Dubbo介绍
Dubbo是一款高性能、轻量级的开源Java RPC框架,它提供了三大核心能力:面向接口的远程方法调用,智能容错和负载均衡,以及服务自动注册和发现。
核心部件功能
Remoting: 网络通信框架,实现了 sync-over-async 和
request-response 消息机制.
RPC: 一个远程过程调用的抽象,支持负载均衡、容灾和集群功能
Registry: 服务目录框架用于服务的注册和服务事件发布和订阅
工作原理
特性
- 面向接口代理的高性能RPC调用
提供高性能的基于代理的远程调用能力,服务以接口为粒度,为开发者屏蔽远程调用底层细节。
- 智能负载均衡
内置多种负载均衡策略,智能感知下游节点健康状况,显著减少调用延迟,提高系统吞吐量。
- 服务自动注册与发现
支持多种注册中心服务,服务实例上下线实时感知。
- 高度可扩展能力
遵循微内核+插件的设计原则,所有核心能力如Protocol、Transport、Serialization被设计为扩展点,平等对待内置实现和第三方实现。
- 运行期流量调度
内置条件、脚本等路由策略,通过配置不同的路由规则,轻松实现灰度发布,同机房优先等功能。
- 可视化的服务治理与运维
提供丰富服务治理、运维工具:随时查询服务元数据、服务健康状态及调用统计,实时下发路由策略、调整配置参数。
案例:
首先下载zookeeper(下载地址https://mirrors.tuna.tsinghua.edu.cn/apache/zookeeper/)解压到本地。启动Zookeeper注册中心,在解压后zookeeper-3.4.11文件夹bin下启动cmd,输入zkServer.cmd
若启动注册中心失败,则需要修改conf目录下zoo.cfg文件,如图。
启动dubbo监控中心,通过java -jar jar包名命令启动。jar包下载地址:链接:https://pan.baidu.com/s/1m_4ktW19muxPKWpdKbufVQ 提取码:xy35
通过浏览器访问监控中心,访问时要输入用户名:root与密码:root:
1.新建maven项目user-service-gmall,该项目包含了bean类、与接口(OrderService、UserService)
UserAddress类:
public class UserAddress implements Serializable { private Integer id; private String userAddress; //用户地址 private String userId; //用户id private String consignee; //收货人 private String phoneNum; //电话号码 private String isDefault; //是否为默认地址 Y-是 N-否 public UserAddress() { super(); // TODO Auto-generated constructor stub } public UserAddress(Integer id, String userAddress, String userId, String consignee, String phoneNum, String isDefault) { super(); this.id = id; this.userAddress = userAddress; this.userId = userId; this.consignee = consignee; this.phoneNum = phoneNum; this.isDefault = isDefault; } public Integer getId() { return id; } public void setId(Integer id) { this.id = id; } public String getUserAddress() { return userAddress; } public void setUserAddress(String userAddress) { this.userAddress = userAddress; } public String getUserId() { return userId; } public void setUserId(String userId) { this.userId = userId; } public String getConsignee() { return consignee; } public void setConsignee(String consignee) { this.consignee = consignee; } public String getPhoneNum() { return phoneNum; } public void setPhoneNum(String phoneNum) { this.phoneNum = phoneNum; } public String getIsDefault() { return isDefault; } public void setIsDefault(String isDefault) { this.isDefault = isDefault; } }
OrderService接口:
public interface OrderService { /** * 初始化订单 * @param userId */ public List<UserAddress> initOrder(String userId); }
UserService接口:
public interface UserService { /** * 按照用户id返回所有的收货地址 * @param userId * @return */ public List<UserAddress> getUserAddressList(String userId); }
2.创建user-service-provider01项目
pom文件中添加maven依赖:添加user-service-gmall项目依赖
<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/xsd/maven-4.0.0.xsd"> <modelVersion>4.0.0</modelVersion> <groupId>com.moon</groupId> <artifactId>user-service-provider01</artifactId> <version>0.0.1-SNAPSHOT</version> <dependencies> <dependency> <groupId>com.moon</groupId> <artifactId>user-service-gmall</artifactId> <version>0.0.1-SNAPSHOT</version> </dependency> <dependency> <groupId>com.alibaba</groupId> <artifactId>dubbo</artifactId> <version>2.6.2</version> </dependency> <!-- 注册中心使用的是zookeeper,引入操作zookeeper的客户端端 --> <dependency> <groupId>org.apache.curator</groupId> <artifactId>curator-framework</artifactId> <version>2.12.0</version> </dependency> </dependencies> </project>
UserServiceImpl类
public class UserServiceImpl implements UserService { @Override public List<UserAddress> getUserAddressList(String userId) { // TODO Auto-generated method stub System.out.println("UserServiceImpl..3....."); UserAddress address1 = new UserAddress(1, "陕西省西安市", "1", "dd", "010-56253825", "Y"); UserAddress address2 = new UserAddress(2, "陕西省咸阳市", "1", "dd", "010-56253825", "N"); return Arrays.asList(address1,address2); } }
RunClass类
public class MainClass { public static void main(String[] args) throws Exception{ System.out.println("开启服务"); ClassPathXmlApplicationContext ioc = new ClassPathXmlApplicationContext("provider.xml"); ioc.start(); System.in.read(); } }
provider.xml
<?xml version="1.0" encoding="UTF-8"?> <beans xmlns="http://www.springframework.org/schema/beans" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:dubbo="http://code.alibabatech.com/schema/dubbo" xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd http://dubbo.apache.org/schema/dubbo http://dubbo.apache.org/schema/dubbo/dubbo.xsd http://code.alibabatech.com/schema/dubbo http://code.alibabatech.com/schema/dubbo/dubbo.xsd"> <!-- 1、指定当前服务/应用的名字(同样的服务名字相同,不要和别的服务同名) --> <dubbo:application name="user-service-provider01"></dubbo:application> <!-- 2、指定注册中心的位置 --> <!-- <dubbo:registry address="zookeeper://127.0.0.1:2181"></dubbo:registry> --> <dubbo:registry protocol="zookeeper" address="127.0.0.1:2181"></dubbo:registry> <!-- 3、指定通信规则(通信协议?通信端口) --> <dubbo:protocol name="dubbo" port="20882"></dubbo:protocol> <bean id="userServiceImpl" class="com.moon.service.UserServiceImpl"></bean> <!-- 4、暴露服务 ref:指向服务的真正的实现对象 --> <dubbo:service interface="com.moon.user_service_gmall.service.UserService" ref="userServiceImpl" timeout="1000" version="2.0.0"> <dubbo:method name="getUserAddressList" timeout="1000"></dubbo:method> </dubbo:service> </beans>
3.创建user-service-consumer项目
OrderServiceImpl类
@Service public class OrderServiceImpl implements OrderService{ @Autowired UserService userService; public List<UserAddress> initOrder(String userId) { // TODO Auto-generated method stub List<UserAddress> addressList = userService.getUserAddressList(userId); for (UserAddress userAddress : addressList) { System.out.println(userAddress.getUserAddress()+"---"+userAddress.getId()); } return addressList; } }
启动类MainClass
@SuppressWarnings("resource") public class MainClass { public static void main(String[] args) { ClassPathXmlApplicationContext c = new ClassPathXmlApplicationContext("consumer.xml"); c.start(); OrderService orderService = (OrderService) c.getBean(OrderService.class); orderService.initOrder("1"); System.out.println("调用完成...."); try { System.in.read(); } catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); } } }
consumer.xml配置文件
<?xml version="1.0" encoding="UTF-8"?> <beans xmlns="http://www.springframework.org/schema/beans" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:dubbo="http://dubbo.apache.org/schema/dubbo" xmlns:context="http://www.springframework.org/schema/context" xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-4.3.xsd http://dubbo.apache.org/schema/dubbo http://dubbo.apache.org/schema/dubbo/dubbo.xsd http://code.alibabatech.com/schema/dubbo http://code.alibabatech.com/schema/dubbo/dubbo.xsd"> <context:component-scan base-package="com.moon.service"></context:component-scan> <dubbo:application name="order-service-consumer"></dubbo:application> <dubbo:registry address="zookeeper://127.0.0.1:2181"></dubbo:registry> <!-- timeout="0" 默认是1000ms--> <!-- retries="":重试次数,不包含第一次调用,0代表不重试--> <!-- 幂等(设置重试次数)【查询、删除、修改】、非幂等(不能设置重试次数)【新增】 --> <dubbo:reference interface="com.moon.user_service_gmall.service.UserService" <!--在user-service-provider中暴露的接口服务 --> id="userService" timeout="5000" retries="3" version="*"> <!-- <dubbo:method name="getUserAddressList" timeout="1000"></dubbo:method> --> </dubbo:reference> </beans>
4.启动服务提供者与消费者,即启动user-service-provider01与user-service-consumer中MainClass中的main方法(先启动服务提供者)。
访问Dubbo后台监控系统,如图。
原文地址:https://www.cnblogs.com/menbo/p/10956900.html