😊SpringBoot 整合 Elasticsearch (超详细).md

SpringBoot 整合 Elasticsearch (超详细)

注意:

1、环境搭建

安装es

🔗Elasticsearch 6.4.3 下载链接

为了方便,环境使用Windows

配置

🍑解压后配置

  • 找到config目录的elasticsearch.yml
  • image-20221109152237692

分词器

下图所示,解压后的分词器放在plugins目录下,ik目录需要自己创建

image-20221109154446235

启动

  • 🍈 由于我是在Windows环境下,找到bin目录的elasticsearch.bat双击即可。

命令测试

  • 🚆 查看健康状态
    • curl -X GET “localhost:9200/_cat/health?v“
  • 🚖 查看所有节点
    • curl -X GET “localhost:9200/_cat/nodes?v“
  • 🏅 新建索引
    • curl -X PUT “localhost:9200/test”
  • ☀️ 查看索引
    • curl -X GET “localhost:9200/_cat/indices?v”
  • 🌈 删除索引
    • curl -X DELETE “localhost:9200/test”

2、整合 Es

依赖 & 配置

  • ❌ 我这里使用的是SpringBoot 2.1.5.RELEASE,根据实际情况选择版本。
		<!--elasticsearch-->
        <dependency>
            <groupId>org.springframework.data</groupId>
            <artifactId>spring-data-elasticsearch</artifactId>
            <version>2.1.6.RELEASE</version>
        </dependency>
  • yaml配置

image-20221109233533596

  • properties配置
spring.data.elasticsearch.cluster-name=community
spring.data.elasticsearch.cluster-nodes=127.0.0.1:9300

启动项目:

  • ❌ 不出意外肯定会出意外

image-20221109234157966

  • ❓ 这个问题是由于Es底层的问题,这里就不展开解释,会提供思路,自行了解

解决办法:

image-20221109234326083

3、使用

SpringBoot 整合 Elasticsearch视频教程

实体类

  • ❌ 相信之前学过Jpa的同学,对于以下配置很熟悉。
import lombok.Data;
import org.springframework.data.annotation.Id;
import org.springframework.data.elasticsearch.annotations.Document;
import org.springframework.data.elasticsearch.annotations.Field;
import org.springframework.data.elasticsearch.annotations.FieldType;
// 指定Es 索引 类型 分片 备份
@Document(indexName = "discusspost", type = "_doc", shards = 6, replicas = 3)
@Data
public class DiscussPost implements Serializable {
    private static final long serialVersionUID = 114809849189593294L;

    // 标识主键
    @Id
    private Integer id;
	
    // 对应文档类型
    @Field(type = FieldType.Integer)
    private Integer userId;

    /**
     * type 类型
     * analyzer 存储解析器
     * searchAnalyzer 查询解析器
     */
    @Field(type = FieldType.Text, analyzer = "ik_max_word", searchAnalyzer = "ik_smart")
    private String title;
    @Field(type = FieldType.Text, analyzer = "ik_max_word", searchAnalyzer = "ik_smart")
    private String content;
}

持久层

  • ElasticsearchRepository 里面有许多常用方法
@Repository
public interface DiscussPostRepository extends ElasticsearchRepository<DiscussPost, Integer> {
}

测试代码

  • ❌ 查询数据层的代码就不展示了,我会在代码中说明
  • 😊 时间足够,建议把视频看完
/**
 * @author : look-word
 * 2022-11-03 18:56
 **/
@SpringBootTest
@RunWith(SpringRunner.class)
public class ElasticSearchTest {

    @Resource
    private DiscussPostRepository discussPostRepository;

    @Resource
    private DiscussPostMapper discussPostMapper;

    @Resource
    private ElasticsearchTemplate elasticsearchTemplate;

    @Test
    public void testInsert() {
        // 将查询的结果,同步到Es中
        discussPostRepository.save(discussPostMapper.selectDiscussPostById(241));
    }

    @Test
    public void testInsertAll() {
        // 批量导入 discussPostRepository.saveAll()
        discussPostRepository.saveAll(discussPostMapper.selectDiscussPosts(101, 0, 100));
    }

    /**
     * 测试更新
     */
    @Test
    public void testUpdate() {
        DiscussPost discussPost = discussPostMapper.selectDiscussPostById(241);
        discussPost.setContent("我爱中华人民共和国,我是中国人");
        discussPostRepository.save(discussPost);
    }

    /**
     * 测试修改
     */
    @Test
    public void testDelete() {
        discussPostRepository.deleteById(241);
    }

    /**
     * 测试查询
     */
    @Test
    public void testSelect() {
        // 构造查询条件
        SearchQuery searchQuery = new NativeSearchQueryBuilder()
            	// (查询的值,查询字段1,查询字段1) 匹配title或者title里面是否含有互联网寒冬
                .withQuery(QueryBuilders.multiMatchQuery("互联网寒冬", "title", "title"))
                .withSort(SortBuilders.fieldSort("type").order(SortOrder.DESC)) // 排序
                .withSort(SortBuilders.fieldSort("score").order(SortOrder.DESC))
                .withSort(SortBuilders.fieldSort("createTime").order(SortOrder.DESC))
                .withPageable(PageRequest.of(0, 10)) // 分页
                .withHighlightFields(
                        new HighlightBuilder.Field("title").preTags("<em>").postTags("</em>"),
                        new HighlightBuilder.Field("content").preTags("<em>").postTags("</em>")
                ).build(); //高亮
        Page<DiscussPost> page = discussPostRepository.search(searchQuery);
        page.get().forEach(System.out::println);
    }

    /**
     * 测试查询高亮显示
     */
    @Test
    public void testSelectHighlight() {
        // 构造查询条件
        SearchQuery searchQuery = new NativeSearchQueryBuilder()
                .withQuery(QueryBuilders.multiMatchQuery("互联网寒冬", "title", "content"))
                .withSort(SortBuilders.fieldSort("type").order(SortOrder.DESC)) // 排序
                .withSort(SortBuilders.fieldSort("score").order(SortOrder.DESC))
                .withSort(SortBuilders.fieldSort("createTime").order(SortOrder.DESC))
                .withPageable(PageRequest.of(0, 10)) // 分页
                .withHighlightFields(
                        new HighlightBuilder.Field("title").preTags("<em>").postTags("</em>"),
                        new HighlightBuilder.Field("content").preTags("<em>").postTags("</em>")
                ).build(); //高亮

        Page<DiscussPost> page = elasticsearchTemplate.queryForPage(searchQuery, DiscussPost.class, new SearchResultMapper() {
            @Override
            public <T> AggregatedPage<T> mapResults(SearchResponse response, Class<T> aClass, Pageable pageable) {
                SearchHits hits = response.getHits();
                if (hits.getTotalHits() <= 0) {
                    return null;
                }
                List<DiscussPost> list = new ArrayList<>();
                for (SearchHit hit : hits) {
                    DiscussPost post = new DiscussPost();

                    String id = hit.getSourceAsMap().get("id").toString();
                    post.setId(Integer.parseInt(id));

                    String userId = hit.getSourceAsMap().get("userId").toString();
                    post.setUserId(Integer.parseInt(userId));

                    String title = hit.getSourceAsMap().get("title").toString();
                    post.setTitle(title);

                    String content = hit.getSourceAsMap().get("content").toString();
                    post.setContent(content);

                    String type = hit.getSourceAsMap().get("type").toString();
                    post.setType(Integer.parseInt(type));

                    String status = hit.getSourceAsMap().get("status").toString();
                    post.setStatus(Integer.parseInt(status));

                    String createTime = hit.getSourceAsMap().get("createTime").toString();
                    post.setCreateTime(new Date(Long.parseLong(createTime)));

                    String commentCount = hit.getSourceAsMap().get("commentCount").toString();
                    post.setCommentCount(Integer.parseInt(commentCount));

                    String score = hit.getSourceAsMap().get("score").toString();
                    post.setScore(Double.parseDouble(score));

                    // 处理高亮
                    HighlightField titleField = hit.getHighlightFields().get("title");
                    // 页面有多个高亮字 只显示第一个
                    if (titleField != null) {
                        post.setTitle(titleField.getFragments()[0].toString());
                    }
                    HighlightField contentField = hit.getHighlightFields().get("content");
                    if (contentField != null) {
                        post.setTitle(contentField.getFragments()[0].toString());
                    }
                    list.add(post);
                }
                return new AggregatedPageImpl(list, pageable, hits.getTotalHits(), response.getAggregations(), response.getScrollId(), hits.getMaxScore());
            }
        });
        page.get().forEach(System.out::println);
    }
}