[FIXED] Can the submodules use the reactor as parent in Maven?

Issue

Hello Stackoverflow community,

i recently started working with maven to see what is possible or better to see if its easier to have a dependency manager or including everything to your own.

Basic Informations

Repository

href="https://github.com/JXCoding/MavenTests" rel="nofollow noreferrer">https://github.com/JXCoding/MavenTests

Reactor

<groupId>de.jxson.maven</groupId>
<artifactId>MavenTests</artifactId>
<packaging>pom</packaging>
<version>1.0.0-SNAPSHOT</version>

<modules>
    <module>API</module>
    <module>v1_18_R1</module>
</modules>

submodule API

<parent>
  <artifactId>MavenTests</artifactId>
  <groupId>de.jxson.maven</groupId>
  <version>1.0.0-SNAPSHOT</version>
</parent>

<artifactId>API</artifactId>

<dependencies>
...
</dependencies>

Which depends of reactor as parent

submodule v1_18_R1

<parent>
    <artifactId>MavenTests</artifactId>
    <groupId>de.jxson.maven</groupId>
    <version>1.0.0-SNAPSHOT</version>
</parent>
<artifactId>v1_18_R1</artifactId>

<dependencies>
  <dependency>
      <groupId>de.jxson.maven</groupId>
      <artifactId>API</artifactId>
      <version>1.0.0-SNAPSHOT</version>
      <scope>compile</scope>
  </dependency>
</dependencies>

Which depends of API and reactor as parent

My Problem is:

When I build with mvn clean package, there is an error on my module v1_18_R1 in which a class from API is not found.

Questions:

Why a class is not found if the required dependency is already added?

Solution

Usually maven reactor is used for:

• Collects all the available modules to build
• Sorts the projects into the correct build order
• Builds the selected projects in order

And not to be as parent of another projects. If you need to centralize libraries , versions, etc create a extra project with <packaging>pom</packaging>.

Solution

• Remove the parent from your submodules
• Add this to all of your submodules which requires spigot jars

<repositories>
    <repository>
      <id>elmakers-repo</id>
      <url>https://maven.elmakers.com/repository/</url>
    </repository>
</repositories>

WIth these fixes, I was able to build your git repository with mvn clean package

Spigot notes

• offical git repository don't build https://hub.spigotmc.org/stash/projects/SPIGOT
• Official repository don't works: https://www.spigotmc.org/wiki/spigot-maven/
• Only this repository works https://maven.elmakers.com/repository/org/spigotmc/spigot/

Answered By - JRichardsz
Answer Checked By - Cary Denson (JavaFixing Admin)