Add QuestionService

application/module-exercise/src/main/java/org/fuseri/moduleexercise/question/QuestionService.java

+package org.fuseri.moduleexercise.question;
+
+import jakarta.persistence.EntityNotFoundException;
+import lombok.Getter;
+import org.fuseri.moduleexercise.common.DomainService;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.data.domain.Page;
+import org.springframework.data.domain.PageRequest;
+import org.springframework.stereotype.Service;
+import org.springframework.transaction.annotation.Transactional;
+
+/**
+ * Represent a service for managing Question entities
+ */
+@Service
+public class QuestionService extends DomainService<Question> {
+
+    /**
+     * The repository instance used by this service
+     */
+    @Getter
+    private final QuestionRepository repository;
+
+    /**
+     * Construct a new instance of QuestionService with the specified repository
+     *
+     * @param repository the repository instance to be used by this service
+     */
+    @Autowired
+    public QuestionService(QuestionRepository repository) {
+        this.repository = repository;
+    }
+
+    /**
+     * Retrieve the Question entity with the specified ID
+     *
+     * @param id the ID of the Question entity to retrieve
+     * @return the Question entity with the specified ID
+     * @throws EntityNotFoundException if no Question entity exists with the specified ID
+     */
+    @Transactional(readOnly = true)
+    public Question find(String id) {
+        return repository.findById(id)
+                .orElseThrow(() -> new EntityNotFoundException("Question '" + id + "' not found."));
+    }
+
+    /**
+     * Retrieve a page of Question entities associated with the specified exercise ID
+     *
+     * @param exerciseId the ID of the exercise to retrieve questions for
+     * @param page       the page number to retrieve (0-indexed)
+     * @return a page of Question entities associated with the specified exercise ID
+     */
+    @Transactional(readOnly = true)
+    public Page<Question> findByExerciseId(String exerciseId, int page) {
+        return repository.findByExerciseId(
+                exerciseId,
+                PageRequest.of(page, DomainService.DEFAULT_PAGE_SIZE));
+    }
+
+}