jiedui/src/service/QuestionService.java

package service;

import model.Question;
import java.util.*;

public class QuestionService {
  /*生成试卷的题目部分*/
  public List<Question> generateQuestions(String difficulty, int count) {
    if(count < 10 || count > 30) {
      return null;
    }
    
    List<Question> questions = new ArrayList<>();
    Set<String> usedQuestions = new HashSet<>();
    QuestionGenerator generator = QuestionGeneratorFactory.getGenerator(difficulty);
    
    while (questions.size() < count) {
      Question q = generator.generateQuestion();
      if (usedQuestions.add(q.getContent())) {
        questions.add(q);
      }
    }
    return questions;
  }
}