Elasticsearch简单使用系列--使用Java API进行CRUD操作

1.简单介绍Elasticsearch和RDBMS对应的关系,便于记忆理解

Elasticsearch RDBMS index database type/mapping table document/object row/record field column

2.封装一个获取client的工具类

/** * @author lcj * @version 1.0 * @description 获取client * @Create 2017-06-19 */public  class TransportClientUtil {    public static TransportClient getTransportClient(){        Settings settings = Settings.builder()                .put("cluster.name","es-cluster") //设置集群的名字,默认是elasticsearch                .put("client.transport.sniff",true) //启用监听器,每5秒刷新一次nodes                .build();        TransportClient client = null;        try {            client = new PreBuiltTransportClient(settings)            //设置node            //.addTransportAddress(new InetSocketTransportAddress(InetAddress.getByName(System.getenv("COMPUTERNAME")),9300));            .addTransportAddress(new InetSocketTransportAddress(InetAddress.getLocalHost(),9300));        } catch (UnknownHostException e) {            e.printStackTrace();        }        return client;    }}

3.使用java api进行CRUD

/** * @author lcj * @version 1.0 * @description 使用java api操作es node,进行简单的crud * @Create 2017-06-22 */public class EsJavaApi {    private static final Logger LOGGER = LoggerFactory.getLogger(EsJavaApi.class);    private static TransportClient client = TransportClientUtil.getTransportClient();    public static void main(String[] args) {        //创建索引文档        //save();        //搜索文档        //get();        //更新文档        //update();        //删除文档        delete();        //关闭链接        client.close();    }    /**     * pojo bean ,创建index 文档     */    private static void save(){        Book book = new Book();        book.setName("jvm 虚拟机5");        book.setAuthor("lcj4");        book.setPublishTime(new Date().toString());        book.setPrice(512.10);        book.setId("17");        ObjectMapper mapper = new ObjectMapper();        try {            byte[] bytes = mapper.writeValueAsBytes(book);            IndexResponse response = client.prepareIndex("book","book",book.getId())                    .setSource(bytes)                    .get();            System.out.println(response.getResult()); //CREATED        } catch (JsonProcessingException e) {            e.printStackTrace();        }    }    /**     * 根据id,搜索文档     */    private static void get(){        GetResponse response = client.prepareGet("book","book","17")                .setOperationThreaded(false) //默认为true,在不同的线程执行                .get();        //{"id":"17","name":"jvm 虚拟机5","author":"lcj4","price":512.1,"publishTime":"Thu Jun 22 13:36:49 CST 2017"}        System.out.println(response.getSourceAsString());    }    /**     * 更新文档     */    private static void update(){        UpdateRequest updateRequest = new UpdateRequest();        //指定索引        updateRequest.index("book");        //指定类型        updateRequest.type("book");        //指定id        updateRequest.id("17");        Book book = new Book();        book.setName("jvm 虚拟机55");        book.setAuthor("lcj4");        book.setPublishTime(DateFormatUtils.format(new Date(),"yyyy-MM-dd HH:mm:ss"));        book.setPrice(512.18);        book.setId("17");        ObjectMapper mapper = new ObjectMapper();        //有很多重载方法        //{"_index":"book","_type":"book","_id":"17","_version":2,"found":true,"_source":{"id":"17","name":"jvm 虚拟机55","author":"lcj4","price":512.18,"publishTime":"2017-06-22 13:45:22"}}        try {            updateRequest.doc(mapper.writeValueAsBytes(book));            client.update(updateRequest).get();        } catch (Exception e) {            e.printStackTrace();        }    }    /*根据id删除文档*/    private static void delete(){        DeleteResponse response = client.prepareDelete("book","book","17")                .get();        //DeleteResponse[index=book,type=book,id=17,version=3,result=deleted,shards=ShardInfo{total=2, successful=1, failures=[]}]        System.out.println(response);    }}