Spring Boot-maven依赖：spring-boot-starter-parent

Springboot-maven依赖：spring-boot-starter-parent

这是Springboot父级依赖，表示当前是Springboot项目

可以用来控制Maven默认依赖版本，使用后可以省去version标签。spring-boot-starter-web和`spring-

未使用spring-boot-starter-parent

<dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
            <version>2.4.2</version>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <version>2.4.2</version>
        </dependency>
</dependencies>

boot-starter-test`的版本都是2.4.2

省去写version了

使用spring-boot-starter-parent

<parent>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-parent</artifactId>
    <version>2.4.2</version>
    <relativePath/>
</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>
        </dependency>
</dependencies>