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\n" +
                                "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\n" +
                                "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，\n" +
                "                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\n" +
                "                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\n" +
                "                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\n" +
                    "                    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\n" +
                    "                    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\n" +
                    "                    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();
    }