data:

{

"_id" : ObjectId("57bd128452cb261e9c676a13"),

"_class" : "com.hunterplus.server.position.red_dot.RedDot",

"positionId" : "576b47f4e698010f7c5da670",

"userId" : "5600c0d10cf21f8a9384543b",

"noticeId" : "57bd128252cb261e9c676a12",

"type" : NumberInt(1)

}

{

"_id" : ObjectId("57bd128b52cb261e9c676a15"),

"_class" : "com.hunterplus.server.position.red_dot.RedDot",

"positionId" : "576b47f4e698010f7c5da670",

"userId" : "5600c0d10cf21f8a9384543b",

"noticeId" : "57bd128b52cb261e9c676a14",

"type" : NumberInt(1)

}

{

"_id" : ObjectId("57bd12d752cb260abc53127e"),

"_class" : "com.hunterplus.server.position.red_dot.RedDot",

"positionId" : "576b47f4e698010f7c5da672",

"userId" : "5600c0d10cf21f8a9384543b",

"noticeId" : "57bd128b52cb261e9c676a14",

"type" : NumberInt(1)

}

{

"_id" : ObjectId("57bd39fc52cb261a0c4462cc"),

"_class" : "com.hunterplus.server.position.red_dot.RedDot",

"positionId" : "576b47f4e698010f7c5da670",

"userId" : "5600c0d10cf21f8a9384543b",

"noticeId" : "57bd39fa52cb261a0c4462cb",

"type" : NumberInt(1)

}

Target dto:

public class  RedDotDto {

private  String  positionId;

private  List<String>  noticeIdList;

}

Aggregate 1:

Aggregation aggregation =newAggregation(

match(Criteria.where(RedDot.USER_ID).is(userId)),

project(RedDot.POSITION_ID,RedDot.NOTICE_ID).andExclude(Fields.UNDERSCORE_ID),

group(Fields.UNDERSCORE_ID,RedDot.POSITION_ID).push(RedDot.NOTICE_ID).as(RedDotDto.NOTICE_ID_LIST)

);

result 1 :

返回的数据带有positionId

Aggregate 2

Aggregation aggregation =newAggregation(

match(Criteria.where(RedDot.USER_ID).is(userId)),

project(RedDot.POSITION_ID,RedDot.NOTICE_ID),

group( RedDot.POSITION_ID).push(RedDot.NOTICE_ID).as(RedDotDto.NOTICE_ID_LIST)

);

result 2:

positionId  ： null