spring boot集成elasticsearch并实现简单的增删改查

java操作elasticsearch是作为一个无数据节点与其他节点之间通信，因此使用的是tcp端口，elasticsearch默认的节点间通信的tcp端口是9300。elasticsearch和jdk版本一定要适配，因为elasticsearch是用java编写的，随着版本的升级，用的也是最新版的jdk，所以低版本的jdk就和最新elasticsearch版本不匹配。但是，高版本的jdk可以向下兼容低版本的elasticsearch，因为jdk在升级的过程中，自身也要向下兼容。这一点很重要，否则项目是起不来的。我用的是jdk1.8,elasticsearch-2.4.2。现在，让我们开始集成。

一、注入elasticsearch依赖

 <!-- elasticsearch -->
    <dependency>
            <groupId>org.elasticsearch</groupId>
            <artifactId>elasticsearch</artifactId>
            <!-- <version>6.0.0</version> -->
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-data-elasticsearch</artifactId>
        </dependency>
         
        <dependency>
            <groupId>org.springframework.data</groupId>
            <artifactId>spring-data-elasticsearch</artifactId>
        </dependency>
        <dependency>  
            <groupId>com.fasterxml.jackson.core</groupId>  
            <artifactId>jackson-databind</artifactId>  
            <!-- <version>2.1.3</version>   -->
		 </dependency>
		 <dependency>
            <groupId>net.java.dev.jna</groupId>
            <artifactId>jna</artifactId>
            <!-- <version>3.0.9</version> -->
        </dependency>

二、在application.properties中添加elasticsearch配置

# elasticsearch
#节点名字，默认elasticsearch
spring.data.elasticsearch.cluster-name=elasticsearch
#节点地址，多个节点用逗号隔开
spring.data.elasticsearch.cluster-nodes=127.0.0.1:9300
#spring.data.elasticsearch.local=false
spring.data.elasticsearch.repositories.enable=true

三、实体类

import org.springframework.data.annotation.Id;
import org.springframework.data.elasticsearch.annotations.Document;
import org.springframework.data.elasticsearch.annotations.Field;
 
// indexName ：索引名字（对应mysql的数据库名字）
//type:类型（对应mysql的表名）
@Document(indexName = "megacorp",type = "employee", shards = 1,replicas = 0, refreshInterval = "-1")
public class Employee {
    @Id
    private String id;
    @Field
    private String firstName;
    @Field
    private String lastName;
    @Field
    private Integer age=0;
    @Field
    private String about;
    //get、set...
}

四、编写dao

import org.springframework.data.elasticsearch.repository.ElasticsearchRepository;
import org.springframework.stereotype.Component;
 
import com.example.demo.elasticsearch.entity.Employee;
 
@Component
public interface EmployeeRepository extends ElasticsearchRepository<Employee,String>{
	
	Employee queryEmployeeById(String id);
 
}

五、由于咱们就是入门测试，service我就省略了，直接书写接口了

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
 
import com.example.demo.elasticsearch.dao.EmployeeRepository;
import com.example.demo.elasticsearch.entity.Employee;
import com.google.gson.Gson;
 
@RestController
@RequestMapping("/es")
public class ElasticSearchController {
	
    @Autowired
    private EmployeeRepository er;
	
	//增加
	@RequestMapping("/add")
	public String add(){
		
		Employee employee=new Employee();
		employee.setId("1");
		employee.setFirstName("xuxu");
		employee.setLastName("zh");
		employee.setAge(26);
		employee.setAbout("i am in peking");
		er.save(employee);
		
		System.err.println("add a obj");
		
		return "success";
	}
	
        //删除
	@RequestMapping("/delete")
	public String delete(){
		
		er.delete("1");
		
		return "success";
	}
	
        //局部更新
	@RequestMapping("/update")
	public String update(){
		
		Employee employee=er.queryEmployeeById("1");
		employee.setFirstName("哈哈");
		er.save(employee);
		
		System.err.println("update a obj");
	
		return "success";
	}
	
        //查询
	@RequestMapping("/query")
	public Employee query(){
		
		Employee accountInfo=er.queryEmployeeById("1");
		System.err.println(new Gson().toJson(accountInfo));
		
		return accountInfo;
	}
	
}

至此，elasticsearch就算是入门了。

参考文献：https://blog.csdn.net/zhaoyahui_666/article/details/78688688