JSON with script and aggregation Query to Java REST High or Low Level Client

[rakotomandimby (Mihamina Rakotomandimby)]

Hi all,
I'm querying ES 7.3 from the Java REST High Level Client.
For "simple" queries, I have always been able to transcript them to Java, but this time, I face the problem.
This is the JSON query

{
    "query": {
        "bool": {
            "filter": {
                "script": {
                    "script": {
                        "source": "(doc['mois'].value.getYear()==2019) && (doc['mois'].value.getMonthValue()==4)",
                        "lang": "painless"
                    }
                }
            },
            "must": {
                "bool": {
                    "should": [
                        {"term" : {"numid": 51237}},
                        {"term" : {"numid": 13798}},
                        {"term" : {"numid": 10764}},
                        {"term" : {"numid": 12909}},
                        {"term" : {"numid": 12445}},
                        {"term" : {"numid": 12946}},
                        {"term" : {"numid": 13007}}                     
                    ]
                }
            }
            
        }
    },
    "aggs": {
        "sum_download": {
            "sum": {
                "script": {
                    "source": "doc['download']"
                }
            }
        },
        "sum_upload": {
            "sum": {
                "script": {
                    "source": "doc['upload']"
                }
            }
        }
    }
}

The bool / must / should queries are what I'm able to transcript to Java.
But the script / aggs ones... are harder.

Have you got any kind of tutorial for that use case of transcripting this to Java REST High or Low Level Client?

Thank you.