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

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);
}
}