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Sharing various examples of mongodb operation query in Java

黄舟
Release: 2017-09-25 10:38:16
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这篇文章主要介绍了java 中mongodb的各种操作查询的实例详解的相关资料,希望通过本文能帮助到大家,需要的朋友可以参考下

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); 
    }
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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);     
    }
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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); 
    }
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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); 
   }
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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); 
    }
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查询字段不为空的数据 -----关键字---ne


  Criteria.where("key1").ne("").ne(null)
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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));
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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);
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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("{&#39;key2.keyA&#39;:?0}") 
  List<Asset> findAllBykeyA(String keyA);
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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); 
    }
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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);
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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); 
    }
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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); 
    }
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8. 删除数据:


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