一、 eureka client说明：

Eureka客户端是一个java客户端，用来简化与服务器的交互、作为轮询负载均衡器，并提供服务的故障切换支持。Netflix在其生产环境中使用的是另外的客户端，它提供基于流量、资源利用率以及出错状态的加权负载均衡

二、创建一个服务提供者

0.项目结构:

image.png

创建一个像cloud-client项目，创建完pom.xml文件如下:

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>

    <groupId>com.cloud.client</groupId>
    <artifactId>client</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <packaging>jar</packaging>

    <name>client</name>
    <description>this spring-boot client</description>

    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>1.5.9.RELEASE</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>

    <properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
        <java.version>1.8</java.version>
        <spring-cloud.version>Edgware.RELEASE</spring-cloud.version>
    </properties>

    <dependencies>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-eureka</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
    </dependencies>

    <dependencyManagement>
        <dependencies>
            <dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-dependencies</artifactId>
                <version>${spring-cloud.version}</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>
        </dependencies>
    </dependencyManagement>


    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>

    <repositories>
        <repository>
            <id>spring-milestones</id>
            <name>Spring Milestones</name>
            <url>https://repo.spring.io/milestone</url>
            <snapshots>
                <enabled>false</enabled>
            </snapshots>
        </repository>
    </repositories>
</project>

2.application.properties 配置文件如下：
spring.application.name:这个名字很重要的，以后服务与服务之间调用根据这个名字
eureka.client.serviceUrl.defaultZone:服务注册中心

server.port=8762
spring.application.name=service-hi
eureka.client.serviceUrl.defaultZone=http://localhost:8761/eureka/

2.通过注解@EnableEurekaClient表明自己是一个eurekaclient


@SpringBootApplication
@EnableEurekaClient
public class ClientApplication {

    public static void main(String[] args) {
        SpringApplication.run(ClientApplication.class, args);
    }
}

3.创建一个controller包下面创建一个 TestController

@RestController
public class TestController {

    @Value("${server.port}")
    String port;

    @RequestMapping("/hi")
    @ResponseBody
    public String home(@RequestParam String name) {
        return "hi "+name+",i am from port:" +port;
    }

}

4：打开浏览器：输入服务注册中心:http://localhost:8761，这时候出现一个服务提供者：