• Elasticsearch编程操作


    1.创建工程导入依赖

    <dependency>
          <groupId>org.elasticsearch</groupId>
          <artifactId>elasticsearch</artifactId>
          <version>5.6.8</version>
        </dependency>
        <dependency>
          <groupId>org.elasticsearch.client</groupId>
          <artifactId>transport</artifactId>
          <version>5.6.8</version>
        </dependency>
        <!-- https://mvnrepository.com/artifact/org.apache.logging.log4j/log4j-to-slf4j -->
        <dependency>
          <groupId>org.apache.logging.log4j</groupId>
          <artifactId>log4j-to-slf4j</artifactId>
          <version>2.13.0</version>
        </dependency>
        <dependency>
          <groupId>org.slf4j</groupId>
          <artifactId>slf4j-api</artifactId>
          <version>1.7.25</version>
        </dependency>
        <!-- https://mvnrepository.com/artifact/org.slf4j/slf4j-simple -->
        <dependency>
          <groupId>org.slf4j</groupId>
          <artifactId>slf4j-simple</artifactId>
          <version>1.7.25</version>
          <scope>test</scope>
        </dependency>
        <dependency>
          <groupId>log4j</groupId>
          <artifactId>log4j</artifactId>
          <version>1.2.12</version>
        </dependency>
        <dependency>
          <groupId>junit</groupId>
          <artifactId>junit</artifactId>
          <version>4.12</version>
        </dependency>
    

      

    2.创建索引

    @Test
        //创建索引
        public void createIndex() throws Exception{
            // 创建Client连接对象
            Settings settings = Settings.builder().put("cluster.name", "my‐elasticsearch").build();
            TransportClient client = new PreBuiltTransportClient(settings).addTransportAddress(
                    new InetSocketTransportAddress(InetAddress.getByName("127.0.0.1"), 9300));
            //创建名称为blog1的索引
            client.admin().indices().prepareCreate("blog1").get();
            //释放资源
            client.close();
        }
    

     

    注意:此时创建的索引是没有mapping映射的

    3.创建映射mapping

    @Test
        //创建映射mapping
        public void createMapping() throws Exception {
            // 创建Client连接
            Settings settings = Settings.builder().put("cluster.name", "my‐elasticsearch").build();
            TransportClient client = new PreBuiltTransportClient(settings).addTransportAddress(
                    new InetSocketTransportAddress(InetAddress.getByName("127.0.0.1"),9300));
            // 添加映射
            /**
             格式:
             "mappings" : {
                "article" : {
                "dynamic" : "false",
                    "properties" : {
                        "id" : { "type" : "string" },
                        "content" : { "type" : "string" },
                        "author" : { "type" : "string" }
                    }
                 }
             }
             */
            XContentBuilder builder = XContentFactory.jsonBuilder()
                    .startObject()
                        .startObject("article")
                            .startObject("properties")
                                .startObject("id")
                                    .field("type", "integer").field("store", "yes")
                                .endObject()
                                .startObject("title")
                                    .field("type", "string").field("store", "yes").field("analyzer", "ik_smart")
                                .endObject()
                                .startObject("content")
                                    .field("type", "string").field("store", "yes").field("analyzer", "ik_smart")
                                .endObject()
                            .endObject()
                        .endObject()
                    .endObject();
            // 创建映射
            PutMappingRequest mapping = Requests.putMappingRequest("blog1")
                    .type("article").source(builder);
            client.admin().indices().putMapping(mapping).get();
            //释放资源
            client.close();
        }
    

      

     

    4.建立文档document

    4.1 建立文档(通过XContentBuilder)

     @Test
        //创建文档(通过XContentBuilder)
        public void createXContentBuilder() throws Exception{
            // 创建Client连接对象
            Settings settings = Settings.builder().put("cluster.name", "my‐elasticsearch").build();
            TransportClient client = new PreBuiltTransportClient(settings)
                    .addTransportAddress(new InetSocketTransportAddress(InetAddress.getByName("127.0.0.1"),
                            9300));
            //创建文档信息
            XContentBuilder builder = XContentFactory.jsonBuilder()
                    .startObject()
                    .field("id", 1)
                    .field("title", "ElasticSearch是一个基于Lucene的搜索服务器")
                    .field("content",
                            "它提供了一个分布式多用户能力的全文搜索引擎,基于RESTful web接口。Elasticsearch是用
    " +
                                    "Java开发的,并作为Apache许可条款下的开放源码发布,是当前流行的企业级搜索引擎。设计用于云计算中,能够达到
    " +
                                    "实时搜索,稳定,可靠,快速,安装使用方便。")
                                    .endObject();
                        // 建立文档对象
                        /**
                         * 参数一blog1:表示索引对象
                         * 参数二article:类型
                         * 参数三1:建立id
                         * */
                     client.prepareIndex("blog1", "article", "1").setSource(builder).get();
                     //释放资源
                     client.close();
        }
    

      

     

    4.2 建立文档(使用Jackson转换实体)

    1)创建Article实体

    package com.wish.elasticSear;
    
    public class Article {
        private Integer id;
        private String title;
        private String content;
    
        public Integer getId() {
            return id;
        }
        public void setId(Integer id) {
            this.id = id;
        }
        public String getTitle() {
            return title;
        }
        public void setTitle(String title) {
            this.title = title;
        }
        public String getContent() {
            return content;
        }
        public void setContent(String content) {
            this.content = content;
        }
    }
    

      

    2)导入Jackson的依赖

        <!-- https://mvnrepository.com/artifact/com.fasterxml.jackson.core/jackson-core -->
        <dependency>
          <groupId>com.fasterxml.jackson.core</groupId>
          <artifactId>jackson-core</artifactId>
          <version>2.8.1</version>
        </dependency>
        <!-- https://mvnrepository.com/artifact/com.fasterxml.jackson.core/jackson-databind -->
        <dependency>
          <groupId>com.fasterxml.jackson.core</groupId>
          <artifactId>jackson-databind</artifactId>
          <version>2.8.1</version>
        </dependency>
        <!-- https://mvnrepository.com/artifact/com.fasterxml.jackson.core/jackson-annotations -->
        <dependency>
          <groupId>com.fasterxml.jackson.core</groupId>
          <artifactId>jackson-annotations</artifactId>
          <version>2.8.1</version>
        </dependency>
    

      

    3)代码实现

    @Test
        //创建文档(通过实体转json)
        public void createJson() throws Exception{
        // 创建Client连接对象
            Settings settings = Settings.builder().put("cluster.name", "my‐elasticsearch").build();
            TransportClient client = new PreBuiltTransportClient(settings)
                    .addTransportAddress(new InetSocketTransportAddress(InetAddress.getByName("127.0.0.1"),
                            9300));
            // 描述json 数据
            //{id:xxx, title:xxx, content:xxx}
            Article article = new Article();
            article.setId(2);
            article.setTitle("搜索工作其实很快乐");
            article.setContent("我们希望我们的搜索解决方案要快,我们希望有一个零配置和一个完全免费的搜索模式,
    " +
                    "                我们希望能够简单地使用JSON通过HTTP的索引数据,我们希望我们的搜索服务器始终可用,我们希望能够一台开始并扩
    " +
                    "                展到数百,我们要实时搜索,我们要简单的多租户,我们希望建立一个云的解决方案。Elasticsearch旨在解决所有这
    " +
                    "                些问题和更多的问题。");
    
            ObjectMapper objectMapper=new ObjectMapper();
            client.prepareIndex(
                    "blog1","article",article.getId().toString()
            ).setSource(
                    objectMapper.writeValueAsString(article).getBytes(),XContentType.JSON
            ).get();
            client.close();
        }
    

      

     

    5.查询文档操作

     5.1关键词查询

     @Test
        //关键词查询
        public void testTermQuery() throws Exception {
            //1、创建es客户端连接对象
            Settings settings = Settings.builder().put("cluster.name", "my‐elasticsearch").build();
            TransportClient client = new PreBuiltTransportClient(settings)
                    .addTransportAddress(new InetSocketTransportAddress(InetAddress.getByName("127.0.0.1"),
                            9300));
            //2、设置搜索条件
            SearchResponse searchResponse = client.prepareSearch("blog1")
                    .setTypes("article")
                    .setQuery(QueryBuilders.termQuery("content", "搜索")).get();
            //3、遍历搜索结果数据
            SearchHits hits = searchResponse.getHits(); // 获取命中次数,查询结果有多少对象
            System.out.println("查询结果有:" + hits.getTotalHits() + "条");
            Iterator<SearchHit> iterator = hits.iterator();
            while (iterator.hasNext()) {
                SearchHit searchHit = iterator.next(); // 每个查询对象
                System.out.println(searchHit.getSourceAsString()); // 获取字符串格式打印
                System.out.println("title:" + searchHit.getSource().get("title"));
            }
            //4、释放资源
            client.close();
        }
    

      

     5.2 字符串查询

     @Test
        //字符串查询
        public void testStringQuery() throws Exception {
            //1、创建es客户端连接对象
            Settings settings = Settings.builder().put("cluster.name", "my‐elasticsearch").build();
            TransportClient client = new PreBuiltTransportClient(settings)
                    .addTransportAddress(new InetSocketTransportAddress(InetAddress.getByName("127.0.0.1"),
                            9300));
            //2、设置搜索条件
            SearchResponse searchResponse = client.prepareSearch("blog1")
                    .setTypes("article")
                    .setQuery(QueryBuilders.queryStringQuery("搜索")).get();
            //3、遍历搜索结果数据
            SearchHits hits = searchResponse.getHits(); // 获取命中次数,查询结果有多少对象
            System.out.println("查询结果有:" + hits.getTotalHits() + "条");
            Iterator<SearchHit> iterator = hits.iterator();
            while (iterator.hasNext()) {
                SearchHit searchHit = iterator.next(); // 每个查询对象
                System.out.println(searchHit.getSourceAsString()); // 获取字符串格式打印
                System.out.println("title:" + searchHit.getSource().get("title"));
            }
            //4、释放资源
            client.close();
    
        }
    

      

     5.3 使用文档ID查询文档

     @Test
        //使用文档ID查询文档
        public void testIdQuery() throws Exception {
            //1、创建es客户端连接对象
            Settings settings = Settings.builder().put("cluster.name", "my‐elasticsearch").build();
            TransportClient client = new PreBuiltTransportClient(settings)
                    .addTransportAddress(new InetSocketTransportAddress(InetAddress.getByName("127.0.0.1"),
                            9300));
            //client对象为TransportClient对象
            SearchResponse response = client.prepareSearch("blog1")
                    .setTypes("article")
            //设置要查询的id
                    .setQuery(QueryBuilders.idsQuery().addIds("1"))
            //执行查询
                    .get();
            //取查询结果
            SearchHits searchHits = response.getHits();
            //取查询结果总记录数
            System.out.println(searchHits.getTotalHits());
            Iterator<SearchHit> hitIterator = searchHits.iterator();
            while(hitIterator.hasNext()) {
                SearchHit searchHit = hitIterator.next();
            //打印整行数据
                System.out.println(searchHit.getSourceAsString());
            }
        }
    

      

    6 .查询文档分页操作

    1)批量插入数据

    @Test
        //批量插入50条数据
        public void continuousInsertion() throws Exception {
            // 创建Client连接对象
            Settings settings = Settings.builder().put("cluster.name", "my‐elasticsearch").build();
            TransportClient client = new PreBuiltTransportClient(settings)
                    .addTransportAddress(new
                            InetSocketTransportAddress(InetAddress.getByName("127.0.0.1"), 9300));
            ObjectMapper objectMapper = new ObjectMapper();
            for (int i = 1; i <= 50; i++) {
                // 描述json 数据
                Article article = new Article();
                article.setId(i);
                article.setTitle(i + "搜索工作其实很快乐");
                article.setContent(i
                        + "我们希望我们的搜索解决方案要快,我们希望有一个零配置和一个完全免费的搜索模式,我
    " +
                        "                    们希望能够简单地使用JSON通过HTTP的索引数据,我们希望我们的搜索服务器始终可用,我们希望能够一台开始并扩展
    " +
                        "                    到数百,我们要实时搜索,我们要简单的多租户,我们希望建立一个云的解决方案。Elasticsearch旨在解决所有这些
    " +
                        "                    问题和更多的问题。");
                // 建立文档
                client.prepareIndex("blog1", "article", article.getId().toString())
                        //.setSource(objectMapper.writeValueAsString(article)).get();
                        .setSource(objectMapper.writeValueAsString(article).getBytes(), XContentType.JSON).get();
               
            }
            //释放资源
            client.close();
        }
    

      

     

    2)分页查询

     @Test
        //分页查询
        public void pagingQuery() throws Exception {
            // 创建Client连接对象
            Settings settings = Settings.builder().put("cluster.name", "my‐elasticsearch").build();
            TransportClient client = new PreBuiltTransportClient(settings)
                    .addTransportAddress(new InetSocketTransportAddress(InetAddress.getByName("127.0.0.1"), 9300));
            // 搜索数据
            SearchRequestBuilder searchRequestBuilder =
                    client.prepareSearch("blog1").setTypes("article")
                            .setQuery(QueryBuilders.matchAllQuery());//默认每页10条记录
            // 查询第2页数据,每页20条
            //setFrom():从第几条开始检索,默认是0。
            //setSize():每页最多显示的记录数。
            searchRequestBuilder.setFrom(0).setSize(5);
            SearchResponse searchResponse = searchRequestBuilder.get();
            SearchHits hits = searchResponse.getHits(); // 获取命中次数,查询结果有多少对象
            System.out.println("查询结果有:" + hits.getTotalHits() + "条");
            Iterator<SearchHit> iterator = hits.iterator();
            while (iterator.hasNext()) {
                SearchHit searchHit = iterator.next(); // 每个查询对象
                System.out.println(searchHit.getSourceAsString()); // 获取字符串格式打印
                System.out.println("id:" + searchHit.getSource().get("id"));
                System.out.println("title:" + searchHit.getSource().get("title"));
                System.out.println("content:" + searchHit.getSource().get("content"));
                System.out.println("‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐");
            }
            //释放资源
            client.close();
        }
    

      

     

     

    7.查询结果高亮操作

    1).什么是高亮显示

    在进行关键字搜索时,搜索出的内容中的关键字会显示不同的颜色,称之为高亮

    2).高亮显示的html分析

     3).高亮显示代码实现

     @Test
        //高亮查询
        public void highlightQuery() throws Exception {
            // 创建Client连接对象
            Settings settings = Settings.builder().put("cluster.name", "my‐elasticsearch").build();
            TransportClient client = new PreBuiltTransportClient(settings)
                    .addTransportAddress(new InetSocketTransportAddress(InetAddress.getByName("127.0.0.1"),
                            9300));
            // 搜索数据
            SearchRequestBuilder searchRequestBuilder = client
                    .prepareSearch("blog1").setTypes("article")
                    .setQuery(QueryBuilders.termQuery("title", "搜索"));
            //设置高亮数据
            HighlightBuilder hiBuilder = new HighlightBuilder();
            hiBuilder.preTags("<font style='color:red'>");
            hiBuilder.postTags("</font>");
            hiBuilder.field("title");
            searchRequestBuilder.highlighter(hiBuilder);
            //获得查询结果数据
            SearchResponse searchResponse = searchRequestBuilder.get();
            //获取查询结果集
            SearchHits searchHits = searchResponse.getHits();
            System.out.println("共搜到:" + searchHits.getTotalHits() + "条结果!");
            //遍历结果
            for (SearchHit hit : searchHits) {
                System.out.println("String方式打印文档搜索内容:");
                System.out.println(hit.getSourceAsString());
                System.out.println("Map方式打印高亮内容");
                System.out.println(hit.getHighlightFields());
                System.out.println("遍历高亮集合,打印高亮片段:");
                Text[] text = hit.getHighlightFields().get("title").getFragments();
                for (Text str : text) {
                    System.out.println(str);
                }
            }
            //释放资源
            client.close();
        }
    

      

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  • 原文地址:https://www.cnblogs.com/wishsaber/p/12372578.html
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