SpringCloud入门案例

✨ SpringCloud入门案例

• 创建父工程
• • 删除src目录
  • 然后把maven改成自己的本地仓库
  • 字符编码
  • 注解生效激活
  • Java编译版本1.8
  • pom依赖
• 微服务架构编码构建-Rest微服务-【服务提供者】
• • 创建子模块
  • pom依赖
  • yml
  • 主启动类
  • 数据库
  • 实体类
  • Controller
  • Service
  • Service的实现类
  • Mapper
  • Mapper映射文件
  • 测试
• 微服务架构编码构建-Rest微服务-【服务消费者】
• • 新建模块
  • 导入依赖
  • yml
  • 主启动类
  • 创建entities
  • RestTemplate
  • 配置类
  • controller
  • 测试
• 代码改善
• • 存在的问题
  • 新建：cloud-api-commons
  • pom依赖
  • 把公共代码写在这个模块中，然后删除上面那两个模块的重复代码
  • 然后把cloud-api-commons模块的坐标添加到消费者和提供者的pom文件中
  • 测试

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🔥个人专栏:微服务专栏

创建父工程

删除src目录

然后把maven改成自己的本地仓库

字符编码

注解生效激活

Java编译版本1.8

pom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>4.0.0modelVersion>

    <groupId>com.zyh.springcloudgroupId>
    <artifactId>cloud2022artifactId>
    <version>1.0-SNAPSHOTversion>
    <packaging>pompackaging>

    
    <properties>
        <project.build.sourceEncoding>UTF-8project.build.sourceEncoding>
        <maven.compiler.source>1.8maven.compiler.source>
        <maven.compiler.target>1.8maven.compiler.target>
        <junit.version>4.12junit.version>
        <log4j.version>1.2.17log4j.version>
        <lombok.version>1.16.18lombok.version>
        <mysql.version>8.0.26mysql.version>
        <druid.version>1.1.16druid.version>
        <mybatis.spring.boot.version>1.3.0mybatis.spring.boot.version>
    properties>

    
    <dependencyManagement>
        <dependencies>
            
            <dependency>
                <groupId>org.springframework.bootgroupId>
                <artifactId>spring-boot-dependenciesartifactId>
                <version>2.2.2.RELEASEversion>
                <type>pomtype>
                <scope>importscope>
            dependency>
            
            <dependency>
                <groupId>org.springframework.cloudgroupId>
                <artifactId>spring-cloud-dependenciesartifactId>
                <version>Hoxton.SR1version>
                <type>pomtype>
                <scope>importscope>
            dependency>
            
            <dependency>
                <groupId>com.alibaba.cloudgroupId>
                <artifactId>spring-cloud-alibaba-dependenciesartifactId>
                <version>2.1.0.RELEASEversion>
                <type>pomtype>
                <scope>importscope>
            dependency>

            <dependency>
                <groupId>mysqlgroupId>
                <artifactId>mysql-connector-javaartifactId>
                <version>${mysql.version}version>
            dependency>
            <dependency>
                <groupId>com.alibabagroupId>
                <artifactId>druidartifactId>
                <version>${druid.version}version>
            dependency>
            <dependency>
                <groupId>org.mybatis.spring.bootgroupId>
                <artifactId>mybatis-spring-boot-starterartifactId>
                <version>${mybatis.spring.boot.version}version>
            dependency>
            <dependency>
                <groupId>junitgroupId>
                <artifactId>junitartifactId>
                <version>${junit.version}version>
            dependency>
            <dependency>
                <groupId>log4jgroupId>
                <artifactId>log4jartifactId>
                <version>${log4j.version}version>
            dependency>
            <dependency>
                <groupId>org.projectlombokgroupId>
                <artifactId>lombokartifactId>
                <version>${lombok.version}version>
                <optional>trueoptional>
            dependency>
        dependencies>
    dependencyManagement>

    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.bootgroupId>
                <artifactId>spring-boot-maven-pluginartifactId>
                <configuration>
                    <fork>truefork>
                    <addResources>trueaddResources>
                configuration>
            plugin>
        plugins>
    build>


project>
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微服务架构编码构建-Rest微服务-【服务提供者】

创建子模块

pom依赖

 <dependencies>
        <dependency>
            <groupId>org.springframework.bootgroupId>
            <artifactId>spring-boot-starter-webartifactId>
        dependency>
        <dependency>
            <groupId>org.springframework.bootgroupId>
            <artifactId>spring-boot-starter-actuatorartifactId>
        dependency>
        <dependency>
            <groupId>org.mybatis.spring.bootgroupId>
            <artifactId>mybatis-spring-boot-starterartifactId>
        dependency>
        <dependency>
            <groupId>com.alibabagroupId>
            <artifactId>druid-spring-boot-starterartifactId>
            <version>1.1.10version>
        dependency>
        <dependency>
            <groupId>mysqlgroupId>
            <artifactId>mysql-connector-javaartifactId>
        dependency>
        <dependency>
            <groupId>org.springframework.bootgroupId>
            <artifactId>spring-boot-starter-jdbcartifactId>
        dependency>
        <dependency>
            <groupId>org.springframework.bootgroupId>
            <artifactId>spring-boot-devtoolsartifactId>
            <scope>runtimescope>
            <optional>trueoptional>
        dependency>
        <dependency>
            <groupId>org.projectlombokgroupId>
            <artifactId>lombokartifactId>
            <optional>trueoptional>
        dependency>
        <dependency>
            <groupId>org.springframework.bootgroupId>
            <artifactId>spring-boot-starter-testartifactId>
            <scope>testscope>
        dependency>

    dependencies>
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yml

server:
  port: 8001

spring:
  application:
    name: cloud-payment-service
  datasource:
    type: com.alibaba.druid.pool.DruidDataSource
    driver-class-name: com.mysql.cj.jdbc.Driver
    url: jdbc:mysql://localhost:3306/cloud2022?serverTimezone=Asia/Shanghai&useSSL=true&useUnicode=true&characterEncoding=UTF-8
    username: root
    password: 123456

mybatis:
  mapperLocations: classpath:/mapper/*.xml
  type-aliases-package: com.zyh.springcloud.entities
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主启动类

数据库

CREATE DATABASE  IF NOT EXISTS cloud2022 DEFAULT CHARACTER SET utf8 ;

USE cloud2022 ;

DROP TABLE IF EXISTS payment ;

CREATE TABLE payment (
  id BIGINT (20) NOT NULL AUTO_INCREMENT COMMENT 'ID',
  SERIAL VARCHAR (300) DEFAULT NULL,
  PRIMARY KEY (id)
) ENGINE = INNODB AUTO_INCREMENT = 33 DEFAULT CHARSET = utf8 ;

INSERT INTO payment (id, SERIAL) VALUES(1, '皮卡丘1'),(2, '皮卡丘2') ;

 

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实体类

Controller

com.zyh.springcloud.controller.PaymentController

@RestController
@Slf4j
public class PaymentController {

    @Autowired
    private PaymentService paymentService;

    @PostMapping(value = "/payment/create")
    public CommonResult<Payment> create(@RequestBody Payment payment){
        int result = paymentService.create(payment);
        log.info("*****插入结果："+payment);
        if (result>0){  //成功
            return new CommonResult(200,"插入数据库成功",payment);
        }else {
            return new CommonResult(444,"插入数据库失败",null);
        }
    }

    @GetMapping(value = "/payment/get/{id}")
    public CommonResult<Payment> getPaymentById(@PathVariable("id") Long id){
        Payment payment = paymentService.getPaymentById(id);
        log.info("*****查询结果："+payment);
        if (payment!=null){  //说明有数据，能查询成功
            return new CommonResult(200,"查询成功",payment);
        }else {
            return new CommonResult(444,"没有对应记录，查询ID："+id,null);
        }
    }
}
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Service

com/zyh/springcloud/service/PaymentService.java

public interface PaymentService {
    /**
     * 存储数据
     * @param payment
     * @return
     */
     int create(Payment payment);

    /**
     * 获取数据
     * @param id
     * @return
     */
      Payment getPaymentById(Long id);
}
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Service的实现类

com/zyh/springcloud/service/impl/PaymentServiceImpl.java

@Service
public class PaymentServiceImpl implements PaymentService {
    @Autowired
    private PaymentMapper paymentMapper;
    @Override
    public int create(Payment payment) {
        return paymentMapper.create(payment);
    }

    @Override
    public Payment getPaymentById(Long id) {
        return paymentMapper.getPaymentById(id);
    }
}

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Mapper

com/zyh/springcloud/mapper/PaymentMapper.java

@Mapper
public interface PaymentMapper {
    /**
     * 插入一条数据
     * @param payment
     * @return
     */
    int create(Payment payment);

    /**
     * 根据id查询数据
     * @param id
     * @return
     */
    Payment getPaymentById(@Param("id") long id);
}

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Mapper映射文件

DOCTYPE mapper
        PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
        "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="com.zyh.springcloud.mapper.PaymentMapper">
    <insert id="create"  useGeneratedKeys="true" keyProperty="id">
        insert into payment(serial) values(#{serial});
    insert>

    <resultMap id="BaseResultMap" type="com.zyh.springcloud.entities.Payment">
        <id column="id" property="id" jdbcType="BIGINT">id>
        <result column="serial" property="serial" jdbcType="VARCHAR">result>
    resultMap>

    <select id="getPaymentById"  parameterType="Long" resultMap="BaseResultMap">
        select * from payment where id=#{id}
    select>
mapper>
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测试

微服务架构编码构建-Rest微服务-【服务消费者】

新建模块

导入依赖

<dependencies>
        <dependency>
            <groupId>org.springframework.bootgroupId>
            <artifactId>spring-boot-starter-webartifactId>
        dependency>
        <dependency>
            <groupId>org.springframework.bootgroupId>
            <artifactId>spring-boot-starter-actuatorartifactId>
        dependency>
        <dependency>
            <groupId>org.springframework.bootgroupId>
            <artifactId>spring-boot-devtoolsartifactId>
            <scope>runtimescope>
            <optional>trueoptional>
        dependency>
        <dependency>
            <groupId>org.projectlombokgroupId>
            <artifactId>lombokartifactId>
            <optional>trueoptional>
        dependency>
        <dependency>
            <groupId>org.springframework.bootgroupId>
            <artifactId>spring-boot-starter-testartifactId>
            <scope>testscope>
        dependency>
    dependencies>
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yml

server:
  port: 80
spring:
  application:
    name: cloud-consumer-order80
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主启动类

创建entities

(将cloud-provider-payment8001工程下的entities包下的两个实体类复制过来)

RestTemplate

• RestTemplate提供了多种便捷访问远程Http服务的方法，是一种简单便捷的访问Restful服务模板类，是Spring 提供的用于访问Rest服务的客户端模板工具集。
• Spring框架提供的RestTemplate类可用于在应用中调用rest服务，它简化了与http服务的通信方式，统

一了RESTful的标准，封装了http链接， 我们只需要传入url及返回值类型即可。相较于之前常用的HttpClient，RestTemplate是一种更优雅的调用RESTful服务的方式。

• 在Spring应用程序中访问第三方REST服务与使用Spring RestTemplate类有关。RestTemplate类的设计

原则与许多其他Spring 模板类(例如JdbcTemplate、JmsTemplate)相同，为执行复杂任务提供了一种具
有默认行为的简化方法。

• RestTemplate默认依赖JDK提供http连接的能力（HttpURLConnection），如果有需要的话也可以通过

setRequestFactory方法替换为例如 Apache HttpComponents、Netty或OkHttp等其它HTTP library。
考虑到RestTemplate类是为调用REST服务而设计的，因此它的主要方法与REST的基础紧密相连就不足
为奇了，后者是HTTP协议的方法:HEAD、GET、POST、PUT、DELETE和OPTIONS。例如， RestTemplate类具有headForHeaders()、getForObject()、postForObject()、put()和delete()等方法。

• 官网及使用
• 官网地址：https://docs.spring.io/spring-framework/docs/5.2.2.RELEASE/javadoc-api/org/springframework/web/client/RestTemplate.html
• 使用RestTemplate访问Restful接口非常的简单粗暴无脑。（url，requestMap，ResponseBean.class）这三个参数分别代表REST请求地址、请求参数、Http响应转换被转换成的对象类型。

配置类

把service拷贝过来

controller

@RestController
@Slf4j
public class OrderController {
    /*面向接口编程：推荐，但是需要使用OpenFeign组件
    @Autowired
    private PaymentService paymentService;

    @RequestMapping("/consumer/payment/get/{id}")
    public CommonResult get(@PathVariable("id")Long id){
        Payment payment = paymentService.getPaymentById(id);
        System.out.println("payment:"+payment);
        return new CommonResult(200,"操作成功",payment);

    }

    @PostMapping("/consumer/payment/create")
    public CommonResult create(@RequestBody Payment payment){
        System.out.println("payment:"+payment);
        paymentService.create(payment);
        return new CommonResult(200,"操作成功",payment);
    }
    */

    /**
     * 基于RestTemplate模板类进行远程调用
     */
    public static final String PAYMENT_URL = "http://localhost:8001";

    @Autowired
    private RestTemplate restTemplate;

    @RequestMapping("/consumer/payment/get/{id}")
    public CommonResult get(@PathVariable("id") Long id) {
        CommonResult<Payment> commonResult = restTemplate.getForObject(PAYMENT_URL + "/payment/get/" + id, CommonResult.class);
        log.info("commonResult:" + commonResult);
        return commonResult;
    }

    @PostMapping("/consumer/payment/create")
    public CommonResult create(@RequestBody Payment payment) {
        log.info("payment:"+payment);
        CommonResult commonResult = restTemplate.postForObject(PAYMENT_URL + "/payment/create", payment, CommonResult.class);
        return commonResult;
    }

}

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测试

1. 先启动cloud-provider-payment8001
   
2. 再启动cloud-consumer-order80
   
3. http://localhost/consumer/payment/get/1
   
4. 不要忘记@RequestBody注解
   
5. 服务提供者接口方法需要增加@RequestBody注解；否则，接收不到数据。
   
   
   
   
   

代码改善

存在的问题

上面所写的模块，存在以下问题，两个模块都用到了实体类，但是代码是重复的，我们可以提取出来。

新建：cloud-api-commons

pom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">
    <parent>
        <artifactId>cloud2022artifactId>
        <groupId>com.zyh.springcloudgroupId>
        <version>1.0-SNAPSHOTversion>
    parent>
    <modelVersion>4.0.0modelVersion>

    <groupId>com.zyh.springcloudgroupId>
    <version>1.0-SNAPSHOTversion>
    <artifactId>cloud-api-commonsartifactId>
    
    <properties>
        <maven.compiler.source>8maven.compiler.source>
        <maven.compiler.target>8maven.compiler.target>
    properties>
    <dependencies>
        <dependency>
            <groupId>org.springframework.bootgroupId>
            <artifactId>spring-boot-devtoolsartifactId>
            <scope>runtimescope>
            <optional>trueoptional>
        dependency>

        <dependency>
            <groupId>org.projectlombokgroupId>
            <artifactId>lombokartifactId>
            <optional>trueoptional>
        dependency>
        <dependency>
            <groupId>cn.hutoolgroupId>
            <artifactId>hutool-allartifactId>
            <version>5.1.0version>
        dependency>
    dependencies>


project>
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把公共代码写在这个模块中，然后删除上面那两个模块的重复代码

然后把cloud-api-commons模块的坐标添加到消费者和提供者的pom文件中

<groupId>com.zyh.springcloud</groupId>
    <version>1.0-SNAPSHOT</version>
    <artifactId>cloud-api-commons</artifactId>
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测试