java 中mongodb的各种操作查询的实例详解

java 中mongodb的各种操作查询的实例详解

一. 常用查询:

1. 查询一条数据:(多用于保存时判断db中是否已有当前数据,这里 is  精确匹配,模糊匹配 使用regex...)

  public PageUrl getByUrl(String url) {
      return findOne(new Query(Criteria.where("url").is(url)),PageUrl.class);
    }

2. 查询多条数据:linkUrl.id 属于分级查询

  public List<PageUrl> getPageUrlsByUrl(int begin, int end,String linkUrlid) {
      Query query = new Query();
      query.addCriteria(Criteria.where("linkUrl.id").is(linkUrlid));
      return find(query.limit(end - begin).skip(begin), PageUrl.class);
    }

3.模糊查询:-----关键字---regex

 public long getProcessLandLogsCount(List<Condition> conditions)
    {
      Query query = new Query();
      if (conditions != null && conditions.size() > 0) {
        for (Condition condition : conditions) {
          query.addCriteria(Criteria.where(condition.getKey()).regex(".*?\\" +condition.getValue().toString()+ ".*"));
        }
      }
      return count(query, ProcessLandLog.class);
    }

最下面，我在代码亲自实践过的模糊查询，只支持字段属性是字符串的查询，你要是查字段属性是int的模糊查询，还真没辙。

4.gte: 大于等于,lte小于等于...注意查询的时候各个字段的类型要和mongodb中数据类型一致

 public List<ProcessLandLog> getProcessLandLogs(int begin,int end,List<Condition> conditions,String orderField,Direction direction)
    {
      Query query = new Query();
      if (conditions != null && conditions.size() > 0) {
        for (Condition condition : conditions) {
          if(condition.getKey().equals("time")){
            query.addCriteria(Criteria.where("time").gte(condition.getValue())); //gte: 大于等于
          }else if(condition.getKey().equals("insertTime")){
            query.addCriteria(Criteria.where("insertTime").gte(condition.getValue()));
          }else{
            query.addCriteria(Criteria.where(condition.getKey()).is(condition.getValue()));
          }
        }
      }
      return find(query.limit(end - begin).skip(begin).with(new Sort(new Sort.Order(direction, orderField))), ProcessLandLog.class);
    } 

  public List<DpsLand> getDpsLandsByTime(int begin, int end, Date beginDate,Date endDate) {
   return find(new Query(Criteria.where("updateTime").gte(beginDate).lte(endDate)).limit(end - begin).skip(begin),
    DpsLand.class);
   }

查询字段不存在的数据 -----关键字---not

public List<GoodsDetail> getGoodsDetails2(int begin, int end) {
      Query query = new Query();
      query.addCriteria(Criteria.where("goodsSummary").not());
      return find(query.limit(end - begin).skip(begin),GoodsDetail.class);
    }

查询字段不为空的数据     -----关键字---ne

  Criteria.where("key1").ne("").ne(null)

查询或语句：a || b     ----- 关键字---orOperator

 Criteria criteria = new Criteria();
  criteria.orOperator(Criteria.where("key1").is("0"),Criteria.where("key1").is(null));

查询且语句：a && b     ----- 关键字---and

  Criteria criteria = new Criteria();
  criteria.and("key1").is(false);
  criteria.and("key2").is(type);
  Query query = new Query(criteria);
  long totalCount = this.mongoTemplate.count(query, Xxx.class);

查询一个属性的子属性，例如：查下面数据的key2.keyA的语句

  var s = {
      key1: value1,
      key2: {
        keyA: valueA,
        keyB: valueB
      }
    }; 

  @Query("{'key2.keyA':?0}")
  List<Asset> findAllBykeyA(String keyA);

5. 查询数量:----- 关键字---count

 public long getPageInfosCount(List<Condition> conditions) {
      Query query = new Query();
      if (conditions != null && conditions.size() > 0) {
        for (Condition condition : conditions) {
          query.addCriteria(Criteria.where(condition.getKey()).is(condition.getValue()));
        }
      }
      return count(query, PageInfo.class);
    }

查找包含在某个集合范围：----- 关键字---in

  Criteria criteria = new Criteria();
  Object [] o = new Object[]{0, 1, 2}; //包含所有
  criteria.and("type").in(o);
  Query query = new Query(criteria);
  query.with(new Sort(new Sort.Order(Direction.ASC, "type"))).with(new Sort(new Sort.Order(Direction.ASC, "title")));
  List<WidgetMonitor> list = this.mongoTemplate.find(query, WidgetMonitor.class);

6. 更新一条数据的一个字段:

  public WriteResult updateTime(PageUrl pageUrl) {
      String id = pageUrl.getId();
      return updateFirst(new Query(Criteria.where("id").is(id)),Update.update("updateTime", pageUrl.getUpdateTime()), PageUrl.class);
    }

7. 更新一条数据的多个字段:

  //调用更新
  private void updateProcessLandLog(ProcessLandLog processLandLog,
        int crawlResult) {
      List<String> fields = new ArrayList<String>();
      List<Object> values = new ArrayList<Object>();
      fields.add("state");
      fields.add("result");
      fields.add("time");
      values.add("1");
      values.add(crawlResult);
      values.add(Calendar.getInstance().getTime());
      processLandLogReposity.updateProcessLandLog(processLandLog, fields,
          values);
    }
  //更新
  public void updateProcessLandLog(ProcessLandLog land, List<String> fields,List<Object> values) {
      Update update = new Update();
      int size = fields.size();
      for(int i = 0 ; i < size; i++){
        String field = fields.get(i);
        Object value = values.get(i);
        update.set(field, value);
      }
      updateFirst(new Query(Criteria.where("id").is(land.getId())), update,ProcessLandLog.class);
    }

8. 删除数据:

  public void deleteObject(Class<T> clazz,String id) {
      remove(new Query(Criteria.where("id").is(id)),clazz);
    }

9.保存数据:

//插入一条数据
  public void saveObject(Object obj) {
      insert(obj);
    } 

  //插入多条数据
  public void saveObjects(List<T> objects) {
      for(T t:objects){
        insert(t);
      }
    }

我自己使用的例子：

下面例子涉及到：

精确查询：is；

模糊查询：regex；

分页查询，每页多少：skip，limit

按某个字段排序(或升或降)：new Sort(new Sort.Order(Sort.Direction.ASC, "port"))

查询数量：count

  public Map<String, Object> getAppPortDetailByPage(int pageNo, int pageSize, String order, String sortBy, String appPortType, String appPortSeacherName) {
    Criteria criteria = new Criteria();
    if (!appPortType.equals("")) {
      if (!appPortType.equals("all")) {
        //DB表里的字段----appmanageType
        //下同 port protocol 也是DB表的字段
        criteria.and("appmanageType").is(appPortType);
      }
    }
    if (!appPortSeacherName.equals("")) {
      try {
        criteria.orOperator(Criteria.where("port").is(Integer.parseInt(appPortSeacherName)),
            Criteria.where("protocol").regex(".*?" + appPortSeacherName + ".*"));
      }catch (Exception e){
        criteria.orOperator(Criteria.where("protocol").regex(".*?" + appPortSeacherName + ".*"));
      }
    }
    Map<String, Object> result = Maps.newHashMap();
    Query query = new Query(criteria);
    query.skip((pageNo - 1) * pageSize);
    query.limit(pageSize);
    if(order != null && sortBy != null){
      query.with(new Sort(new Sort.Order(order.equals("asc") ? Sort.Direction.ASC : Sort.Direction.DESC, sortBy)));
    }else {
      query.with(new Sort(new Sort.Order(Sort.Direction.ASC, "port")));
    }
    List<Appportmanage> list = this.mongoTemplate.find(query, Appportmanage.class);
    long count = this.mongoTemplate.count(query, Appportmanage.class);
    result.put("datas", list);
    result.put("size", count);
    return result;
  }

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