前言
ElasticsearchRestTemplate是spring-data-elasticsearch项目中的一个类,和其他spring项目中的template类似。
网上的学习资料大都是基于ElasticsearchTemplate,但是ElasticsearchTemplate在未来的版本会被废除
预备知识
- 建立索引
因为是基于springboot,那就不再使用kibana进行建立索引,而是用springboot来创建.创建索引的api:
ElasticsearchRestTemplate.createIndex(实体类.class)
如,现在创建一个名为esBean的实体类
相当于建库:
@Document用于指定索引
@Field(type = FieldType.Text,analyzer = “ik_max_word”)用于指定类型
@Data
@NoArgsConstructor
@Document(indexName = "test")
public class esBean {@Idprivate int id;@Field(type = FieldType.Text,analyzer = "ik_max_word")private String name;@Field(type = FieldType.Text,analyzer = "ik_max_word")private String tags;public esBean(int id,String name,String tags){this.id=id;this.name=name;this.tags=tags;}
}
service层:
public class esService implements IesService {@Autowiredprivate ElasticsearchRestTemplate template;@Overridepublic void create(){template.createIndex(esBean.class);}
}
像这样,就会自动建立一个名为test的索引,表结果就是esBean的成员
存储数据
需要一个持久化层的接口去继承ElasticsearchRepository,接着在service层中,依赖注入,直接调用其saveAll()方法即可,如下:
持久层:(可以在这里做一些搜索查询)
@Service
public interface esMapper extends ElasticsearchRepository<esBean,Long> {}
service层:
可以看到,saveAll,findAll这些方法是原来就有的,无需自己定义
public class esService implements IesService {@Autowiredprivate ElasticsearchRestTemplate template;@AutowiredesMapper mapper;@Overridepublic Iterator<esBean> findAll() {return mapper.findAll().iterator();}public void create(){template.createIndex(esBean.class);}@Overridepublic void saveAll(List<esBean> list) {mapper.saveAll(list);}
}
controller层:
@AutowiredIesService iesService;@GetMapping("/init1")public String init1(){iesService.create();// id name tagsList<esBean>list=new ArrayList<>();list.add(new esBean(1,"张三锕爱","很帅,有很多人喜欢他"));list.add(new esBean(2,"李四酷狗","很帅,但是讨厌他"));list.add(new esBean(3,"王五王二爷","很丑,有是喜欢他"));list.add(new esBean(4,"张三王二婆","很帅,有没人喜欢他"));iesService.saveAll(list);return "success";}
ElasticsearchRestTemplate的基本api
SearchQuery 总的查询
BoolQueryBuilder bool查询,可在后面加上must,mustNot,should等等
MatchQueryBuilder 匹配查询
TermQueryBuilder 倒排索引查询
HighlightBuilder 高亮查询,用于设置要高亮的field
SearchHit 查询结果
实现文本高亮检索步骤
实体类:
@Data
@NoArgsConstructor
@Document(indexName = "test5")
public class esBean {@Idprivate int id;@Field(type = FieldType.Text,analyzer = "ik_max_word")private String name;@Field(type = FieldType.Text,analyzer = "ik_max_word")private String tags;public esBean(int id,String name,String tags){this.id=id;this.name=name;this.tags=tags;}
}
持久层
@Service
public interface esMapper extends ElasticsearchRepository<esBean,Long> {}
service:
public interface IesService {public Iterator<esBean> findAll();public void saveAll(List<esBean> list);public void create();public AggregatedPage testForHigh() throws IOException;
}
@Service
public class esService implements IesService {@Autowiredprivate ElasticsearchRestTemplate template;@AutowiredesMapper mapper;@Overridepublic Iterator<esBean> findAll() {return mapper.findAll().iterator();}public void create(){template.createIndex(esBean.class);}@Overridepublic void saveAll(List<esBean> list) {mapper.saveAll(list);}public AggregatedPage testForHigh() throws IOException {String preTag = "<font color='#dd4b39'>";//google的色值String postTag = "</font>";BoolQueryBuilder boolQueryBuilder=new BoolQueryBuilder().must(new MatchQueryBuilder("tags","很帅"));SearchQuery searchQuery=new NativeSearchQueryBuilder(). //总的查询withQuery(boolQueryBuilder). //设置bool查询withHighlightFields(new HighlightBuilder.Field("name").preTags(preTag).postTags(postTag)).//设置高亮效果withHighlightFields(new HighlightBuilder.Field("tags").preTags(preTag).postTags(postTag)).build();AggregatedPage<esBean> ideas=template.queryForPage(searchQuery, esBean.class, new SearchResultMapper() {@Overridepublic <T> AggregatedPage<T> mapResults(SearchResponse searchResponse, Class<T> aClass, Pageable pageable) {List<esBean> list = new ArrayList<>();for(SearchHit hit:searchResponse.getHits()){//获取遍历查询结果if(searchResponse.getHits().getHits().length<=0)return null;esBean bean=new esBean();Map map=hit.getSourceAsMap();System.out.println(map);bean.setId((Integer)map.get("id"));bean.setName((String)map.get("name"));HighlightField name=hit.getHighlightFields().get("name");if(name!=null){bean.setName(name.fragments()[0].toString()); //得到高亮的结果}HighlightField tags=hit.getHighlightFields().get("tags");if(tags!=null){bean.setTags(tags.fragments()[0].toString());}list.add(bean);}if(list.size()>0)return new AggregatedPageImpl<>((List<T>)list);return null;}@Overridepublic <T> T mapSearchHit(SearchHit searchHit, Class<T> aClass) {return null;}});ideas.get().forEach(model->{System.out.println(model);});return ideas;}@Overridepublic <T> T mapSearchHit(SearchHit searchHit, Class<T> aClass) {return null;}});ideas.get().forEach(model->{System.out.println(model);});return ideas;}
}
controller:
@RestController
@RequestMapping("/elastic")
public class ElasticController {@AutowiredIesService iesService;@GetMapping("/init1")public String init1(){iesService.create();// id name tagsList<esBean>list=new ArrayList<>();list.add(new esBean(1,"张三锕爱","很帅,有很多人喜欢他"));list.add(new esBean(2,"李四酷狗","很帅,但是讨厌他"));list.add(new esBean(3,"王五王二爷","很丑,有是喜欢他"));list.add(new esBean(4,"张三王二婆","很帅,有没人喜欢他"));iesService.saveAll(list);return "success";}@GetMapping("/get1")public AggregatedPage get1() throws IOException {return iesService.testForHigh();}}
postman访问: