如何让 Avro SchemaBuilder 在两个“记录”之间构建 map 的模式？

Question

Trying to serialize Java Objects represented as a Map. This requires me to build an Avro Schema first. I am using Avro SchemaBuilder for schema generation. Have already succeeded in schema generation for Map's objects. However can't deal with schema building for overall Map. Final schema should look like the following (created this one manually):

{
    "type": "record",
    "name": "MapObject",
    "namespace": "test",
    "fields": [
        {
            "name": "CacheMap",
            "type": {
                "type": "map",
                "values": [
                    {
                        "type": "record",
                        "name": "User",
                        "namespace": "test",
                        "fields": [                         
                            {
                                "name": "id",
                                "type": "long"
                            },
                            {
                                "name": "status",
                                "type": "string"
                            }
                        ]
                    },
                    {
                        "type": "record",
                        "name": "UserKey",
                        "namespace": "test",
                        "fields": [
                            {
                                "name": "key",
                                "type": "long"
                            },
                            {
                                "name": "keyPrint",
                                "type": "string"
                            }
                        ]
                    }
                ]
            }
        }
    ]
}

How can I pass to different records for key and value of a map in SchemaBuilder? SchemaBuilder.map().values() does not allow to pass more than one Schema as a parameter for .value() .

Answer 1

Apache Avro Unions can be of help here.

SchemaBuilder.builder()
            .map()
 .values(SchemaBuilder.unionOf().type(firstSchema).and().type(secondSchema).endUnion());

where the firstSchema and the secondSchema are separate schemas already defined for required User and UserKey 'records' (considering the schema from question)