Java 11 added the new writeBytes method to ByteArrayOutputStream that clashes with the pre-existing one. This can be fixed just by adjusting to the parent signature as well as other methods to not throw Exceptions. The impact should be minimal because this is a package private class.
[ERROR] Failed to execute goal org.apache.maven.plugins:maven-compiler-plugin:3.8.0:compile (default-compile) on project trevni-core: Compilation failure
[ERROR] /home/ismael/workspace/avro05/lang/java/trevni/core/src/main/java/org/apache/trevni/OutputBuffer.java:[102,15] writeBytes(byte) in org.apache.trevni.OutputBuffer cannot override writeBytes(byte) in java.io.ByteArrayOutputStream
[ERROR] overridden method does not throw java.io.IOException