java 中 mongodb的各种操作

转自：http://www.cnblogs.com/ry123/p/3863155.html

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:

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);    }

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

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);    }

 

 

5. 查询数量:

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);    }

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);        }    }