Maven duplicate class with generated sources when using -f option - maven

Question

I try to build a Maven project with classes generated from jaxb2-maven-plugin.
Consider the following minimal pom.xml:
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>test</groupId>
<artifactId>test</artifactId>
<version>0.0.1-SNAPSHOT</version>
<build>
<plugins>
<plugin>
<groupId>org.codehaus.mojo</groupId>
<artifactId>jaxb2-maven-plugin</artifactId>
<version>2.3.1</version>
<executions>
<execution>
<goals>
<goal>xjc</goal>
</goals>
<configuration>
<packageName>test</packageName>
<sources>
<source>src/main/resources/schema.xsd</source>
</sources>
</configuration>
</execution>
</executions>
</plugin>
</plugins>
</build>
</project>
And this minimal schema in src/main/resources/schema.xsd:
<?xml version="1.0" encoding="UTF-8"?>
<xs:schema elementFormDefault="qualified" vc:maxVersion="1.1" vc:minVersion="1.0" xmlns:vc="http://www.w3.org/2007/XMLSchema-versioning" xmlns:xs="http://www.w3.org/2001/XMLSchema">
<xs:element name="root" type="xs:string"/>
</xs:schema>
When invoking mvn clean compile, the project is built as expected. But when I specify the file using a path containing .., the following error occurs. When using a (relative or absolute) path without .., everything is fine.
C:\dev\test>mvn -f ..\test\pom.xml clean compile
[...]
[ERROR] Failed to execute goal org.apache.maven.plugins:maven-compiler-plugin:3.1:compile (default-compile) on project test: Compilation failure: Compilation failure:
[ERROR] /C:/dev/test/target/generated-sources/jaxb/test/ObjectFactory.java:[32,8] duplicate class: test.ObjectFactory
How can I get rid of this error and build my project using mvn -f <some path containing "..">?

Answer 1

For me (on macOS), the issue goes away when I don't have a "." component in my path:
maven compile -f ./blah/blah # <-- "duplicate class" errors
maven compile -f blah/blah # <-- works fine
Ugly workaround: Try using an absolute path?
(Seems like a path normalization bug in Maven or maven-compiler-plugin.)