开发环境

• Windows 10
• Oracle JDK 1.8
• Maven 3.8.8
• IntelliJ IDEA 2022.2.2

问题

在使用 Spring initializr 创建 Spring Boot 项目时，无法引入 mysql-connector-j 这个依赖，报错信息：

com.mysql:mysql-connector-j:jar:unknown was not found in https://maven.aliyun.com/repository/public during a previous attempt. This failure was cached in the local repository and resolution is not reattempted until the update interval of aliyunmaven has elapsed or updates are forced

pom.xml 文件

// 父依赖
<parent><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-parent</artifactId><version>2.5.14</version><relativePath/> <!-- lookup parent from repository -->
</parent><dependencies><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>com.mysql</groupId><artifactId>mysql-connector-j</artifactId><version>8.0.32</version><scope>runtime</scope></dependency><dependency><groupId>com.baomidou</groupId><artifactId>mybatis-plus-boot-starter</artifactId><version>3.5.3.1</version></dependency>
</dependencies>

原因

我使用的 Spring Boot 版本为 2.5.14，该版本使用的 mysql-connector-j 版本为 8.0.29，同时我的依赖是从阿里云的镜像库而不是 Maven 的中央仓库上下载的。我尝试手动引入这个版本。

<dependency><groupId>com.mysql</groupId><artifactId>mysql-connector-j</artifactId><version>8.0.29</version><scope>runtime</scope>
</dependency>

结果报了同样的错误。也就是说，阿里云镜像仓库可能没有这个版本的 mysql-connector-j。

解决方法

手动引入高于 8.0.29 版本的 mysql-connector-j 即可解决。

<dependency><groupId>com.mysql</groupId><artifactId>mysql-connector-j</artifactId><version>8.0.32</version><scope>runtime</scope>
</dependency>