使用Java REST客户端API的Elasticsearch 6.5.4中的完成建议程序

import org.elasticsearch.action.search.SearchRequest;
import org.elasticsearch.action.search.SearchResponse;
import org.elasticsearch.client.RequestOptions;
import org.elasticsearch.client.RestClient;
import org.elasticsearch.client.RestHighLevelClient;
import org.elasticsearch.index.query.QueryBuilders;
import org.elasticsearch.search.builder.SearchSourceBuilder;
import org.elasticsearch.search.suggest.Suggest;
import org.elasticsearch.search.suggest.SuggestBuilder;
import org.elasticsearch.search.suggest.completion.CompletionSuggestion;

import java.io.IOException;

public class ElasticsearchSuggestionExample {
    public static void main(String[] args) {
        // 创建Elasticsearch客户端
        RestHighLevelClient client = new RestHighLevelClient(
                RestClient.builder("localhost:9200"));

        // 创建建议请求
        SearchRequest request = new SearchRequest("index_name");
        SearchSourceBuilder sourceBuilder = new SearchSourceBuilder();
        SuggestBuilder suggestBuilder = new SuggestBuilder();
        suggestBuilder.addSuggestion("suggestion_name",
                CompletionSuggestionBuilder
                        .prefix("input_text")
                        .field("suggest_field"));
        sourceBuilder.suggest(suggestBuilder);
        request.source(sourceBuilder);

        try {
            // 发送建议请求
            SearchResponse response = client.search(request, RequestOptions.DEFAULT);

            // 处理建议结果
            Suggest suggest = response.getSuggest();
            CompletionSuggestion suggestion = suggest.getSuggestion("suggestion_name");
            for (CompletionSuggestion.Entry entry : suggestion.getEntries()) {
                for (CompletionSuggestion.Entry.Option option : entry) {
                    String text = option.getText().string();
                    double score = option.getScore();
                    // 处理建议结果
                }
            }
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            // 关闭Elasticsearch客户端
            try {
                client.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    }
}