scope import resolution in pom.xml

use:

        Using scope import can solve Maven 's single inheritance problem.

explain:

        Maven itself supports inheritance. Many times we will create multi-module projects, and multiple modules will introduce the same dependencies. At this time, we can use Maven 's parent-child project structure. Create a parent pom.xml . The pom.xml files in other projects inherit the parent pom.xml . The content of the pom.xml of the submodule is shown in the following figure:

<parent>
    <groupId>com</groupId>
	<artifactId>springboot_dubbo</artifactId>
	<version>0.0.1-SNAPSHOT</version>
</parent>

        Through the above method, we can make our dependency management more regulated. However, the Maven parent-child project structure is the same as Java inheritance, which is single inheritance . A sub-project can only formulate one parent pom . In many cases, we need to break this single inheritance.

        For example, when using spring-boot , the official recommended way is to inherit the parent pom , as shown in the following figure:

<parent>
    <groupId>org.springframework.boot</groupId>
	<artifactId>spring-boot-starter-parent</artifactId>
	<version>2.1.4.RELEASE</version>
</parent>

        But what if you already have other parent pom in the project and want to use spring-boot ? At this time, you need to use scope import and specify type pom , as shown in the following figure:

<dependencyManagement>
    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-parent</artifactId>
            <version>2.1.4.RELEASE</version>
            <scope>import</scope>
            <type>pom</type>
        </dependency>
    </dependencies>
</dependencyManagement>

        Note: scope import can only be used in <dependencyManagement> modules .