How to translate a mongodb aggregate query to Spring

I'm trying to translate this Mongo query to Spring:

db.doc.aggregate([
    {
        $match:{
            $and :[

                {"event_name":"event"},
                {"event_data.partnerName": { "$nin" : ["something"]}},
                {"event_time": {$gte : ISODate("2021-01-01T00:00:00Z")}},
                {"event_time": {$lte : ISODate("2021-12-31T24:00:00Z")}}
            ]}
    },
    {
        $project: {
            partner: "$eveny.name",
            month: {
                $substr: ["$event_time", 0, 4]
            }
        }
    },
    {
        $group: {
            _id: {"partner": "$partner", "month": "$month"},
            "Transactions": {$sum: 1}
        }
    },
    {
        $sort:{"_id.month":1}
    }
]);

I have been using the Aggregation library with MatchOperations and etc. but I'm still having a hard time translating $project and $group.