os.detected.classifier not set - os-maven-plugin and eclipse oxygen

Question

I'm suffering the maven-protoc-plugin issue where os.detected.classifier isn't resolved causing eclipse to report an error in my pom.

I found this fix but I suspect that only works for older eclipse versions, there is no longer a <eclipse>/plugins folder in oxygen.

I've tried setting os.detected.classifier in eclipse.ini and windows environment variables to no avail.

Here's a clip of the pom for those that think it will help..

<build>
    <extensions>
        <extension>
            <groupId>kr.motd.maven</groupId>
            <artifactId>os-maven-plugin</artifactId>
            <version>1.3.0.Final</version>
        </extension>
    </extensions>             
    <plugins>
         <plugin>
            <groupId>com.google.protobuf.tools</groupId>
            <artifactId>maven-protoc-plugin</artifactId>
            <version>0.4.3</version>
            <executions>
                <execution>
                    <goals>
                        <goal>compile</goal>

And part of the error...

Missing:
----------
1) com.google.protobuf:protoc:exe:${os.detected.classifier}:2.6.1

Try downloading the file manually from the project website.

Answer 1

In case it does not work for you instead of using the "extension" syntax you can register it as a plugin:

    <plugin>
      <groupId>kr.motd.maven</groupId>
      <artifactId>os-maven-plugin</artifactId>
      <version>1.6.2</version>
      <executions>
        <execution>
          <phase>initialize</phase>
          <goals>
            <goal>detect</goal>
          </goals>
        </execution>
      </executions>
    </plugin>

Answer 2

I know it is an old question, but I just ran into the same problem and found a solution that works for me.

Eclipse m2e does not process the maven os plugin/extension properly. There are a few suggestions available.

The one that worked for me with least effort was to add the plugin jar to the Eclipse dropins directory. On my mac is it is

~/eclipse/java-2018-12/Eclipse.app/Contents/Eclipse/dropins

The file is located on the maven repo here

Copy the file there, restart eclipse clean, and the os.detected.classifier will be properly expanded in m2e on eclipse.

Answer 3

Add the following extension to your pom file: `

<project>
  <build>
    <extensions>
      <extension>
        <groupId>kr.motd.maven</groupId>
        <artifactId>os-maven-plugin</artifactId>
        <version>1.6.1</version>
      </extension>
    </extensions>
  </build>
</project>

`