【问题】

My project has names and scores for 16 students in a class. A text file has their names and their lab/quiz scores. I need to read this data into parallel arrays.

This is what the text files looks like:

Line 1: Puckett, Karen
Line 2: 10 10 9.5 10 10 8 9.5 10 10 10 9 10 10 10 0
Line 3: 4 3 5 3 5 2 3 2 1.5 1 5 3.5
Line 4: 17.5 24 22 23.5 22 23
Line 5: 90 91
Line 6: 96

This is repeated for each student with no gap lines. The format in the file is

• Line 1: name

• Line 2: lab grades

• Line 3: quiz grades

• Line 4: project grades

• Line 5: exam grades, and

• Line 6: final exam grade.

This format is repeated for each of the sixteen students.

I'm struggling with how to read them into each line into their own arrays. Would I need to make one for each student? Because in the end I must be able to sort the students by grade, but I'm not asking for help with that. Just on how I would read the data for each student and their grades into arrays. And how to store them so that I would be able to distinguish which grades belong to which students. Below is what I have done so far:

public class JavaApplication39 {

    /**
     * @param args the command line arguments
     */
    public static void main(String[] args) throws Exception {
        // TODO code application logic here
        //declare file object, and connect to scanner  object
        File myFile = new File(System.getProperty("user.dir") + "/src/scores.txt");
        if (!myFile.exists()) {
            System.out.println("Unable to open the file");
            System.exit(0);
        }
        Scanner inputFile = new Scanner(myFile);

        //create method to return percent earned 
        //create name array
        String[] nameList = getNameList(inputFile);
        System.out.println(Arrays.toString(nameList));

        //create array of grades and then get average and return array of averages
        double[] labGrade = getLabGrade(inputFile);
        System.out.println(Arrays.toString(labGrade));
    }

    public static String[] getNameList(Scanner object) {
        String[] nameList = new String[16];
        while (object.hasNext()) {
            for (int i = 0; i < 16; i++) {
                nameList[i] = object.nextLine();
                object.nextLine();
                object.nextLine();
                object.nextLine();
                object.nextLine();
                object.nextLine();
            }
        }
        return nameList;
    }

    public static double[] getLabGrade(Scanner object) {
        double[] labGrade = new double[15];
        double[] labGradeSum = new double[15];
        int count = 0;
        object.nextLine();
        for (int i = 0; i < 15; i++) {
            labGrade[i] = object.nextDouble();
        }
        object.nextLine();
        object.nextLine();
        object.nextLine();
        object.nextLine();
        object.nextLine();
        object.nextLine(); 
    return labGrade ;
    }
}

【回答】

       数据每6行对应一条记录，要求对记录排序。其中final_exam_grade是单值，直接排序就行，lab grades是集合，要求平均后再排序。类似的结构化计算用JAVA编码复杂度很大。可以用SPL完成，再嵌入Java（参考Java 如何调用 SPL 脚本）：

A1：读取文本文件data.txt中的内容。

A2：提取：后边的数据。

A3：每6行数据分成一组，并创建以为name、lab_grades和final_exam_grade为列的序表，其中lab_grades列的成员为序列。

A4：结果按照final_exam_grade升序排列。

A5：结果按照lab_grades平均值降序排列。