目录 前言1、表及字段设计2、引入pom3、yml配置4、实体类创建5、Repository5.1、基础实现5.2、方法查询5.3、语句查询 6、具体实现0、创建Repository1、新增数据2、修改数据3、删除数据4、根据ID查询5、聚合查询6、列表分页+条件+排序查询 前言
使用SpringBoot+MongoDB整合实现文章评论的实例操作。
1、表及字段设计数据库名称：articledb
通过实现MongoRepository<T, ID>接口，创建Repository类，其中T表示实体类的class,ID表示主键的数据类型，比如：
public interface CommentRepository extends MongoRepository<Comment, String> {}在实现MongoRepository<T, ID>接口后，会默认实现以下接口：
<S extends T> List<S> saveAll(Iterable<S> var1); List<T> findAll(); List<T> findAll(Sort var1); <S extends T> S insert(S var1); <S extends T> List<S> insert(Iterable<S> var1); <S extends T> List<S> findAll(Example<S> var1); <S extends T> List<S> findAll(Example<S> var1, Sort var2); Optional<T> findById(ID var1); boolean existsById(ID var1); Iterable<T> findAll(); Iterable<T> findAllById(Iterable<ID> var1); long count(); void deleteById(ID var1); void delete(T var1); void deleteAll(Iterable<? extends T> var1); void deleteAll(); 5.2、方法查询除此之外也可以根据具体的方法名称进行查询相应内容，比如：findByName(String name)、findByNameAndUserId(String name,String userId)
5.3、语句查询通过@Query编写类似sql的查询语句，支持动态传入参数，比如：
@Query(value="{\"username\":{\"$regex\":?0},\"age\":{\"$gte\":?1,\"$lte\": ?2}}") Page<User> findByNameAndAgeRange(String name,int age,int ageTo,Pageable page); 6、具体实现 0、创建Repository public interface CommentRepository extends MongoRepository<Comment, String> { } 1、新增数据 @RestController @RequestMapping("mongo") @Slf4j public class CommentController { @Resource private CommentRepository commentRepository; @Resource private MongoTemplate mongoTemplate; @PostMapping public void saveComment(@RequestBody Comment comment) { int id = (int) (Math.random() * 10000000); int userId = (int) (Math.random() * 10); int articleId = (int) (Math.random() * 10); comment.setId(id + ""); comment.setReplyNum(articleId); comment.setLikeNum(userId); comment.setArticleId(articleId + ""); comment.setUserId(userId + ""); comment.setNickName("测试人员"); comment.setParentId("0"); comment.setState("1"); comment.setContent("测试内容"); comment.setCreateTime(System.currentTimeMillis()); commentRepository.save(comment); // 如果批量新增 List<Comment> list = new ArrayList<>(); for (int i = 0; i <= 2; i++) { Comment comment2 = new Comment(); BeanUtils.copyProperties(comment, comment2); int newId = (int) (Math.random() * 100000); int newUserId = (int) (Math.random() * 10); int newArticleId = (int) (Math.random() * 10); comment2.setId(newId + ""); comment2.setReplyNum(articleId); comment2.setLikeNum(userId); comment2.setArticleId(newArticleId + ""); comment2.setUserId(newUserId + ""); comment.setNickName("测试人员"); comment.setParentId("0"); comment.setState("1"); comment.setContent("测试内容"); comment2.setCreateTime(System.currentTimeMillis()); list.add(comment2); } commentRepository.saveAll(list); } } 2、修改数据 @RestController @RequestMapping("mongo") @Slf4j public class CommentController { @Resource private CommentRepository commentRepository; @Resource private MongoTemplate mongoTemplate; @PutMapping public void updateComment(@RequestBody Comment comment) { comment.setId("1847892"); comment.setNickName("测试人员-修改"); comment.setParentId("0"); comment.setState("1"); comment.setContent("测试内容"); comment.setCreateTime(System.currentTimeMillis()); // 使用save时，如果数据存在则更新，不存在则新增 commentRepository.save(comment); } } 3、删除数据 @RestController @RequestMapping("mongo") @Slf4j public class CommentController { @Resource private CommentRepository commentRepository; @Resource private MongoTemplate mongoTemplate; // 根据Id删除 @DeleteMapping("/{id}") public void deleteCommentById(@PathVariable("id") String id) { commentRepository.deleteById(id); } // 按条件删除 @DeleteMapping("/condition") public void deleteCommentByArticleId() { // 删除articleId为10的数据 Query query = new Query(Criteria.where("articleId").is("10")); mongoTemplate.remove(query, Comment.class); } } 4、根据ID查询 @RestController @RequestMapping("mongo") @Slf4j public class CommentController { @Resource private CommentRepository commentRepository; @Resource private MongoTemplate mongoTemplate; @GetMapping("/{id}") public Object findCommentById(@PathVariable("id") String id) { /** * mongoTemplate实现 * Query query = new Query(Criteria.where("_id").is(id)); * mongoTemplate.remove(query, Comment.class); */ return commentRepository.findById(id); } } 5、聚合查询 @RestController @RequestMapping("mongo") @Slf4j public class CommentController { @Resource private CommentRepository commentRepository; @Resource private MongoTemplate mongoTemplate; @GetMapping("/agg") public ResponseObject agg() { // 1、单/多字段分组 - 分页排序 Aggregation aggregation = Aggregation.newAggregation( Aggregation.group("userId", "articleId").count().as("userNum"), Aggregation.skip(1L), Aggregation.limit(10), Aggregation.sort(Sort.Direction.DESC, "userNum") ); AggregationResults<BasicDBObject> basicDBObjects = mongoTemplate.aggregate(aggregation, Comment.class, BasicDBObject.class); System.out.println("basicDBObjects:"); for (DBObject obj : basicDBObjects) { System.out.println(obj); } // 2、条件匹配分组，$match表示匹配条件，在group前表示where，在后表示having，userid为分组字段 // select userid, count(*) as num from comment where articleId in(4,5) likeNum >= 1 and likeNum =<10 group by userid having num >=2 Aggregation aggregation2 = Aggregation.newAggregation( Aggregation.match(Criteria.where("likeNum").gte(1).lte(10).and("articleId").in("4", "5")), Aggregation.group("userId").count().as("userNum"), Aggregation.match(Criteria.where("userNum").gte(2)) ); AggregationResults<BasicDBObject> basicDBObjects2 = mongoTemplate.aggregate(aggregation2, Comment.class, BasicDBObject.class); System.out.println("basicDBObjects2:"); for (DBObject obj : basicDBObjects2) { System.out.println(obj); } // 3、聚合-求某个数值平均值、最大值、最小值 Aggregation aggregation3 = Aggregation.newAggregation( Aggregation.match(Criteria.where("likeNum").gte(1).lte(10)), Aggregation.group("userId").sum("likeNum").as("likeNumSum") .avg("likeNum").as("likeNumAvg") // Aggregation.match(Criteria.where("userNum").gte(2)) ); AggregationResults<BasicDBObject> basicDBObjects3 = mongoTemplate.aggregate(aggregation3, Comment.class, BasicDBObject.class); System.out.println("basicDBObjects3:"); for (DBObject obj : basicDBObjects3) { System.out.println(obj); } // 4、聚合分组数组 ,等同于group_concat，push-元素可重复，addToSet-元素不可重复 Aggregation aggregation4 = Aggregation.newAggregation( Aggregation.group("userId") .addToSet("articleId").as("setList") .push("articleId").as("pushList") ); AggregationResults<BasicDBObject> basicDBObjects4 = mongoTemplate.aggregate(aggregation4, Comment.class, BasicDBObject.class); System.out.println("basicDBObjects4:"); for (DBObject obj : basicDBObjects4) { System.out.println(obj); } } } 6、列表分页+条件+排序查询为了实现统一的分页查询，封装分页工具类：PageBuilder、NewPageBean，代码如下： PageBuilder：
import org.springframework.data.mongodb.core.query.Query; public class PageBuilder { /** * @param query 查询 * @param pageSize 当前页数 * @param pageNum 当前页码 */ public static void startPage(Query query, Integer pageSize, Integer pageNum) { if (pageSize == null || pageNum == null) { pageSize = 10; pageNum = 1; } int offset = (pageNum - 1) * pageSize; query.skip(offset).limit(pageSize); } }NewPageBean：
import com.lhz.search.model.param.PageParam; import org.springframework.data.mongodb.core.MongoTemplate; import org.springframework.data.mongodb.core.query.Query; import java.util.List; public class NewPageBean<T> { private Long total; private List<T> list; private MyPage pageInfo; public NewPageBean(List<T> list, Class<?> entityClass, PageParam param, MongoTemplate mongoTemplate) { Integer pageNum = param.getPageNum(); Integer pageSize = param.getPageSize(); long totalSize = mongoTemplate.count(new Query(), entityClass); //计算总页数 long totalPage = totalSize % pageSize == 0 ? totalSize / pageSize : totalSize / pageSize + 1; // 数据组装 this.list = list; this.total = totalSize; MyPage page = new MyPage(); page.setTotalPage(totalPage); page.setPageNum(pageNum); page.setPageSize(pageSize); page.setPreviousPage(pageNum - 1); page.setNextPage(pageNum + 1); this.pageInfo = page; } public long getNum() { return this.total; } public void setNum(Long total) { this.total = total; } public Long getTotal() { return total; } public void setTotal(Long total) { this.total = total; } public List<T> getList() { return list; } public void setList(List<T> list) { this.list = list; } public MyPage getPageInfo() { return pageInfo; } public void setPageInfo(MyPage pageInfo) { this.pageInfo = pageInfo; } class MyPage { private int pageNum; private int pageSize; private long totalPage; private int nextPage; private int previousPage; public int getPageNum() { return pageNum; } public void setPageNum(int pageNum) { this.pageNum = pageNum; } public int getPageSize() { return pageSize; } public void setPageSize(int pageSize) { this.pageSize = pageSize; } public long getTotalPage() { return totalPage; } public void setTotalPage(long totalPage) { this.totalPage = totalPage; } public int getNextPage() { return nextPage; } public void setNextPage(int nextPage) { this.nextPage = nextPage; } public int getPreviousPage() { return previousPage; } public void setPreviousPage(int previousPage) { this.previousPage = previousPage; } } }查询参数-CommentParam：
@Data public class CommentParam extends PageParam implements Serializable { /** * 文章ID */ private String articleId; /** * 用户Id */ private String userId; /** * 关键字 */ private String keyWord; /** * 昵称(模糊查询) */ private String nickName; /** * 开始时间 */ private Long startTime; /** * 结束时间 */ private Long endTime; }Controller：
@RestController @RequestMapping("mongo") @Slf4j public class CommentController { @Resource private CommentRepository commentRepository; @Resource private MongoTemplate mongoTemplate; @GetMapping public Object findCommentList(CommentParam param) { // 如果只是单一条件 // Query query = new Query(Criteria.where("nickName").is("查询内容")); // List<Comment> comment = mongoTemplate.find(query, Comment.class); // Comment one = mongoTemplate.findOne(query, Comment.class); // 多条件匹配，复杂查询 Criteria criteria = new Criteria(); if (param.getArticleId() != null) { criteria.and("articleId").is(param.getArticleId()); } if (param.getUserId() != null) { criteria.and("userId").is(param.getUserId()); } if (param.getNickName() != null) { //模糊匹配 //右匹配 // Pattern pattern = Pattern.compile("^.*"+param.getKeyWord()+"$", Pattern.CASE_INSENSITIVE); //左匹配 // Pattern pattern = Pattern.compile("^"+param.getKeyWord()+".*$", Pattern.CASE_INSENSITIVE); Pattern pattern = Pattern.compile("^.*" + param.getNickName() + ".*$", Pattern.CASE_INSENSITIVE); criteria.and("nickName").regex(pattern); } if (param.getKeyWord() != null) { //模糊匹配 - 或查询 Pattern pattern = Pattern.compile("^.*" + param.getKeyWord() + ".*$", Pattern.CASE_INSENSITIVE); criteria.orOperator(Criteria.where("nickName").regex(pattern), Criteria.where("content").regex(pattern)); } if (param.getEndTime() != null && param.getStartTime() != null) { criteria.andOperator(Criteria.where("createTime").gte(param.getStartTime()), Criteria.where("createTime").lte(param.getEndTime())); } Query query = new Query(); // 添加查询条件 query.addCriteria(criteria); // 排序-时间降序，userId生效 query.with(Sort.by(Sort.Order.desc("createTime"), Sort.Order.asc("userId"))); // 分页 PageBuilder.startPage(query, param.getPageSize(), param.getPageNum()); // 查询 List<Comment> list = mongoTemplate.find(query, Comment.class); // 分页参数封装 return new NewPageBean<>(list, Comment.class, param, mongoTemplate); } }
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