SpringCloud調用服務示例。
SpringCloud简介:
Spring Cloud是一系列框架的有序集合。它利用Spring Boot的开发便利性巧妙地简化了分布式系统基础设施的开发,如服务发现注册、配置中心、消息总线、负载均衡、断路器、数据监控等,都可以用Spring Boot的开发风格做到一键启动和部署。Spring并没有重复制造轮子,它只是将目前各家公司开发的比较成熟、经得起实际考验的服务框架组合起来,通过Spring Boot风格进行再封装屏蔽掉了复杂的配置和实现原理,最终给开发者留出了一套简单易懂、易部署和易维护的分布式系统开发工具包。
SpringCloud与Springboot内部以及集成好了,可以直接使用SpringBoot.
使用SpringCloud的调用需要新建三个maven项目,分别为eureka-server(服务注册中心) server-member(服务提供方) server-order(服务消费方)
(1)maven项目 eureka-server ,服务注册方(类似于dubbo中使用的 zookeeper)
项目目录结构如下: 需要编写的三个文件(EurekaApp.java application.yml pom.xml)
EurekaApp.java SpringBoot的启动类,主要用于启动项目,读取配置文件信息
记得要添加注解 @EnableEurekaServer
package springcloud.eureka_server.demo;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.netflix.eureka.server.EnableEurekaServer;
/**
* springcloud的注册中心
* @author Administrator
* 启动后,在浏览器通过 localhost:8888访问
*/
@SpringBootApplication
@EnableEurekaServer
public class EurekaApp {
public static void main(String[] args){
SpringApplication.run(EurekaApp.class, args);
}
}
application.yml
port
defaultZone
server:
port: 8888 # 指定该Eureka实例的端口
eureka:
instance:
hostname: localhost
client:
registerWithEureka: false
fetchRegistry: false
serviceUrl:
defaultZone: http://${eureka.instance.hostname}:${server.port}/eureka/
pom.xml Springboot与SpringCloud的依赖文件
<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/maven-v4_0_0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>springcloud</groupId>
<artifactId>eureka-server</artifactId>
<packaging>war</packaging>
<version>0.0.1-SNAPSHOT</version>
<name>eureka-server Maven Webapp</name>
<url>http://maven.apache.org</url>
<!-- 引入spring boot的依赖 -->
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>1.4.3.RELEASE</version>
</parent>
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<java.version>1.7</java.version>
</properties>
<dependencies>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-eureka-server</artifactId>
</dependency>
</dependencies>
<!-- 引入spring cloud的依赖 -->
<dependencyManagement>
<dependencies>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-dependencies</artifactId>
<version>Camden.SR4</version>
<type>pom</type>
<scope>import</scope>
</dependency>
</dependencies>
</dependencyManagement>
<!-- 添加spring-boot的maven插件 -->
<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
</plugin>
</plugins>
</build>
</project>
启动项目
运行EurekaApp.java ,Run as --- >> Java Application
启动成功后,在浏览器访问: http://localhost:8888
访问结果如下图所示:
(2)maven项目server-member ,服务提供方 (类似dubbo的provider)
项目目录结构如下,需要编写的文件有四个(MemberApp.java Member.controller.java application.yml pom.xml)
MemberController.java 服务提供方的前端控制器类
@RestController
@RequestMapping
package springcloud.server_member.demo.controller;
import java.util.ArrayList;
import java.util.List;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
/**
* 会员服务
* @author Administrator
*
*/
@RestController
public class MemberController {
@RequestMapping("/getMember")
public List<String> getMember(){
List<String> list = new ArrayList<String>();
list.add("zhangsan");
list.add("zhangsan1");
list.add("zhangsan2");
list.add("zhangsan3");
return list;
}
}
MemberApp.java 项目的SpringBoot启动类
记得使用 @EnableEurekaClient 注解 标明这是一个服务Client,需要注册在eureka上的一个服务
package springcloud.server_member.demo;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.netflix.eureka.EnableEurekaClient;
/**
* 启动会员服务
* @author Administrator
*
* 服务的调用: reset feign
*/
@SpringBootApplication
@EnableEurekaClient
public class MemberApp {
public static void main(String[] args){
SpringApplication.run(MemberApp.class, args);
}
}
application.yml SpringCloud的配置文件
server.port 定义访问的端口
spring.application.name 定义服务名,在服务消费方通过这个服务名调用服务!(很重要哦)
eureka:
client:
serviceUrl:
defaultZone: http://localhost:8888/eureka/
server:
port: 8762
spring:
application:
name: server-member
pom.xml SpringCloud与SpringBoot的包依赖
<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/maven-v4_0_0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>springcloud</groupId>
<artifactId>server-member</artifactId>
<packaging>war</packaging>
<version>0.0.1-SNAPSHOT</version>
<name>server-member Maven Webapp</name>
<url>http://maven.apache.org</url>
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>1.4.3.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>1.7</java.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>
<dependency>
<groupId>org.objenesis</groupId>
<artifactId>objenesis</artifactId>
<version>1.2</version>
</dependency>
</dependencies>
<dependencyManagement>
<dependencies>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-dependencies</artifactId>
<version>Dalston.RC1</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>
启动项目 (这个项目启动前需要先启动 eureka-server项目)
运行MemberApp.java ,Run as --- >> Java Application
启动成功后,在浏览器访问: http://localhost:8762/getMember
访问结果如下图所示:
同时再次访问服务注册中心 eureka-server项目,会出现如下结果,Instance下厨多出一行服务
(3)maven项目 server-order 服务消费方(类似dubbo的customer)
项目目录结构如下: 需要编写的文件有五个(OrderController.java OrderService.java OrderApp.java application.yml pom.xml)
OrderService.java 服务消费方的业务类,在这里调用服务提供方的服务
RestTemplate 是框架中定义的rest服务调用
restTemplate.getForObject("http://server-member/getMember", List.class); 这是调用服务名为 server-member的服务中的 getMember请求对应的方法 (这里与上一个maven项目server-member项目中的配置相对应)
package springcloud.server_order.demo.service;
import java.util.ArrayList;
import java.util.List;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import org.springframework.web.client.RestTemplate;
@Service
public class OrderService {
@Autowired
private RestTemplate restTemplate;
/**
* http: 这里是写member-server里面的访问路径。 getMember是访问方法
* @return
*/
public List<String> getAllUser(){
return restTemplate.getForObject("http://server-member/getMember", List.class);
}
}
OrderController.java 服务消费者的前端控制类。
使用@Autowired注解 注入业务层对象,调用业务层方法
package springcloud.server_order.demo.controller;
import java.util.List;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
import springcloud.server_order.demo.service.OrderService;
@RestController
public class OrderController {
@Autowired
private OrderService orderService;
@RequestMapping("/getOrderUser")
public List<String> getAllUser(){
System.out.println("订单服务正在测试会议服务");
return orderService.getAllUser();
}
}
OrderApp.java 项目的SpringBoot启动类
@EnableEurekaClient
@LoadBalanced 标识服务的调用,需要用到负载均衡
package springcloud.server_order.demo;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.client.loadbalancer.LoadBalanced;
import org.springframework.cloud.netflix.eureka.EnableEurekaClient;
import org.springframework.context.annotation.Bean;
import org.springframework.web.client.RestTemplate;
@SpringBootApplication
@EnableEurekaClient
public class OrderApp {
public static void main(String[] args){
SpringApplication.run(OrderApp.class, args);
}
/**
* 表示支持负载均衡
* @return
*/
@Bean
@LoadBalanced
RestTemplate restTemplate() {
return new RestTemplate();
}
}
application.yml Springcloud的配置文件
eureka.client.serviceUrl.defaultZone 注册中心的地址
server.port 访问服务的端口
spring.application.name 服务名称
eureka:
client:
serviceUrl:
defaultZone: http://localhost:8888/eureka/
server:
port: 8764
spring:
application:
name: server-order
pom.xml
<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/maven-v4_0_0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>springcloud</groupId>
<artifactId>server-order</artifactId>
<packaging>war</packaging>
<version>0.0.1-SNAPSHOT</version>
<name>server-order Maven Webapp</name>
<url>http://maven.apache.org</url>
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>1.5.2.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>
</properties>
<dependencies>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-eureka</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-ribbon</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>
<dependency>
<groupId>org.objenesis</groupId>
<artifactId>objenesis</artifactId>
<version>1.2</version>
</dependency>
</dependencies>
<dependencyManagement>
<dependencies>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-dependencies</artifactId>
<version>Dalston.RC1</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>
启动项目(启动这个项目之前需要先启动 eureka-server server-member)
运行OrderApp.java ,Run as --- >> Java Application
启动成功后,在浏览器访问: http://localhost:8764/getOrderUser
访问结果如下图所示: