SpringCloudSpringCloud 简单的 Demo

Posted 2022-12-09 张学徒

IDEA 2022
jdk 1.8
所学的链接：springCloud — 初级篇(1) 内容更多

SpringCloud 版本问题

写 SpringCloud 项目一定要注意版本问题，一定要和 SpringBoot 的版本对应，否则 SpringCloud 启动失败

进入 https://spring.io/projects/spring-cloud/ 向下滚动查看对应 SpringCloud 版本支持的 SpringBoot 版本。

如下图 2021.0.x aka Jubilee 系列版本仅支持 SpringBoot 2.6.x 版本

学习方式

在这个教程下面的内容，除了在创建模块、application.yml 文件（配置）和 Application 启动类（注解）的部分需要多多注意以外，其他部分和正常的 SpringBoot 开发都没什么两样，其他的复制粘贴进行查看效果即可。

开始

直接开始写项目

需要先创建一个数据库 cloudtest

create database cloudtest;
use cloudtest;

create table payment(
    `id` bigint(20) primary key auto_increment,
    `serial` varchar(200)
)character set utf8;

insert into payment
values (1, 'zhangsan'),
	(2, 'lisi'),
	(3, 'wangwu');

创建 SpringCloudDemo 项目

创建一个 Maven 项目，选中 Maven 直接点击下一步

项目名 SpringCloudDemo

点击 finish 进行创建

点击 pom.xml 文件，追加以下依赖包（这个是添加的内容，不要把原本的删除了）

    <!-- 表示该工程是一个父工程 -->
    <packaging>pom</packaging>

    <!--统一管理jar包版本 -->
    <properties>
        <maven.compiler.source>8</maven.compiler.source>
        <maven.compiler.target>8</maven.compiler.target>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>

        <spring-boot.version>2.2.2.RELEASE</spring-boot.version>
        <spring-cloud.version>Hoxton.SR3</spring-cloud.version>
        <spring-cloud.alibaba.version>2.2.5.RELEASE</spring-cloud.alibaba.version>

        <junit.version>4.12</junit.version>
        <lombok.version>1.18.10</lombok.version>
        <log4j.version>1.2.17</log4j.version>
        <mysql.version>8.0.22</mysql.version>

        <mybatis.spring.boot.version>1.3.2</mybatis.spring.boot.version>
    </properties>

    <!--子模块继承之后，提供作用：锁定版本+子module不用写groupId和version -->
    <!-- 只是声明依赖，不会引入具体依赖 -->
    <dependencyManagement><!--定义规范，但不导入 -->
        <dependencies>

            <!--spring boot -->
            <dependency>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-dependencies</artifactId>
                <version>$spring-boot.version</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>

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

            <!--spring cloud 阿里巴巴 -->
            <dependency>
                <groupId>com.alibaba.cloud</groupId>
                <artifactId>spring-cloud-alibaba-dependencies</artifactId>
                <version>$spring-cloud.alibaba.version</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>

            <!-- mysql -->
            <dependency>
                <groupId>mysql</groupId>
                <artifactId>mysql-connector-java</artifactId>
                <version>$mysql.version</version>
                <scope>runtime</scope>
            </dependency>

            <!--mybatis -->
            <dependency>
                <groupId>org.mybatis.spring.boot</groupId>
                <artifactId>mybatis-spring-boot-starter</artifactId>
                <version>$mybatis.spring.boot.version</version>
            </dependency>

            <!--junit -->
            <dependency>
                <groupId>junit</groupId>
                <artifactId>junit</artifactId>
                <version>$junit.version</version>
            </dependency>

        </dependencies>
    </dependencyManagement>

    <!--热启动插件 -->
    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
                <configuration>
                    <fork>true</fork>
                    <addResources>true</addResources>
                </configuration>
            </plugin>
        </plugins>
    </build>

有时上方的依赖有个别不能下载，这时候就要到 https://mvnrepository.com/ 去搜索对应的 artifactId 名字去看看是否还能下载了，可能这个依赖有漏洞不能下载…比如阿里巴巴的 Druid 包（如下图）。那就得再找找看看能不能用，或改其他方法了，多百度看看…

默认创建的 src 文件夹可以直接删除了，当前示例用不到

添加一个模块，右键选中项目文件夹 – New – Module…，选中 Maven，点击下一步，

创建cloud-api-commons模块

存放一些公共功能的类

pom 文件中追加依赖

    <properties>
        <maven.compiler.source>8</maven.compiler.source>
        <maven.compiler.target>8</maven.compiler.target>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
    </properties>

    <dependencies>

        <!-- DevTools -->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-devtools</artifactId>
            <scope>runtime</scope>
            <optional>true</optional>
        </dependency>

        <!-- Lombok -->
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <optional>true</optional>
        </dependency>

        <!-- 糊涂工具包 -->
        <dependency>
            <groupId>cn.hutool</groupId>
            <artifactId>hutool-all</artifactId>
            <version>5.3.9</version>
        </dependency>
    </dependencies>

创建实体类 Payment

package com.zcq.springcloud.entity;

import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;

import java.io.Serializable;

/**
 * @author z
 */
@Data
@NoArgsConstructor
@AllArgsConstructor
public class Payment implements Serializable 

    private Long id;
    private String serial;

创建一个 JSON 数据实体类，用于返回响应的数据

package com.zcq.springcloud.util;

import lombok.Data;

@Data
public class JsonResult<T> 
    private Integer code;
    private String message;
    private T data;

    public JsonResult(Integer code, String message) 
        this(code, message, null);
    

    public JsonResult(Integer code, String message, T data) 
        super();
        this.code = code;
        this.message = message;
        this.data = data;
    

    public JsonResult() 
        super();
    

目录结构如下

创建 cloud-provider-payment8001 模块

创建模块步骤和上面创建 cloud-api-commons 模块的步骤一样，这个模块名设为 cloud-provider-payment8001，这个模块充当支付服务

pom 依赖

    <properties>
        <maven.compiler.source>8</maven.compiler.source>
        <maven.compiler.target>8</maven.compiler.target>
    </properties>


    <dependencies>

        <!--另一个模块-->
        <dependency>
            <groupId>org.example</groupId>
            <artifactId>cloud-api-commons</artifactId>
            <version>1.0-SNAPSHOT</version>
        </dependency>


        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-actuator </artifactId>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-jdbc</artifactId>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-devtools</artifactId>
            <scope>runtime</scope>
            <optional>true</optional>
        </dependency>

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

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-autoconfigure</artifactId>
        </dependency>

		
        <dependency>
            <groupId>org.mybatis.spring.boot</groupId>
            <artifactId>mybatis-spring-boot-starter</artifactId>
        </dependency>

        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
        </dependency>


        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <optional>true</optional>
        </dependency>

    </dependencies>

Dao 层的 Mapper

package com.zcq.springcloud.mapper;

import com.zcq.springcloud.entity.Payment;
import org.apache.ibatis.annotations.Mapper;
import org.apache.ibatis.annotations.Param;

@Mapper
public interface PaymentDao 

    int create(Payment payment);

    Payment getPaymentById(@Param(("id")) Long id);

Service 层

PaymentService

package com.zcq.springcloud.service;

import com.zcq.springcloud.entity.Payment;
import org.apache.ibatis.annotations.Param;

public interface PaymentService 

    int create(Payment payment);

    Payment getPaymentById(@Param(("id")) Long id);

PaymentServiceImpl

package com.zcq.springcloud.service.impl;

import com.zcq.springcloud.entity.Payment;
import com.zcq.springcloud.mapper.PaymentDao;
import com.zcq.springcloud.service.PaymentService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

@Service
public class PaymentServiceImpl implements PaymentService 

    @Autowired
    private PaymentDao paymentDao;

    @Override
    public int create(Payment payment) 
        return paymentDao.create(payment);
    

    @Override
    public Payment getPaymentById(Long id) 
        return paymentDao.getPaymentById(id);
    

Controller 层

package com.zcq.springcloud.controller;

import com.zcq.springcloud.entity.Payment;
import com.zcq.springcloud.service.PaymentService;
import com.zcq.springcloud.util.JsonResult;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.*;

@RestController
@RequestMapping("/payment")
@Slf4j
public class PaymentController 

    @Autowired
    private PaymentService paymentService;

    @PostMapping("/create")
    public JsonResult<Payment> create(@RequestBody Payment payment) 
        final int result = paymentService.create(payment);
        log.info("-- 插入结果：" + result);
        if (result > 0) 
            return new JsonResult<>(200, "success", null);
         else 
            return new JsonResult<>以上是关于SpringCloudSpringCloud 简单的 Demo的主要内容，如果未能解决你的问题，请参考以下文章
 
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