建议查询功能实现

[tianxia0079]

以下是7版本的代码，可是换成8网上找不到最新版本的教程。麻烦实现参考以下。谢谢

public class ElasticsearchClient {

    private static final String INDEX_NAME = "my_index";
    private static final String FIELD_NAME = "suggestion_field";
    private RestHighLevelClient client;

    public ElasticsearchClient(String hostname, int port) {
        client = new RestHighLevelClient(
            RestClient.builder(new HttpHost(hostname, port, "http")));
    }

    public List<String> getSuggestions(String input) throws IOException {
        SearchRequest searchRequest = new SearchRequest(INDEX_NAME);
        SearchSourceBuilder searchSourceBuilder = new SearchSourceBuilder();

        CompletionSuggestionBuilder completionSuggestionBuilder = new CompletionSuggestionBuilder(FIELD_NAME);
        completionSuggestionBuilder.prefix(input);
        completionSuggestionBuilder.size(5); // Limit the number of suggestions

        SuggestBuilder suggestBuilder = new SuggestBuilder();
        suggestBuilder.addSuggestion("suggest", completionSuggestionBuilder);
        searchSourceBuilder.suggest(suggestBuilder);

        searchRequest.source(searchSourceBuilder);
        SearchResponse searchResponse = client.search(searchRequest, RequestOptions.DEFAULT);

        Suggest suggest = searchResponse.getSuggest();
        CompletionSuggestion suggestion = suggest.getSuggestion("suggest");

        List<String> suggestions = suggestion
            .getEntries()
            .stream()
            .flatMap(e -> e.getOptions().stream())
            .map(option -> option.getText().string())
            .collect(Collectors.toList());

        return suggestions;
    }
}