使用Java API的ElasticSearch完成建议器

我在网上尝试了一些关于ElasticSearch的suggester特性的示例代码，但我无法解决自动完成解决方案的问题

我的索引：

client.prepareIndex("kodcucom", "article", "1")
      .setSource(putJsonDocument("ElasticSearch: Java",
        "ElasticSeach provides Java API, thus it executes all operations " +
        "asynchronously by using client object..",
         new Date(),
         new String[]{"elasticsearch"},
         "Hüseyin Akdoğan")).execute().actionGet();

我使用suggestbuilder获取关键字，然后扫描内容“字段”，这里是由于没有结果而出现空指针异常的地方

CompletionSuggestionBuilder skillNameSuggest = new CompletionSuggestionBuilder("skillNameSuggest");

skillNameSuggest.text("lien");
skillNameSuggest.field("content");

SuggestRequestBuilder suggestRequestBuilder = client.prepareSuggest("kodcucom").addSuggestion(skillNameSuggest);

SuggestResponse suggestResponse = suggestRequestBuilder.execute().actionGet();

Iterator<? extends Suggest.Suggestion.Entry.Option> iterator =
          suggestResponse.getSuggest().getSuggestion("skillNameSuggest").iterator().next().getOptions().iterator();

编辑2: 我使用的是ElasticSearchJavaAPI的2.1.1版本

编辑3: 我尝试将迭代器行拆分为几个代码块，当将一组数据转换为迭代器时，NPE出现在最后一行，但没有太多帮助

Suggest tempSuggest = suggestResponse.getSuggest();

Suggestion tempSuggestion = tempSuggest.getSuggestion("skillNameSuggest");

Iterator tempIterator = tempSuggestion.iterator();

我看到代码：

SuggestRequestBuilder suggestRequestBuilder = client.prepareSuggest("kodcucom").addSuggestion(skillNameSuggest);

    SuggestResponse suggestResponse = suggestRequestBuilder.execute().actionGet();

---

已包含一个空数组/数据集，我是否错误地使用了“建议请求生成器”？

为了使用完成功能，您需要专门指定一个字段，称为完成，并且必须为其指定一个特殊映射

例如：

"mappings": {
   "article": {
     "properties": {
      "content": {
        "type": "string"
      },
     "completion_suggest": {
      "type": "completion"}
     }
   }
}

completion\u suggest字段是我们将在上述代码示例中用于autocomplete函数的字段。在此映射定义之后，数据必须按如下方式进行索引：

curl -XPOST localhost:9200/kodcucom/article/1 -d '{
   "content": "elasticsearch",
   "completion_suggest": {
     "input": [ "es", "elastic", "elasticsearch" ],
     "output": "ElasticSearch"
   }
}'

然后Java API可以按如下方式用于获取建议：

CompletionSuggestionBuilder skillNameSuggest  = new CompletionSuggestionBuilder("complete");
skillNameSuggest.text("es");
skillNameSuggest.field("completion_suggest");

SearchResponse searchResponse = client.prepareSearch("kodcucom")
        .setTypes("article")
        .setQuery(QueryBuilders.matchAllQuery())
        .addSuggestion(skillNameSuggest)
        .execute().actionGet();

CompletionSuggestion compSuggestion = searchResponse.getSuggest().getSuggestion("complete");

List<CompletionSuggestion.Entry> entryList = compSuggestion.getEntries();
if(entryList != null) {
    CompletionSuggestion.Entry entry = entryList.get(0);
    List<CompletionSuggestion.Entry.Option> options =entry.getOptions();
    if(options != null)  {
        CompletionSuggestion.Entry.Option option = options.get(0);
        System.out.println(option.getText().string());
    }
}

CompletionSuggestionBuilder skillNameSuggest=新的CompletionSuggestionBuilder（“完成”）；
技能名称建议文本（“es”）；
技能名称建议字段（“完成建议”）；
SearchResponse SearchResponse=client.prepareSearch（“kodcucom”）
.setTypes（“条款”）
.setQuery（QueryBuilders.matchAllQuery（））
.addSuggest（skillNameSuggest）
.execute（）.actionGet（）；
CompletionSuggestion compSuggestion=searchResponse.getSuggestion（）.getSuggestion（“完成”）；
List entryList=compSuggestion.getEntries（）；
if（entryList！=null）{
CompletionSuggestion.Entry=entryList.get（0）；
List options=entry.getOptions（）；
如果（选项！=null）{
CompletionSuggestion.Entry.Option=options.get（0）；
System.out.println（option.getText（）.string（））；
}
}

以下链接提供了有关如何创建建议索引的详细信息

现在，我使用异步SuggestionBuilderJavaAPI根据术语生成建议

 SearchRequestBuilder suggestionsExtractor = elasticsearchService.suggestionsExtractor("yourIndexName", "yourIndexType//not necessary", "name_suggest", term);
        System.out.println(suggestionsExtractor);
        Map<String,Object> suggestionMap = new HashMap<>();
        suggestionsExtractor.execute(new ActionListener<SearchResponse>() {
            @Override
            public void onResponse(SearchResponse searchResponse) {
               if(searchResponse.status().equals(RestStatus.OK)) {
                   searchResponse.getSuggest().getSuggestion("productsearch").getEntries().forEach(e -> {
                       e.getOptions().forEach(s -> {
                           ArrayList<Object> contents = new ArrayList<>();

                           suggestionMap.put(s.getText().string(), s.getScore());

                       });
                   });


               }

            }

            @Override
            public void onFailure(Exception e) {
                Helper.sendErrorResponse(routingContext,new JsonObject().put("details","internal server error"));
                e.printStackTrace();
            }
        });

---

您从哪里获得NPE（即stacktrace）？请原谅我是ES中的新手，什么是NPE和stacktrace？对不起，NPE是空指针异常的缩写，即运行Java程序时控制台中出现的错误（=stacktrace）。我更新了我的问题，谢谢，您的第一个代码块的

suggestResponse

为空，如何在java语法中实现这一点？

CreateIndexRequestBuilder CreateIndexRequestBuilder=client.admin（）.index（）.prepareCreate（“您的索引名称”）；XContentBuilder mappingBuilder=jsonBuilder（）.startObject（）.startObject（“您的类型\名称”）.startObject（“属性”）.startObject（“您的完成\字段”）.field（“类型”，“完成”）.endObject（）.endObject（）.endObject（）.endObject（）.endObject（）.endObject（）.endObject（）；addMapping（“yoru_索引_名称”，mappingBuilder）；createIndexRequestBuilder.execute（）.actionGet（）谢谢：）说得对
 SearchRequestBuilder suggestionsExtractor = elasticsearchService.suggestionsExtractor("yourIndexName", "yourIndexType//not necessary", "name_suggest", term);
        System.out.println(suggestionsExtractor);
        Map<String,Object> suggestionMap = new HashMap<>();
        suggestionsExtractor.execute(new ActionListener<SearchResponse>() {
            @Override
            public void onResponse(SearchResponse searchResponse) {
               if(searchResponse.status().equals(RestStatus.OK)) {
                   searchResponse.getSuggest().getSuggestion("productsearch").getEntries().forEach(e -> {
                       e.getOptions().forEach(s -> {
                           ArrayList<Object> contents = new ArrayList<>();

                           suggestionMap.put(s.getText().string(), s.getScore());

                       });
                   });


               }

            }

            @Override
            public void onFailure(Exception e) {
                Helper.sendErrorResponse(routingContext,new JsonObject().put("details","internal server error"));
                e.printStackTrace();
            }
        });

public SearchRequestBuilder suggestionsExtractor(String indexName, String typeName, String field, String term) {

        CompletionSuggestionBuilder csb = SuggestBuilders.completionSuggestion(field).text(term);
        SearchRequestBuilder suggestBuilder = client.prepareSearch()
                .suggest(new SuggestBuilder().addSuggestion(indexName, csb));
        return suggestBuilder;
    }