java - 如果 ArrayList 中的字符串包含 ""，则获取索引

Question

我正在尝试将文件读取到数组列表中。这个问题已经解决了，我将文件的一行放入数组列表中的一个 block 中。但是，在这个过程中，如果要插入的行包含某些内容，我想获取 block 的索引。这是我到目前为止所做的。我被困住了。

public class practice3 {

    public static void main(String[] args) throws Exception {
        Scanner data = new Scanner(new FileReader("StudData1.txt"));
        ArrayList<String> ArrayData = new ArrayList<String>();
        int i = 0;
        while (data.hasNextLine()) {
            ArrayData.add(i, data.nextLine());
            if (data.nextLine().contains("ID: ")) {
                System.out.print(ArrayData.indexOf(ArrayData.contains("ID: ")));
            }
            i = i + 1;
        }
        // System.out.print(ArrayData.get(2));
        // System.out.print(ArrayData.size());
    }
}

示例:

************************
Student N. 1  
ID: 4450
Surname: Wol
Name: Verine
************************

--------------------------------
Subject N. 1 : a. Boat Mantenance
--------------------------------
Homework 1: 89

Homework 2: 56

Homework 3: 65

Homework 4: 3

Exam 1: 35

Exam 2: 45

Exam 3: 89

Exam 4: 99

Answer 1

请试试这个:

    while(data.hasNextLine())
    {
        //if you call nextLine() two times you will get two different items
        String data = data.nextLine();  
        ArrayData.add(i, data);

        if (data.contains("ID: "))
        {
            System.out.print(ArrayData.indexOf(data));  
           //check the index of data, but that should be equal to i. no idea what you want to do here?
        }
        i++;
    }