一、 需求
設(shè)計(jì)一個(gè)網(wǎng)站評(píng)論的數(shù)據(jù)庫表設(shè)計(jì)，實(shí)現(xiàn)的功能如下

• 對(duì)于一個(gè)問題的主評(píng)論
• 對(duì)于一個(gè)評(píng)論的子評(píng)論

二、 設(shè)計(jì)

三、 實(shí)現(xiàn)

1. 技術(shù)選型

   1. mongodb-driver
      是mongo官方推出的java連接mongodb的驅(qū)動(dòng)包，相當(dāng)于JDBC驅(qū)動(dòng)

   2. SpringDataMongoDb
      springData家族成員之一，用于操作MongoDb的持久層框架，封裝了底層的mongodb-driver

2. pom依賴

  <!-- https://mvnrepository.com/artifact/org.springframework.data/spring-data-mongodb -->
        <dependency>
            <groupId>org.springframework.data</groupId>
            <artifactId>spring-data-mongodb</artifactId>
            <version>2.2.0.RELEASE</version>
        </dependency>

3. 文件配置

<!-- application.properties -->
spring.data.mongodb.uri=mongodb://127.0.0.1:27017/articaledb

4. 項(xiàng)目核心代碼

   1. dao層

       public interface CommentRepository extends MongoRepository<Comment, String> {}
      

   2. service層

      1. 接口

      public interface CommentService {
      List<Comment> saveAll(Iterable<Comment> var1);
      
      List<Comment> findAll();
      
      List<Comment> findAll(Sort var1);
      
      Comment insert(Comment var1);
      
      List<Comment> insert(Iterable<Comment> var1);
      
      List<Comment> findAll(Example<Comment> var1);
      
      List<Comment> findAll(Example<Comment> var1, Sort var2);
      Page<Comment> findByParentId(String parentId, int page, int size);
      void update(String id);
      }
      

      2. 實(shí)現(xiàn)類

      @Service
      public class CommentServiceImpl implements CommentService {
      @Autowired
       CommentRepository commentRepository;
       @Autowired
      MongoTemplate mongoTemplate;
      
      
      
      
      @Override
       public List<Comment> saveAll(Iterable<Comment> var1) {
          return commentRepository.saveAll(var1);
       }
      
        @Override
        public List<Comment> findAll() {
           return commentRepository.findAll();
        }
      
       @Override
        public List<Comment> findAll(Sort var1) {
           return commentRepository.findAll(var1);
       }
      
        @Override
       public Comment insert(Comment var1) {
           return commentRepository.insert(var1);
        }
      
        @Override
        public List<Comment> insert(Iterable<Comment> var1) {
            return commentRepository.insert(var1);
        }
      
       @Override
        public List<Comment> findAll(Example<Comment> var1) {
            return commentRepository.findAll(var1);
        }
      
        @Override
        public List<Comment> findAll(Example<Comment> var1, Sort var2) {
            return commentRepository.findAll(var1, var2);
       }
        @Override
        public Page<Comment> findByParentId(String parentId, int page, int size) {
            return commentRepository.findByParentId(parentId, PageRequest.of(page-1,size));
        }
        @Override
        public void update(String id) {
          Query query = Query.query(Criteria.where("_id").is(id));
          Update update = new Update();
          update.inc("likeNum");
          mongoTemplate.updateFirst(query, update, "comment");
      }
      }
      
       
      

   3. 測(cè)試類

   @SpringBootTest
   @RunWith(SpringRunner.class)  
   class CommentServiceImplTest {
     @Autowired
     CommentService commentService;
     /**
     查詢?nèi)?  **/
   
     @Test
     void findAll() {
         List<Comment> comments = commentService.findAll();
         System.out.println(comments);
     }
     /**
     保存
     **/
     @Test
     void insert() {
     Comment comment = new Comment();
     comment.setContent("這是一條評(píng)論");
     comment.setPublishDate(new Date());
     comment.setUserId("1");
     comment.setUserName("馬");
     comment.setCreateDatetime(LocalDateTime.now());
     comment.setLikeNum(100);
     comment.setReplyNum(100);
     comment.setState("1");
     comment.setArticaleId("25");
     commentService.insert(comment);
     }
     @Test
     void findByParentId() {
     commentService.findByParentId("3", 1, 2);
     }
    @Test
     void update() {
     String id="1";
     commentService.update(id);
     }
   }