本文介紹spring-data-elasticsearch:jar:4.0.0.RELEASE版本completion suggest的使用狈茉。
主要用到CompletionSuggestionBuilder,SuggestBuilder這兩個(gè)類
同QueryBuilders一樣suggest也有一個(gè)SuggestBuilders用于構(gòu)建term,phrase,completion三種類型的suggest構(gòu)造器

CompletionSuggestionBuilder textBuilder = 
SuggestBuilders.completionSuggestion("goodsName.suggest")

而對(duì)于Completion的Context Suggest，我們就要用到CategoryQueryContext和GeoQueryContext
如下：

CategoryQueryContext categoryQueryContext = 
CategoryQueryContext.builder().setCategory(cityCode).build();

注意，這里的cityCode是從前端傳遞過(guò)來(lái)的一個(gè)動(dòng)態(tài)參數(shù)原朝，用于限定城市。
接下來(lái)將其封裝到Map中

Map<String, List<? extends ToXContent>> contexts = new HashMap<>();
List<CategoryQueryContext> list = new ArrayList<>();
list.add(categoryQueryContext);
contexts.put("city", list); // 這里要和mapping中配置的name保持一致

最后我們把拼裝好的contexts放到CompletionSuggestionBuilder中

textBuilder.contexts(contexts);

完整代碼如下：

public List<String> suggest(String keyword, String cityCode) {
        HashSet<String> returnSet = new LinkedHashSet<>(); // 用于存儲(chǔ)查詢到的結(jié)果
        // 創(chuàng)建CompletionSuggestionBuilder
        CompletionSuggestionBuilder textBuilder = SuggestBuilders.completionSuggestion("goodsName.suggest") // 指定字段名
        .size(10) // 設(shè)定返回?cái)?shù)量
        .skipDuplicates(true) // 去重
        // 配置context
        CategoryQueryContext categoryQueryContext = CategoryQueryContext.builder().setCategory(cityCode).build();
        Map<String, List<? extends ToXContent>> contexts = new HashMap<>();
        List<CategoryQueryContext> list = new ArrayList<>();
        list.add(categoryQueryContext);
        contexts.put("city", list);
        textBuilder.contexts(contexts); // 設(shè)置contexts
        // 創(chuàng)建suggestBuilder并將completionBuilder添加進(jìn)去
        SuggestBuilder suggestBuilder = new SuggestBuilder();
        suggestBuilder.addSuggestion("suggest_text", textBuilder)
        .setGlobalText(keyword); 
        // 執(zhí)行請(qǐng)求
        Suggest suggest = elasticsearchRestTemplate.suggest(suggestBuilder, elasticsearchRestTemplate.getIndexCoordinatesFor(Goods.class)).getSuggest();
        // 取出結(jié)果
        Suggest.Suggestion<Entry<Option>> textSuggestion = suggest.getSuggestion("suggest_text");
        for (Entry<Option> entry : textSuggestion.getEntries()) {
            List<Option> options = entry.getOptions();
            for (Suggest.Suggestion.Entry.Option option : options) {
                returnSet.add(option.getText().toString());
            }
        }
        return new ArrayList<>(returnSet);
    }

引入的相關(guān)類

import org.elasticsearch.search.suggest.Suggest;
import org.elasticsearch.search.suggest.Suggest.Suggestion.Entry;
import org.elasticsearch.search.suggest.Suggest.Suggestion.Entry.Option;
import org.elasticsearch.search.suggest.SuggestBuilder;
import org.elasticsearch.search.suggest.SuggestBuilders;
import org.elasticsearch.search.suggest.completion.CompletionSuggestionBuilder;
import org.elasticsearch.search.suggest.completion.context.CategoryQueryContext;

Goods.java

@Document(indexName = "goods", shards = 1, replicas = 0)
@Mapping(mappingPath = "/mappings/goods.json")
@Data
public class Goods {
    @Id
    private Long goodsId;
    private String goodsName;
    private String cityCode;
}

由于此版本中FieldType并沒(méi)有提供Completion類型，使用@MultiField無(wú)法達(dá)到目的，因此用@Mapping方式進(jìn)行配置
goods.json

{
  "properties": {
    "goodsName": {
      "type": "text",
      "analyzer": "ik_max_word", 
      "search_analyzer": "ik_smart",
      "fields": {
        "suggest": {
          "type": "completion",
          "analyzer": "standard",
          "contexts": [
            {                           
              "name": "city",
              "type": "category",
              "path": "cityCode"
            }
          ]
        }
      }
    }
  }
}

本文重點(diǎn)介紹4.x版本Completion Suggest的使用蒜焊，如何做到更精確的查找，網(wǎng)上有很多科贬，就不在這里介紹了泳梆。
如果您覺(jué)得有幫助，還望留下一個(gè)贊唄榜掌。