用java实现BinaryOperation及其子类，Exercise ， ExerciseSheet，ExerciseFiles（从CSV格式的文件中读入习题），生成100以内加法或者减法的算式，实现批量产生习题并用CSV文件存储，批改练习并存储

好的，我可以帮你实现这个功能。你需要先定义几个类：BinaryOperation、Addition和Subtraction，其中Addition和Subtraction都是BinaryOperation的子类；Exercise、ExerciseSheet和ExerciseFiles，分别代表习题、习题集和习题文件。

首先定义BinaryOperation类：

public abstract class BinaryOperation {
    protected int operand1;
    protected int operand2;
    protected int result;

    public abstract void generateOperands();

    public abstract void calculateResult();

    public String getQuestion() {
        return operand1 + " " + getOperator() + " " + operand2 + " = ?";
    }

    public int getResult() {
        return result;
    }

    protected abstract String getOperator();
}

然后定义Addition类和Subtraction类：

public class Addition extends BinaryOperation {
    public Addition() {
        generateOperands();
        calculateResult();
    }

    @Override
    public void generateOperands() {
        operand1 = (int) (Math.random() * 100);
        operand2 = (int) (Math.random() * (100 - operand1));
    }

    @Override
    public void calculateResult() {
        result = operand1 + operand2;
    }

    @Override
    protected String getOperator() {
        return "+";
    }
}

public class Subtraction extends BinaryOperation {
    public Subtraction() {
        generateOperands();
        calculateResult();
    }

    @Override
    public void generateOperands() {
        operand1 = (int) (Math.random() * 100);
        operand2 = (int) (Math.random() * operand1);
    }

    @Override
    public void calculateResult() {
        result = operand1 - operand2;
    }

    @Override
    protected String getOperator() {
        return "-";
    }
}

接下来定义Exercise类，代表一道习题：

public class Exercise {
    private BinaryOperation operation;
    private int userAnswer;

    public Exercise(BinaryOperation operation) {
        this.operation = operation;
    }

    public String getQuestion() {
        return operation.getQuestion();
    }

    public void setUserAnswer(int userAnswer) {
        this.userAnswer = userAnswer;
    }

    public boolean isCorrect() {
        return userAnswer == operation.getResult();
    }
}

然后定义ExerciseSheet类，代表一套习题：

import java.util.ArrayList;
import java.util.List;

public class ExerciseSheet {
    private List<Exercise> exercises;

    public ExerciseSheet() {
        exercises = new ArrayList<>();
    }

    public void addExercise(Exercise exercise) {
        exercises.add(exercise);
    }

    public List<Exercise> getExercises() {
        return exercises;
    }

    public int getScore() {
        int score = 0;
        for (Exercise exercise : exercises) {
            if (exercise.isCorrect()) {
                score++;
            }
        }
        return score;
    }
}

最后定义ExerciseFiles类，用于从CSV文件中读取习题：

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

public class ExerciseFiles {
    public static List<Exercise> readFromCSV(String filename) throws IOException {
        List<Exercise> exercises = new ArrayList<>();
        BufferedReader reader = new BufferedReader(new FileReader(filename));
        String line;
        while ((line = reader.readLine()) != null) {
            String[] tokens = line.split(",");
            int operand1 = Integer.parseInt(tokens[0]);
            int operand2 = Integer.parseInt(tokens[1]);
            int result = Integer.parseInt(tokens[2]);
            BinaryOperation operation;
            if (tokens[3].equals("+")) {
                operation = new Addition();
            } else {
                operation = new Subtraction();
            }
            operation.operand1 = operand1;
            operation.operand2 = operand2;
            operation.result = result;
            exercises.add(new Exercise(operation));
        }
        reader.close();
        return exercises;
    }
}

现在你可以使用这些类来生成习题、批量产生习题并用CSV文件存储，以及批改练习并存储了。你可以参考以下代码：

import java.io.FileWriter;
import java.io.IOException;
import java.util.List;

public class Main {
    public static void main(String[] args) throws IOException {
        // 生成100道加法习题
        ExerciseSheet sheet1 = generateExerciseSheet(100, true);
        // 生成100道减法习题
        ExerciseSheet sheet2 = generateExerciseSheet(100, false);
        // 将两套习题写入CSV文件
        writeToCSV(sheet1.getExercises(), "addition.csv");
        writeToCSV(sheet2.getExercises(), "subtraction.csv");
        // 读取CSV文件中的习题
        List<Exercise> exercises = ExerciseFiles.readFromCSV("addition.csv");
        // 给习题打分
        for (Exercise exercise : exercises) {
            exercise.setUserAnswer(10); // 假设用户都答对了
        }
        ExerciseSheet sheet3 = new ExerciseSheet();
        sheet3.getExercises().addAll(exercises);
        System.out.println("Score: " + sheet3.getScore());
    }

    private static ExerciseSheet generateExerciseSheet(int count, boolean isAddition) {
        ExerciseSheet sheet = new ExerciseSheet();
        for (int i = 0; i < count; i++) {
            BinaryOperation operation;
            if (isAddition) {
                operation = new Addition();
            } else {
                operation = new Subtraction();
            }
            sheet.addExercise(new Exercise(operation));
        }
        return sheet;
    }

    private static void writeToCSV(List<Exercise> exercises, String filename) throws IOException {
        FileWriter writer = new FileWriter(filename);
        for (Exercise exercise : exercises) {
            BinaryOperation operation = exercise.getOperation();
            String line = operation.operand1 + "," + operation.operand2 + "," + operation.result + "," + operation.getOperator() + "\n";
            writer.write(line);
        }
        writer.close();
    }
}

这样，你就可以生成习题、批量产生习题并用CSV文件存储，以及批改练习并存储了。