玩转SpringBoot和Elasticsearch：模糊查询、排序、分页、高亮一网打尽！

2022-12-14 09:46:11

Springboot与Elasticsearch完美融合：玩转搜索新体验

拥抱Elasticsearch，开启强大搜索新篇章

在现代网络应用中，搜索功能扮演着至关重要的角色。无论是电子商务网站还是内容丰富的博客，强大的搜索功能都是用户体验的基石。而说到搜索，Elasticsearch无疑是您的不二之选。它不仅拥有无与伦比的搜索能力，还支持多种多样的查询类型，如模糊查询、排序、分页、高亮等等。

一步步指南：将Elasticsearch注入您的项目

1. 构建SpringBoot项目：

创建一个新的SpringBoot项目，或选择一个现有的项目作为起点。

2. 引入Elasticsearch依赖：

在项目的pom.xml文件中添加Elasticsearch依赖：

<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-data-elasticsearch</artifactId>
    <version>2.6.7</version>
</dependency>

3. 创建Elasticsearch客户端：

使用Elasticsearch官方客户端或第三方客户端创建客户端对象：

ElasticsearchClient client = new RestHighLevelClient(
        RestClient.builder(new HttpHost("localhost", 9200))
);

4. 配置Elasticsearch索引和类型：

定义要使用的Elasticsearch索引和类型，并设置必要的映射：

CreateIndexRequest request = new CreateIndexRequest("my_index");
request.settings(Settings.builder()
        .put("index.number_of_shards", 5)
        .put("index.number_of_replicas", 1)
);
client.indices().create(request, RequestOptions.DEFAULT);

5. 操作Elasticsearch数据：

使用客户端对象对数据进行索引、更新、删除等操作：

IndexRequest indexRequest = new IndexRequest("my_index", "my_type", "1");
indexRequest.source(jsonBuilder()
        .startObject()
        .field("title", "Elasticsearch Tutorial")
        .field("content", "This is an Elasticsearch tutorial.")
        .endObject());
client.index(indexRequest, RequestOptions.DEFAULT);

6. 进行搜索查询：

使用Elasticsearch提供的查询DSL进行模糊查询、排序、分页、高亮等查询操作：

SearchRequest searchRequest = new SearchRequest("my_index");
searchRequest.source(jsonBuilder()
        .startObject()
        .query(
                QueryBuilders.matchQuery("content", "Elasticsearch")
                        .fuzziness(Fuzziness.TWO)
        )
        .endObject());
SearchResponse response = client.search(searchRequest, RequestOptions.DEFAULT);

// 打印查询结果
for (SearchHit hit : response.getHits().getHits()) {
    System.out.println(hit.getSourceAsMap());
}

代码示例：让Elasticsearch操作轻松自如

// 创建Elasticsearch客户端对象
ElasticsearchClient client = new RestHighLevelClient(
        RestClient.builder(new HttpHost("localhost", 9200))
);

// 创建索引和类型
CreateIndexRequest request = new CreateIndexRequest("my_index");
request.settings(Settings.builder()
        .put("index.number_of_shards", 5)
        .put("index.number_of_replicas", 1)
);
client.indices().create(request, RequestOptions.DEFAULT);

// 索引文档
IndexRequest indexRequest = new IndexRequest("my_index", "my_type", "1");
indexRequest.source(jsonBuilder()
        .startObject()
        .field("title", "Elasticsearch Tutorial")
        .field("content", "This is an Elasticsearch tutorial.")
        .endObject());
client.index(indexRequest, RequestOptions.DEFAULT);

// 进行模糊查询
SearchRequest searchRequest = new SearchRequest("my_index");
searchRequest.source(jsonBuilder()
        .startObject()
        .query(
                QueryBuilders.matchQuery("content", "Elasticsearch")
                        .fuzziness(Fuzziness.TWO)
        )
        .endObject());
SearchResponse response = client.search(searchRequest, RequestOptions.DEFAULT);

// 打印查询结果
for (SearchHit hit : response.getHits().getHits()) {
        System.out.println(hit.getSourceAsMap());
}

// 进行排序查询
searchRequest = new SearchRequest("my_index");
searchRequest.source(jsonBuilder()
        .startObject()
        .query(QueryBuilders.matchAllQuery())
        .sort(
                SortBuilders.fieldSort("title")
                        .order(SortOrder.ASC)
        )
        .endObject());
response = client.search(searchRequest, RequestOptions.DEFAULT);

// 打印查询结果
for (SearchHit hit : response.getHits().getHits()) {
        System.out.println(hit.getSourceAsMap());
}

// 进行分页查询
searchRequest = new SearchRequest("my_index");
searchRequest.source(jsonBuilder()
        .startObject()
        .query(QueryBuilders.matchAllQuery())
        .from(0)
        .size(10)
        .endObject());
response = client.search(searchRequest, RequestOptions.DEFAULT);

// 打印查询结果
for (SearchHit hit : response.getHits().getHits()) {
        System.out.println(hit.getSourceAsMap());
}

// 进行高亮查询
searchRequest = new SearchRequest("my_index");
searchRequest.source(jsonBuilder()
        .startObject()
        .query(QueryBuilders.matchQuery("title", "Elasticsearch"))
        .highlight(
                HighlightBuilder.highlightFields()
                        .field("title")
                        .preTags("<b>")
                        .postTags("</b>")
        )
        .endObject());
response = client.search(searchRequest, RequestOptions.DEFAULT);

// 打印查询结果
for (SearchHit hit : response.getHits().getHits()) {
        System.out.println(hit.getHighlightFields());
}