前言

你可以通过官网文档看到ElasticSearch7和6的变化，本文的重点在于在SpringBoot环境中使用ElasticSearch7。

软件安装

从官网下载ElasticSearch ，我这里使用的是7.9.3版本 ， 下载Kibana也是7.9.3，以及IK分词器，下载好之后把ElasticSearch进行解压：

把IK分词器解压到plugins/ik目录中，如下：

解压Kibana，目录结构如下

启动ElasticSearch ： elasticsearch-7.9.3\bin\elasticsearch.bat ， 然后启动Kibana ：\kibana-7.9.3-windows-x86_64\bin\kibana.bat ,访问kibana: http://localhost:5601

Spring整合ES7

第一步：导入依赖,SpringBoot使用的是2.4；需要注意版本兼容7.9.3

 <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.4.0</version>
        <relativePath/>
    </parent>

    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-data-elasticsearch</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
        </dependency>
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <version>1.18.12</version>
            <scope>compile</scope>
        </dependency>
        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>fastjson</artifactId>
            <version>1.2.71</version>
        </dependency>
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <scope>test</scope>
        </dependency>
    </dependencies>

第二步：启动类常规写法，yaml配置es地址

server:
  port: 1000
spring:
  elasticsearch:
    rest:
      uris:
        - http://localhost:9200

第三步：编写ES的Doc对象

@Data
//定义索引，7以上的版本去掉了type属性
@Document(indexName = "goodsorder", shards = 1, replicas = 1)
@AllArgsConstructor
@NoArgsConstructor
public class OrderDoc implements Serializable {
    @Id
    @Field(type = FieldType.Keyword)
    private String id;

    @Field(type = FieldType.Long)
    private Long orderNo;
	
    @Field(type = FieldType.Text, analyzer = "ik_smart", searchAnalyzer = "ik_max_word")
    private String title;
	
	//用来封装高亮的结果
    private Map<String, List<String>> highlights;

    public OrderDoc(String id, Long orderNo ,String title){
        this.id = id;
        this.orderNo = orderNo;
        this.title =title;
    }
}

第四步：编写Repository接口

@Repository
//泛型是Doc对象和ID的类型
public interface OrderRepository extends ElasticsearchRepository<OrderDoc, String> {

}

第五步：编写Service接口,定义基本的CRUD方法

public interface OrderDocService {

    void saveAll(List<OrderDoc> orderDocs);

    OrderDoc findById(String id);

    void deleteById(String id);

    void updateById(OrderDoc orderDoc);

    PageResponse<OrderDoc> findList(OrderDoc orderDoc, Integer pageIndex, Integer pageSize);

    PageResponse<OrderDoc> findAll(Integer pageIndex, Integer pageSize);

    PageResponse<OrderDoc> findHighlight(OrderDoc orderDoc, Integer pageIndex, Integer pageSize);
}

下面是实现类，注入OrderRepository和ElasticsearchRestTemplate实现CRUD工作

@Service
public class OrderDocServiceImpl implements OrderDocService {

    @Autowired
    private OrderRepository orderRepository;
    @Autowired
    private ElasticsearchRestTemplate template;

    @Override
    public void saveAll(List<OrderDoc> orderDocs) {
        orderRepository.saveAll(orderDocs);
    }

    @Override
    public OrderDoc findById(String id) {
        return orderRepository.findById(id).orElse(null);
    }

    @Override
    public void deleteById(String id) {
        orderRepository.deleteById(id);
    }

    @Override
    public void updateById(OrderDoc orderDoc) {
        orderRepository.save(orderDoc);
    }

    @Override
    public PageResponse<OrderDoc> findList(OrderDoc orderDoc, Integer pageIndex, Integer pageSize) {
        CriteriaQuery criteriaQuery = new CriteriaQuery(
                new Criteria().and("title").contains(orderDoc.getTitle()),PageRequest.of(pageIndex,pageSize));

        SearchHits<OrderDoc> searchHits = template.search(criteriaQuery, OrderDoc.class);

        List<OrderDoc> orderDocList = searchHits.getSearchHits().stream()
                .map(orderDocSearchHit -> orderDocSearchHit.getContent()).collect(Collectors.toList());

        return new PageResponse<OrderDoc>(searchHits.getTotalHits() ,orderDocList);
    }

    @Override
    public PageResponse<OrderDoc> findAll(Integer pageIndex, Integer pageSize) {
        Page<OrderDoc> page = orderRepository.findAll(PageRequest.of(pageIndex, pageSize));
        return new PageResponse<OrderDoc>(page.getTotalElements(),page.getContent());
    }

    @Override
    public PageResponse<OrderDoc> findHighlight(OrderDoc orderDoc, Integer pageIndex, Integer pageSize) {
        //查询条件
        CriteriaQuery criteriaQuery = new CriteriaQuery(
                new Criteria().and("title").contains(orderDoc.getTitle()),
                PageRequest.of(pageIndex,pageSize));
        //高亮字段
        HighlightBuilder highlightBuilder = new HighlightBuilder();
        highlightBuilder.field("title").preTags("<font style='color:red'>").postTags("</font>");
        criteriaQuery.setHighlightQuery(new HighlightQuery(highlightBuilder));
        //搜索结果
        SearchHits<OrderDoc> searchHits = template.search(criteriaQuery, OrderDoc.class);

        List<OrderDoc> orderDocList = searchHits.get().map(searchHit -> {
            //把高亮结果添加到doc中中
            OrderDoc doc = searchHit.getContent();
            //获取高亮
            doc.setHighlights(searchHit.getHighlightFields());
            return doc;
        }).collect(Collectors.toList());

        //处理结果
        return new PageResponse<>(searchHits.getTotalHits() , orderDocList);
    }
}

下面是需要的结果对象

@Data
@AllArgsConstructor
@NoArgsConstructor
public class PageResponse<T> {
    private Long total;
    private List<T> list;
}

第六步：编写单元测试

@RunWith(SpringRunner.class)
@SpringBootTest(classes = ApplicationStarter.class)
public class OrderDocServiceTest {

    @Autowired
    private OrderDocService orderDocService;

    @Test
    public void saveAll() {
        orderDocService.saveAll(Arrays.asList(
                new OrderDoc("1",100000l,"苹果电脑"),
                new OrderDoc("2",100000l,"苹果电脑"),
                new OrderDoc("3",100000l,"苹果电脑"),
                new OrderDoc("4",100000l,"苹果电脑"),
                new OrderDoc("5",100000l,"苹果电脑"),
                new OrderDoc("6",100000l,"苹果电脑"),
                new OrderDoc("7",100000l,"苹果电脑")
        ));
    }


    @Test
    public void findById() {
        System.out.println(orderDocService.findById("1"));
    }

    @Test
    public void deleteById() {
        orderDocService.deleteById("1");
    }

    @Test
    public void updateById() {
        OrderDoc orderDoc = orderDocService.findById("1");
        orderDoc.setTitle("华为电脑");
        orderDocService.updateById(orderDoc);
    }

    @Test
    public void findList() {
        OrderDoc orderDoc = new OrderDoc(null, 100l, "电脑");
        PageResponse<OrderDoc> response = orderDocService.findList(orderDoc, 0, 10);
        System.out.println(response.getTotal());
        response.getList().forEach(System.out::println);

    }

    @Test
    public void findAll() {
        PageResponse<OrderDoc> response = orderDocService.findAll( 0, 10);
        System.out.println(response.getTotal());
        response.getList().forEach(System.out::println);
    }

    @Test
    public void findHighlight() {
        OrderDoc orderDoc = new OrderDoc(null, 100l, "电脑",null);
        PageResponse<OrderDoc> response = orderDocService.findHighlight( orderDoc,0, 10);
        System.out.println(response.getTotal());
        response.getList().forEach(System.out::println);
    }
}