ElasticSearch编程操作

ElasticSearch编程操作
1.1 创建工程，导入坐标

pom.xml坐标

xml 复制代码

<dependencies>
    <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>
    <dependency>
        <groupId>org.apache.logging.log4j</groupId>
        <artifactId>log4j-to-slf4j</artifactId>
        <version>2.9.1</version>
    </dependency>
    <dependency>
        <groupId>org.slf4j</groupId>
        <artifactId>slf4j-api</artifactId>
        <version>1.7.24</version>
    </dependency>
    <dependency>
        <groupId>org.slf4j</groupId>
        <artifactId>slf4j-simple</artifactId>
        <version>1.7.21</version>
    </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>
</dependencies>

1.2 创建索引index

java 复制代码

@Test
//创建索引
public void test1() 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blog2的索引
    client.admin().indices().prepareCreate("blog2").get();
    //释放资源
    client.close();
}

1.3 创建映射mapping

java 复制代码

@Test
//创建映射
public void test3() 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));
    
    // 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("blog2")
        .type("article").source(builder);
    client.admin().indices().putMapping(mapping).get();
    //释放资源
    client.close();
}

1.4 建立文档document
1.4.1 建立文档（通过XContentBuilder）

java 复制代码

@Test
//创建文档(通过XContentBuilder)
public void test4() 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("blog2", "article", "1").setSource(builder).get();

    //释放资源
    client.close();
}

1.4.2 建立文档（使用Jackson转换实体）

1）创建Article实体

java 复制代码

public class Article {
	private Integer id;
	private String title;
	private String content;
    getter/setter...
}

2）添加jackson坐标

xml 复制代码

<dependency>
    <groupId>com.fasterxml.jackson.core</groupId>
    <artifactId>jackson-core</artifactId>
    <version>2.8.1</version>
</dependency>
<dependency>
    <groupId>com.fasterxml.jackson.core</groupId>
    <artifactId>jackson-databind</artifactId>
    <version>2.8.1</version>
</dependency>
<dependency>
    <groupId>com.fasterxml.jackson.core</groupId>
    <artifactId>jackson-annotations</artifactId>
    <version>2.8.1</version>
</dependency>

3）代码实现

java 复制代码

@Test
//创建文档(通过实体转json)
public void test5() 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();

    // 建立文档
    client.prepareIndex("blog2", "article", article.getId().toString())
        //.setSource(objectMapper.writeValueAsString(article)).get();
        .setSource(objectMapper.writeValueAsString(article).getBytes(), XContentType.JSON).get();

    //释放资源
    client.close();
}

1.5 查询文档操作

1.5.1关键词查询

java 复制代码

@Test
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("blog2")
        .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();

}

1.5.2 字符串查询

java 复制代码

@Test
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("blog2")
        .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();

}

1.5.3 使用文档ID查询文档

java 复制代码

@Test
    public void testIdQuery() throws Exception {
        //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("test002"))
                //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());
        }
    }

1.6 查询文档分页操作

1.6.1 批量插入数据

java 复制代码

 @Test
//批量插入100条数据
public void test9() 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 <= 100; 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("blog2", "article", article.getId().toString())
                    //.setSource(objectMapper.writeValueAsString(article)).get();
                    .setSource(objectMapper.writeValueAsString(article).getBytes(),XContentType.JSON).get();
        }

        //释放资源
        client.close();
}

1.6.2 分页查询

java 复制代码

@Test
//分页查询
public void test10() 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("blog2").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();
}

1.7 查询结果高亮操作

高亮显示代码实现

java 复制代码

@Test
//高亮查询
public void test11() 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("blog2").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();
}