类，即用于从客户列表中读取名称（我还有另一个文件，即用于读取Customer对象，但这些文件正在读取正常）。我的列表看起来像这样（我只是跳过数字，然后将名称读入字符串name）：

1，巴比

2，乔

3，苏

4，玛丽

5，维克多

但出于某种原因，当我使用toString（）打印时，显示的唯一名称是Victor。我希望每个customer对象都有自己的相应名称。

问题：如何让lineScanner正确读取所有五个名称，然后将它们显示在toString（）中？

//reads in customer name info
File customerList = new File("./src/Customers.txt");
Scanner fileScanner = new Scanner(customerList);

//while there is a new line, goes to next one
while(fileScanner.hasNextLine())
{
    String line = fileScanner.nextLine();
    Scanner lineScanner = new Scanner(line);
    lineScanner.useDelimiter(",");

    //while there is a new attribute to read in on a given line, reads data
    while(lineScanner.hasNext())
    {
        lineScanner.next();
        name = lineScanner.next();
        customer1 = new Customer(ranking, name, tvTimeTotal1, exerciseTimeTotal1);
        customer2 = new Customer(ranking, name, tvTimeTotal2, exerciseTimeTotal2);
        customer3 = new Customer(ranking, name, tvTimeTotal3, exerciseTimeTotal3);
        customer4 = new Customer(ranking, name, tvTimeTotal4, exerciseTimeTotal4);
        customer5 = new Customer(ranking, name, tvTimeTotal5, exerciseTimeTotal5);
    }
}


System.out.println(customer1.toString());
System.out.println(customer2.toString());
System.out.println(customer3.toString());
System.out.println(customer4.toString());
System.out.println(customer5.toString());

Answer 1

这样的东西？

File customerList = new File("./src/Customers.txt");
Scanner fileScanner = new Scanner(customerList);

List<String> customerNames = new ArrayList<String>();
while(fileScanner.hasNextLine())
{
    String line = fileScanner.nextLine();
    Scanner lineScanner = new Scanner(line);
    lineScanner.useDelimiter(",");
    lineScanner.next(); // Discard number
    customerNames.add(lineScanner.next());
}

for(String name : customerNames)
{
    System.out.println(name);
}

Answer 2

您实际上是在每个迭代中为每个Customer对象写入相同的数据，即您在第一次迭代中在所有对象上编写Bobby，依此类推。所以最终你在循环之后留下Victor在所有对象上。尝试使用数组或ArrayList而不是此方法。参见@BertieWheen建议的那个。如果你是初学者而不是我建议你使用数组。

int i=0;
while(lineScanner.hasNext()){
  lineScanner.next();
  name = lineScanner.next();
  customer[i++] = new Customer(ranking, name, tvTimeTotal1, exerciseTimeTotal1);
}

或者如果您对ArrayList

感到满意

List customer=new ArrayList<Customer>();

while(lineScanner.hasNext()){
  lineScanner.next();
  name = lineScanner.next();
  customer.add(new Customer(ranking, name, tvTimeTotal1, exerciseTimeTotal1));
}

文件扫描仪扫描仪无法正确扫描所有信息

2 个答案: