jar包只可调用，无法直接启动使用？Nocas篇之. 配置中心实战（一）

1. 配置中心实战

配置中心在项目中的作用是什么？赶快来体验一把吧！Let’s go!

1.1 实现步骤

•步骤一：编写user测试服务：添加数据 --> clouddb5.tuser
•步骤二:将程序打包jar包，运行jar包
•步骤三：编写nacos配置中心， clouddb6.tuser
话不多说！开始体验吧！！

1.2 体验

（1）创建user测试服务
•修改父项目，添加依赖（锁定）

<?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.czxy.changgou4</groupId><artifactId>changgou4-parent-ali</artifactId><packaging>pom</packaging><version>1.0-SNAPSHOT</version><modules><module>test-nacos-cloud-provider</module><module>test-nacos-cloud-consumer</module><module>test-nacos-cloud-config</module><module>test-nacos-cloud-config-mysql-java34</module></modules><!-- 1 确定spring boot的版本--><parent><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-parent</artifactId><version>2.2.5.RELEASE</version></parent><!--2  确定版本--><properties><project.build.sourceEncoding>UTF-8</project.build.sourceEncoding><java.version>1.8</java.version><spring-cloud-release.version>Hoxton.SR3</spring-cloud-release.version><nacos.version>1.1.0</nacos.version><alibaba.cloud.version>2.2.1.RELEASE</alibaba.cloud.version><mysql.version>5.1.32</mysql.version><mybatis.plus.version>3.4.0</mybatis.plus.version><jwt.jjwt.version>0.9.0</jwt.jjwt.version><jwt.joda.version>2.9.7</jwt.joda.version><swagger.version>2.7.0</swagger.version></properties><!-- 3 锁定版本--><dependencyManagement><dependencies><!-- sprig cloud--><dependency><groupId>org.springframework.cloud</groupId><artifactId>spring-cloud-dependencies</artifactId><version>${spring-cloud-release.version}</version><type>pom</type><scope>import</scope></dependency><!--nacos --><dependency><groupId>com.alibaba.nacos</groupId><artifactId>nacos-client</artifactId><version>${nacos.version}</version></dependency><!--nacos cloud 发现 --><dependency><groupId>com.alibaba.cloud</groupId><artifactId>spring-cloud-starter-alibaba-nacos-discovery</artifactId><version>${alibaba.cloud.version}</version></dependency><!--nacos cloud 配置 --><dependency><groupId>com.alibaba.cloud</groupId><artifactId>spring-cloud-starter-alibaba-nacos-config</artifactId><version>${alibaba.cloud.version}</version></dependency><!-- https://mvnrepository.com/artifact/com.alibaba.cloud/spring-cloud-starter-alibaba-sentinel --><dependency><groupId>com.alibaba.cloud</groupId><artifactId>spring-cloud-starter-alibaba-sentinel</artifactId><version>${alibaba.cloud.version}</version></dependency><!-- mybatis plus--><dependency><groupId>com.baomidou</groupId><artifactId>mybatis-plus-boot-starter</artifactId><version>${mybatis.plus.version}</version></dependency><dependency><groupId>com.baomidou</groupId><artifactId>mybatis-plus-annotation</artifactId><version>${mybatis.plus.version}</version></dependency><!-- mysql驱动 --><dependency><groupId>mysql</groupId><artifactId>mysql-connector-java</artifactId><version>${mysql.version}</version></dependency><!--swagger2--><dependency><groupId>io.springfox</groupId><artifactId>springfox-swagger2</artifactId><version>${swagger.version}</version></dependency><dependency><groupId>io.springfox</groupId><artifactId>springfox-swagger-ui</artifactId><version>${swagger.version}</version></dependency></dependencies></dependencyManagement></project>

•创建user服务：test-nacos-cloud-config-mysql-java34
•修改pom添加依赖

 <dependencies><!-- web 启动器 --><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-web</artifactId></dependency><!-- nacos 配置--><dependency><groupId>com.alibaba.cloud</groupId><artifactId>spring-cloud-starter-alibaba-nacos-config</artifactId></dependency><!--swagger2--><dependency><groupId>io.springfox</groupId><artifactId>springfox-swagger2</artifactId></dependency><dependency><groupId>io.springfox</groupId><artifactId>springfox-swagger-ui</artifactId></dependency><!-- mybatis plus--><dependency><groupId>com.baomidou</groupId><artifactId>mybatis-plus-boot-starter</artifactId></dependency><!-- mysql驱动 --><dependency><groupId>mysql</groupId><artifactId>mysql-connector-java</artifactId></dependency><!--lombok , @Data 等--><dependency><groupId>org.projectlombok</groupId><artifactId>lombok</artifactId></dependency></dependencies>

•编写yml文件：bootstrap.yml

 # 服务端口号
server:port: 7777
# 服务名
spring:application:name: user-servicedatasource:driverClassName: com.mysql.jdbc.Driverurl: jdbc:mysql://127.0.0.1:3306/cloud_db5?useUnicode=true&characterEncoding=utf8  // 注意库名别写错了username: rootpassword: 1234cloud:nacos:config:server-addr: 127.0.0.1:8848     # nacos 服务地址prefix: user                   # 3.1 前缀，默认 ${spring.application.name}file-extension: yaml            # 3.2 后缀 , user.yamlgroup: DEFAULT_GROUP            # 3.3 组名#开启log4j打印SQL语句
logging:level:com:czxy:changgou4:mapper: debug# mp日志打印
mybatis-plus:configuration:log-impl: org.apache.ibatis.logging.stdout.StdOutImpl

•编写启动类

 package com.czxy.changgou4.user;import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;/*** @author 桐叔* @email liangtong@itcast.cn*/
@SpringBootApplication
public class UserServiceApplication {public static void main(String[] args) {SpringApplication.run(UserServiceApplication.class,args);}
}

•初始化数据库

 create database cloud_db5;
use cloud_db5;
CREATE TABLE t_user(id INT PRIMARY KEY AUTO_INCREMENT,username VARCHAR(50)
);create database cloud_db6;
use cloud_db6;
CREATE TABLE t_user(id INT PRIMARY KEY AUTO_INCREMENT,username VARCHAR(50)
);

•完成user添加
–拷贝配置类：swagger

–编写domain：Userpackage com.czxy.changgou4.user.domain;import com.baomidou.mybatisplus.annotation.IdType;
import com.baomidou.mybatisplus.annotation.TableId;
import com.baomidou.mybatisplus.annotation.TableName;
import lombok.Data;/*** @author 桐叔* @email liangtong@itcast.cn*/
@TableName("t_user")
@Data
public class User {@TableId(type = IdType.AUTO)private Integer id;private String username;
}

–编写mapper

–编写service
•接口

•实现类

•编写controller

（2）打包项目，并运行

•修改pom文件，添加maven插件，确定启动类

     <build><plugins><plugin><groupId>org.springframework.boot</groupId><artifactId>spring-boot-maven-plugin</artifactId><configuration><!--启动类--><mainClass>com.czxy.changgou4.user.UserServiceApplication</mainClass></configuration></plugin></plugins></build>

•点击package进行打包

•通过cmd运行程序找到jar所在位置上一层输入cmd

在cmd中输入 java -jar xxxx.jar（xxxx–>jar包名）

启动成功后打开swagger体验一把

查看一波数据库

（3） nacos配置，重新运行
•目的：切换数据库再体验一波

•重新运行jar，再测试

打开swagger添加

查看数据库

后记

欢迎体验，如果有更好玩的jar请在评论区分享，谢谢！！今天也要开心！！