ES-java

全文搜索，拆分，分词--获得id，获取部分数据装载进去，简化版数据，用一种状态展示出来，点击详情走的是数据库查询查看显示详情

倒排索引（特征），创建文档，使用文档--加速查询

下载Elasticsearch 7.16.2 | Elastic

打开，目录E:\soft\elasticsearch-7.16.2\bin中的elasticsearch.bat文件，双击即可，首次打开较慢，时间还行，里面两个端口，9300与9200，9200是对外访问端口，启动成功，直接浏览器访问http://localhost:9200/即可

IK分词器Releases · medcl/elasticsearch-analysis-ik · GitHub

下载好的ik分词器东西放置在这里E:\soft\elasticsearch-7.16.2\plugins\ik，重启

http://localhost:9200/books   Body   raw   JSON

{

    "mappings":{

        "properties":{

            "id":{

                "type":"keyword"//关键字

            },

            "name":{

                "type":"text",//文本

                "analyzer":"ik_max_word"，//分词器

                "copy_to":"all"//拷贝到虚拟字段all中

            },

             "type":{

                "type":"keyword"//关键字

            },

            "description":{

                "type":"text",//文本

                "analyzer":"ik_max_word",//分词器

                "copy_to":"all"//拷贝到虚拟字段all中

            },

            "all":{

                "type":"text",

                "analyzer":"ik_max_word"

            }

        }

    }

}

主要的几个方法

private RestHighLevelClient client;

//创建索引
@Test
void testCreateIndexByIk() throws IOException {
    //客户端操作
    CreateIndexRequest request = new CreateIndexRequest("books");
    //设置请求中的参数
    String json = "{\n" +
            "    \"mappings\":{\n" +
            "        \"properties\":{\n" +
            "            \"id\":{\n" +
            "                \"type\":\"keyword\"\n" +
            "            },\n" +
            "            \"name\":{\n" +
            "                \"type\":\"text\",\n" +
            "                \"analyzer\":\"ik_max_word\",\n" +
            "                \"copy_to\":\"all\"\n" +
            "            },\n" +
            "             \"type\":{\n" +
            "                \"type\":\"keyword\"\n" +
            "            },\n" +
            "            \"description\":{\n" +
            "                \"type\":\"text\",\n" +
            "                \"analyzer\":\"ik_max_word\",\n" +
            "                \"copy_to\":\"all\"\n" +
            "            },\n" +
            "            \"all\":{\n" +
            "                \"type\":\"text\",\n" +
            "                \"analyzer\":\"ik_max_word\"\n" +
            "            }\n" +
            "        }\n" +
            "    }\n" +
            "}";
    request.source(json, XContentType.JSON);
    //获取操作索引的客户端对象，调用创建索引操作
    client.indices().create(request, RequestOptions.DEFAULT);
}

//添加全部文档
@Test
void testCreateDocAll() throws IOException {
    List bookList = bookMapper.selectList(null);
    BulkRequest bulk = new BulkRequest();
    for (Book book : bookList) {
        IndexRequest request = new IndexRequest("books").id(book.getId().toString());
        //对象转json
        String json = JSON.toJSONString(book);
        request.source(json,XContentType.JSON);
        bulk.add(request);
    }
    client.bulk(bulk,RequestOptions.DEFAULT);
}

//按id查询文档
@Test
void testGrtById() throws IOException {
    GetRequest request = new GetRequest("books","1");
    GetResponse documentFields = client.get(request, RequestOptions.DEFAULT);
    String sourceAsString = documentFields.getSourceAsString();
    System.out.println(sourceAsString);
}

//按条件查询文档
@Test
void testSearch() throws IOException {
    //创建查books的索引
    SearchRequest searchRequest = new SearchRequest("books");
    //设置查询条件
    SearchSourceBuilder builder = new SearchSourceBuilder();
    builder.query(QueryBuilders.termQuery("all","java"));
    searchRequest.source(builder);

    SearchResponse search = client.search(searchRequest, RequestOptions.DEFAULT);
    SearchHits hits = search.getHits();//命中的数据
    for (SearchHit hit : hits) {
        String sourceAsString = hit.getSourceAsString();
        //System.out.println(sourceAsString);
        //json转对象
        Book book = JSON.parseObject(sourceAsString, Book.class);
        System.out.println(book);
    }
}