您可以通过组合通配符查询和范围查询来实现结果：

{
  "query": {
    "bool": {
      "must": [
        {
          "wildcard": {
            "test.keyword": "[A-Z]?*"
          }
        },
        {
          "range": {
            "test": {
              "gte": 203,
              "lte": 899
            }
          }
        }
      ]
    }
  }
}

在Java SDK中使用：

public class ElasticsearchQueryExample {
    public static void main(String[] args) {
        try (RestHighLevelClient client = new RestHighLevelClient(/* YOUR ELASTIC CLIENT */)) {

            SearchRequest searchRequest = new SearchRequest("your_index_name");
            
            BoolQueryBuilder boolQuery = QueryBuilders.boolQuery();

            // create the wildcard query
            WildcardQueryBuilder wildcardQuery = QueryBuilders.wildcardQuery("test.keyword", "[A-Z]?*");
            boolQuery.must(wildcardQuery);

            // create the range query
            RangeQueryBuilder rangeQuery = QueryBuilders.rangeQuery("test").gte(203).lte(899);
            boolQuery.must(rangeQuery);

            // add the query
            SearchSourceBuilder sourceBuilder = new SearchSourceBuilder();
            sourceBuilder.query(boolQuery);
            searchRequest.source(sourceBuilder);

            // send the request
            SearchResponse searchResponse = client.search(searchRequest, RequestOptions.DEFAULT);

        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}