Or alternatively modify the sequence and move the execution of the
resources-plugin in the prepare-package phase so that the META-INF/services is
only copied AFTER you’ve compiled your plugin class
<plugin>
<artifactId>maven-resources-plugin</artifactId>
<groupId>org.apache.maven.plugins</groupId>
<version>3.3.1</version>
<executions>
<execution>
<id>default-resources</id>
<phase>process-classes</phase>
</execution>
</executions>
</plugin>
> On 5 Nov 2025, at 10:31, Thomas Broyer <[email protected]> wrote:
>
> The problem is that Maven copies the src/main/resources/META-INF/services/
> to the target/classes first, and (more importantly) adds target/classes to
> the compile classpath, so when the compiler initializes, it will load that
> service descriptor and fail because com.example.JavacPlugin is not found:
> and indeed we're trying to compile it!
> (what puzzles me though is that I thought javac would only load plugins
> from the processor path, not the compile classpath)
>
> As a workaround, you could use Google's AutoService [1], or Kohsuke's
> metainf-services [2], to generate the service descriptor at compile-time
> using an annotation processor; that way the file shouldn't exist in the
> compile classpath when the compiler initializes (at least ErrorProne [3]
> uses AutoService and doesn't suffer from that error)
>
> Alternatively, configuring an explicitly empty processor path seems to
> works (I tried
> <compilerArgs><arg>-processorpath</arg><arg>:</arg></compilerArgs>; that
> ":" might not work on Windows though, where the path separator is different)
>
> [1] https://github.com/google/auto/tree/main/service
> [2] https://github.com/kohsuke/metainf-services
> [3] https://errorprone.info/
>
> On Wed, Nov 5, 2025 at 7:01 AM Mansour Al Akeel <[email protected]>
> wrote:
>
>> I am trying to build and package a sample JavacPlugin project into a jar
>> file. The project can be inspected here:
>>
>> https://github.com/malakeel/java-compiler-plugin-example
>>
>>
>> The error I am getting:
>>
>> [DEBUG] incrementalBuildHelper#beforeRebuildExecution
>> [INFO] Compiling 2 source files with javac [debug verbose target 21] to
>> target/classes
>> An exception has occurred in the compiler (21). Please file a bug against
>> the Java compiler via the Java bug reporting page (
>> https://bugreport.java.com) after checking the Bug Database (
>> https://bugs.java.com) for duplicates. Include your program, the following
>> diagnostic, and the parameters passed to the Java compiler in your report.
>> Thank you.
>> java.util.ServiceConfigurationError: com.sun.source.util.Plugin: Provider
>> com.example.JavacPlugin not found
>> at java.base/java.util.ServiceLoader.fail(ServiceLoader.java:593)
>>
>> I am using openjdk version "21"
>>
>> While I understand the problem in general, I am unable to find the exact
>> cause.
>>
>> Why is the compiler plugin unable to locate the given class, and what
>> options do I need to set to make this work ?
>> Thank you in advance.
>>
>
>
> --
> Thomas Broyer
> /tɔ.ma.bʁwa.je/
> <https://ipa-reader.com/?text=t%C9%94.ma.b%CA%81wa.je&voice=Mathieu>
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