架构师系列-搜索引擎ElasticSearch（三）- Java API

SpringBoot整合ES

搭建SpringBoot工程，引入ElasticSearch相关坐标

XML 复制代码

 <!--引入es的坐标-->
        <dependency>
            <groupId>org.elasticsearch.client</groupId>
            <artifactId>elasticsearch-rest-high-level-client</artifactId>
            <version>7.4.0</version>
        </dependency>
        <dependency>
            <groupId>org.elasticsearch.client</groupId>
            <artifactId>elasticsearch-rest-client</artifactId>
            <version>7.4.0</version>
        </dependency>
        <dependency>
            <groupId>org.elasticsearch</groupId>
            <artifactId>elasticsearch</artifactId>
            <version>7.4.0</version>
        </dependency>

测试

ElasticSearchConfig.java

java 复制代码

@Configuration
@ConfigurationProperties(prefix = "elasticsearch")
public class ElasticSearchConfig {
    private String host;
    private int port;

    public String getHost() {
        return host;
    }

    public void setHost(String host) {
        this.host = host;
    }

    public int getPort() {
        return port;
    }

    public void setPort(int port) {
        this.port = port;
    }

    @Bean
    public RestHighLevelClient client(){
        return new RestHighLevelClient(RestClient.builder(
                new HttpHost(
                        host,
                        port,
                        "http"
                )
        ));
    }
}

java 复制代码

@SpringBootTest
class ElasticsearchDemoApplicationTests {

    @Autowired
    private RestHighLevelClient client;

    @Test
    void contextLoads() {
       /* //1.创建ES客户端对象
        RestHighLevelClient client = new RestHighLevelClient(RestClient.builder(
           new HttpHost(
                   "192.168.149.135",
                   9200,
                   "http"
           )
        ));*/

        System.out.println(client);


    }

创建索引

添加索引

java 复制代码

/**
     * 添加索引
     */
    @Test
    public void addIndex() throws IOException {
        //1.使用client获取操作索引的对象
        IndicesClient indicesClient = client.indices();
        //2.具体操作，获取返回值
        CreateIndexRequest createRequest = new CreateIndexRequest("itheima");
        CreateIndexResponse response = indicesClient.create(createRequest, RequestOptions.DEFAULT);

        //3.根据返回值判断结果
        System.out.println(response.isAcknowledged());
    }

添加索引，并添加映射

java 复制代码

/**
     * 添加索引
     */
    @Test
    public void addIndexAndMapping() throws IOException {
        //1.使用client获取操作索引的对象
        IndicesClient indicesClient = client.indices();
        //2.具体操作，获取返回值
        CreateIndexRequest createRequest = new CreateIndexRequest("itcast");
        //2.1 设置mappings
        String mapping = "{\n" +
                "      \"properties\" : {\n" +
                "        \"address\" : {\n" +
                "          \"type\" : \"text\",\n" +
                "          \"analyzer\" : \"ik_max_word\"\n" +
                "        },\n" +
                "        \"age\" : {\n" +
                "          \"type\" : \"long\"\n" +
                "        },\n" +
                "        \"name\" : {\n" +
                "          \"type\" : \"keyword\"\n" +
                "        }\n" +
                "      }\n" +
                "    }";
        createRequest.mapping(mapping,XContentType.JSON);
        CreateIndexResponse response = indicesClient.create(createRequest, RequestOptions.DEFAULT);
        //3.根据返回值判断结果
        System.out.println(response.isAcknowledged());
    }

查询、删除、判断索引

java 复制代码

 /**
     * 查询索引
     */
    @Test
    public void queryIndex() throws IOException {
        IndicesClient indices = client.indices();
        GetIndexRequest getReqeust = new GetIndexRequest("itcast");
        GetIndexResponse response = indices.get(getReqeust, RequestOptions.DEFAULT);
        //获取结果
        Map<String, MappingMetaData> mappings = response.getMappings();
        for (String key : mappings.keySet()) {
            System.out.println(key+":" + mappings.get(key).getSourceAsMap());
        }
    }

    /**
     * 删除索引
     */
    @Test
    public void deleteIndex() throws IOException {
        IndicesClient indices = client.indices();
        DeleteIndexRequest deleteRequest = new DeleteIndexRequest("itheima");
        AcknowledgedResponse response = indices.delete(deleteRequest, RequestOptions.DEFAULT);
        System.out.println(response.isAcknowledged());
    }

    /**
     * 判断索引是否存在
     */
    @Test
    public void existIndex() throws IOException {
        IndicesClient indices = client.indices();
        GetIndexRequest getRequest = new GetIndexRequest("itcast");
        boolean exists = indices.exists(getRequest, RequestOptions.DEFAULT);
        System.out.println(exists);
    }

添加文档

添加文档使用map作为数据

java 复制代码

 /**
     * 添加文档,使用map作为数据
     */
    @Test
    public void addDoc() throws IOException {
        //数据对象，map
        Map data = new HashMap();
        data.put("address","北京昌平");
        data.put("name","大胖");
        data.put("age",20);

        //1.获取操作文档的对象
        IndexRequest request = new IndexRequest("itcast").id("1").source(data);
        //添加数据，获取结果
        IndexResponse response = client.index(request, RequestOptions.DEFAULT);

        //打印响应结果
        System.out.println(response.getId());

    }

添加文档使用对象作为数据

java 复制代码

/**
     * 添加文档,使用对象作为数据
     */
    @Test
    public void addDoc2() throws IOException {
        //数据对象，javaObject
        Person p = new Person();
        p.setId("2");
        p.setName("小胖2222");
        p.setAge(30);
        p.setAddress("陕西西安");
        //将对象转为json
        String data = JSON.toJSONString(p);
        //1.获取操作文档的对象
        IndexRequest request = new IndexRequest("itcast").id(p.getId()).source(data,XContentType.JSON);
        //添加数据，获取结果
        IndexResponse response = client.index(request, RequestOptions.DEFAULT);
        //打印响应结果
        System.out.println(response.getId());
    }


public class Person {
    private String id;
    private String name;
    private int age;
    private String address;



    public String getId() {
        return id;
    }

    public void setId(String id) {
        this.id = id;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public int getAge() {
        return age;
    }

    public void setAge(int age) {
        this.age = age;
    }

    public String getAddress() {
        return address;
    }

    public void setAddress(String address) {
        this.address = address;
    }

    @Override
    public String toString() {
        return "Person{" +
                "id='" + id + '\'' +
                ", name='" + name + '\'' +
                ", age=" + age +
                ", address='" + address + '\'' +
                '}';
    }
}

修改、查询、删除文档

修改文档

java 复制代码

  /**
     * 修改文档：添加文档时，如果id存在则修改，id不存在则添加
     */
    @Test
    public void updateDoc() throws IOException {
        Person person=new Person();
        person.setId("2");
        person.setName("李四");
        person.setAge(20);
        person.setAddress("北京三环车王");
        String data = JSON.toJSONString(person);
        IndexRequest request = new IndexRequest("itcast").id(person.getId()).source(data,XContentType.JSON);
        IndexResponse response = client.index(request, RequestOptions.DEFAULT);
        System.out.println(response.getId());
    }

查询文档

java 复制代码

/**
     * 根据id查询文档
     */
    @Test
    public void findDocById() throws IOException {
        GetRequest getReqeust = new GetRequest("itcast","1");
        //getReqeust.id("1");
        GetResponse response = client.get(getReqeust, RequestOptions.DEFAULT);
        //获取数据对应的json
        System.out.println(response.getSourceAsString());
    }

删除文档

java 复制代码

/**
     * 根据id删除文档
     */
    @Test
    public void delDoc() throws IOException {


        DeleteRequest deleteRequest = new DeleteRequest("itcast","1");
        DeleteResponse response = client.delete(deleteRequest, RequestOptions.DEFAULT);
        System.out.println(response.getId());


    }