update

src/main/java/com/yaoyuan/jiscuss/service/impl/DiscussionsServiceImpl.java

@@ -10,54 +10,49 @@ import org.springframework.data.domain.PageRequest;
 import org.springframework.data.domain.Pageable;
 import org.springframework.data.domain.Sort;
 import org.springframework.stereotype.Service;
+import org.springframework.transaction.annotation.Transactional;
 
-import javax.transaction.Transactional;
 import java.util.List;
 
 @Service
-@Transactional
 public class DiscussionsServiceImpl implements IDiscussionsService {
+
     @Autowired
     private DiscussionsRepository discussionsRepository;
 
+    @Transactional(readOnly = true)
     @Override
     public List<Discussion> getAllList() {
         return discussionsRepository.findAll();
     }
 
+    @Transactional
     @Override
     public Discussion insert(Discussion discussion) {
-
         return discussionsRepository.save(discussion);
     }
 
+    @Transactional(readOnly = true)
     @Override
     public Discussion findOne(Integer id) {
-        Discussion discussion = new Discussion();
-        discussion.setId(id);
-        return discussionsRepository.getOne(id);
+        // getReferenceById replaces removed JpaRepository.getOne()
+        return discussionsRepository.getReferenceById(id);
     }
 
+    @Transactional(readOnly = true)
     @Override
     public Page<Discussion> queryAllDiscussionsList(Discussion discussion, int pageNum, int pageSize, String tag, String type) {
-        Sort sort = new Sort(Sort.Direction.DESC, "id");
-        if (type.equals("hot")) {
-            sort = new Sort(Sort.Direction.DESC, "likeCount");
-        } else if (type.equals("new")) {
-            sort = new Sort(Sort.Direction.DESC, "startTime");
-        }
-        @SuppressWarnings("deprecation")
-        Pageable pageable = new PageRequest(pageNum, pageSize, sort);
-        //将匹配对象封装成Example对象
+        Sort sort = switch (type) {
+            case "hot" -> Sort.by(Sort.Direction.DESC, "likeCount");
+            case "new" -> Sort.by(Sort.Direction.DESC, "startTime");
+            default    -> Sort.by(Sort.Direction.DESC, "id");
+        };
+        Pageable pageable = PageRequest.of(pageNum, pageSize, sort);
         Example<Discussion> example = Example.of(discussion);
-        if (null != tag && !"all".equals(tag)) {
-            Page<Discussion> pageList = discussionsRepository.findByQuery(tag, pageable);
-            return pageList;
+        if (tag != null && !"all".equals(tag)) {
+            return discussionsRepository.findByQuery(tag, pageable);
         } else {
-            Page<Discussion> pageList = discussionsRepository.findAll(example, pageable);
-            return pageList;
+            return discussionsRepository.findAll(example, pageable);
         }
-
-
     }
 }