SpringDataElasticsearch 提供了一个工具类 ElasticsearchTemplate，我们使用该类对象也可以对 ES 进行操作
1.操作索引
首先注入操作ES所需要的工具类(ElasticsearchTemplate)。
@Autowiredprivate ElasticsearchTemplate template;将createIndex改为false
@Document(indexName = "product",createIndex = false)
@Data
@AllArgsConstructor
public class Product {@Id //标记在成员变量上，标记一个字段为主键，该字段的值会同步到ES该文档的id值//标记在成员变量上，标记为文档中的域，一般有如下属性-> type域的类型,index是否创建索引,store是否单独存储,analyzer分词器,searchAnalyzer搜索分词器@Field(type = FieldType.Integer,store = true,index = true)private Integer id;@Field(type = FieldType.Text,store = true,index = true,analyzer = "ik_max_word",searchAnalyzer = "ik_max_word")private String productName;@Field(type = FieldType.Text,store = true,index = true,analyzer = "ik_max_word",searchAnalyzer = "ik_max_word")private String productDesc;
}1.1新增索引(不推荐)
不推荐原因：生成的索引中mappings为空，并不按照指定
@Testpublic void addIndex(){//获取索引操作对象IndexOperations indexOperations = template.indexOps(Product.class);//创建索引indexOperations.create();}1.2删除索引
@Testpublic void deleteIndex(){//获取索引操作对象IndexOperations indexOperations = template.indexOps(Product.class);//删除索引indexOperations.delete();}2.操作文档
2.1新增/修改 文档
//新增/修改 文档@Testpublic void addDocument(){Product product = new Product(5, "elasticsearch", "elasticsearch是一款非常好的分词器");template.save(product);}2.2删除文档
@Testpublic void deleteDocument(){template.delete("5",Product.class);}2.3查询文档
//根据id查询
@Testpublic void findDocument(){Product product = template.get("1", Product.class);System.out.println(product);}3.查询文档
template的search方法可以查询文档
SearchHits < T > search ( Query query , Class < T > clazz ) ：查询文档， query 是查询条件对象， clazz 是结果类型。
3.1简单查询
@Testpublic void findDocuments(){//1.构造查询条件NativeQuery query=new NativeQueryBuilder().withQuery(Queries.matchAllQueryAsQuery()).build();//2.查询SearchHits<Product> result = template.search(query, Product.class);//3.处理查询结果for (SearchHit<Product> productSearchHit : result) {System.out.println(productSearchHit.getContent());}}3.2匹配查询
@Testpublic void findDocuments(){//1.构造查询条件NativeQuery query=new NativeQueryBuilder().withQuery(Queries.matchQueryAsQuery("productDesc","手机",null,null)).build();//2.查询SearchHits<Product> result = template.search(query, Product.class);//3.处理查询结果for (SearchHit<Product> productSearchHit : result) {System.out.println(productSearchHit.getContent());}}4.复杂条件查询
@Testpublic void findDocuments2(){String productName="三体";String productDesc="小说";//1.构造查询条件NativeQueryBuilder nativeQueryBuilder = new NativeQueryBuilder();//判断是否有查询条件if (productName== null && productDesc== null){//查询所有nativeQueryBuilder.withQuery(Queries.matchAllQueryAsQuery());}else {//构造bool查询BoolQuery.Builder boolQuery = QueryBuilders.bool();if (productName!=null){//构造must条件boolQuery.must(Queries.matchQueryAsQuery("productName",productName,null,null));}if (productDesc!=null){boolQuery.must(Queries.matchQueryAsQuery("productDesc",productDesc,null,null));}//构造查询条件nativeQueryBuilder.withQuery(boolQuery.build()._toQuery());}//构造查询条件NativeQuery query = nativeQueryBuilder.build();//2.查询SearchHits<Product> result = template.search(query, Product.class);//3.处理查询结果for (SearchHit<Product> productSearchHit : result) {System.out.println(productSearchHit.getContent());}}5.分页查询
@Testpublic void findDocuments3(){//1.构造查询条件//分页条件Pageable pageable = PageRequest.of(0, 3, Sort.by(Sort.Direction.DESC, "id"));NativeQuery query=new NativeQueryBuilder().withQuery(Queries.matchAllQueryAsQuery()).withPageable(pageable).build();//2.查询SearchHits<Product> result = template.search(query, Product.class);//3.处理查询结果ArrayList content = new ArrayList();for (SearchHit<Product> productSearchHit : result) {content.add(productSearchHit.getContent());}/***封装page对象* 参数1：具体数据 参数2：分页条件对象 参数3：总条数*/Page<PageImpl> page = new PageImpl(content, pageable, result.getTotalHits());System.out.println(page.getTotalElements());System.out.println(page.getTotalPages());System.out.println(page.getContent());}6.结果排序
@Testpublic void findDocumentSort(){//1.构造查询条件NativeQuery query=new NativeQueryBuilder().withQuery(Queries.matchAllQueryAsQuery())//Sort.Direction.DESC 降序 Sort.Direction.ASC 升序.withSort(Sort.by(Sort.Direction.DESC,"id")).build();//2.查询SearchHits<Product> result = template.search(query, Product.class);//3.处理查询结果for (SearchHit<Product> productSearchHit : result) {System.out.println(productSearchHit.getContent());}}
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