If you need to generate a txt with project version / timestamp in project’s root you can use an ant build like this.
<plugins> ... <plugin> <artifactId>maven-antrun-plugin</artifactId> <version>1.8</version> <executions> <execution> <phase>prepare-package</phase> <configuration> <tasks> <tstamp> <format property="now" pattern="yyyy-MM-dd hh:mm:ss" locale="it" /> </tstamp> <echo file="<path>/version.txt" append="false"> Project Version : ${project.version} ${line.separator}Build @ ${now} </echo> </tasks> </configuration> <goals> <goal>run</goal> </goals> </execution> </executions> </plugin> ... </plugins>