java操作 mongodb 进行 按天、周、月分组统计

	public List<PlaybackEntity> queryPlaybackRecord(FunctionUseQueryEntity queryEntity){
		Criteria criteria = Criteria.where("createTime").gte(queryEntity.getStartTime()).lte(queryEntity.getEndTime())
							.and("status").is(1);
		Query query = Query.query(criteria);	
		
        BasicDBObject initial = new BasicDBObject();
        initial.put("playbackNum", 0);
        
        String reduce = getReduce();
        //进行按天、周、月分组
        String keyf = getKeyf(queryEntity);
           
        DBCollection collection = mongoTemplate.getCollection(COLLNAME);
        
        GroupCommand xx = new GroupCommand(collection, keyf, query.getQueryObject(), initial, reduce, null);
 
        BasicDBList  objects =  (BasicDBList)collection.group(xx);
        
        List<PlaybackEntity> results = new ArrayList<PlaybackEntity>();
        if (objects != null) {
            for (int i = 0; i < objects.size(); i++) {
            	PlaybackEntity play = new PlaybackEntity();
                DBObject obj = (DBObject) objects.get(i);
                play.setFormateTime((String)obj.get("strData"));
                play.setPlaybackNum((Double)obj.get("playbackNum"));
                results.add(play);
            }
        }
		return results;
	}

	private String getKeyf(FunctionUseQueryEntity queryEntity) {
		StringBuilder keyfBuilder = new StringBuilder();
        keyfBuilder.append("function(doc){ ")
        			.append("    var date = new Date(doc.createTime); ");
        if(DateType.DATE.getValue().equals(queryEntity.getType())){
        	keyfBuilder.append("    var dateKey = '' + date.getFullYear()+ '-' + (date.getMonth()+1) + '-' + date.getDate();");
        }else if(DateType.WEEK.getValue().equals(queryEntity.getType())){
        	keyfBuilder.append("	var firstDay = new Date(date.getFullYear(),0, 1);")
        			   .append("    var dayOfWeek = firstDay.getDay();") 
        			   .append("    var spendDay= 1;") 
        			   .append("    if (dayOfWeek !=0) {") 
        			   .append("         spendDay= 7 - dayOfWeek + 1;") 
        			   .append("    }") 
        			   .append("    firstDay = new Date(date.getFullYear(), 0, 1 + spendDay);") 
        			   .append("    var d =Math.ceil((date.valueOf()- firstDay.valueOf())/ 86400000);") 
        			   .append("    var week =Math.ceil(d/7);") 
        			   .append("    week = week + 1;"); 
        	keyfBuilder.append("    var dateKey = '' + date.getFullYear()+ '-' + week;");
        }else if(DateType.MONTH.getValue().equals(queryEntity.getType())){
        	keyfBuilder.append("    var dateKey = '' + date.getFullYear()+ '-' + (date.getMonth()+1);");
        }
        keyfBuilder.append("    return {'strData':dateKey};  ")
        		   .append(" }");
		return keyfBuilder.toString();
	}

	private String getReduce() {
		StringBuilder reduceBuilder = new StringBuilder();
        reduceBuilder.append("function Reduce(doc, out) { ")
        			 .append("    out.playbackNum += 1; ")
        			 .append(" }");
		return reduceBuilder.toString();
	}