Can't build straight out of github

[maydings]

Followed the instructions to git clone and mvnw package straight up to ubuntu 18:

This is the error I get from maven:
Downloaded from central: https://repo.maven.apache.org/maven2/log4j/log4j/1.2.17/log4j-1.2.17.jar (490 kB at 37 kB/s)
Downloaded from central: https://repo.maven.apache.org/maven2/net/sf/docbook/docbook-xsl/1.79.1/docbook-xsl-1.79.1-ns-resources.zip (4.4 MB at 323 kB/s)
[INFO] Processing input file: manual.xml
[INFO] Applying customization parameters after docbkx parameters
Error
Failure reading /home/ubuntu/sqlline/src/docbkx/manual.xml: sun.security.validator.ValidatorException: PKIX path building failed: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target
[INFO] ------------------------------------------------------------------------
[INFO] BUILD FAILURE
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 48.593 s
[INFO] Finished at: 2021-03-04T20:52:53-05:00
[INFO] ------------------------------------------------------------------------
[ERROR] Failed to execute goal com.agilejava.docbkx:docbkx-maven-plugin:2.0.17:generate-html (default) on project sqlline: Failed to transform manual.xml.: Failure reading /home/ubuntu/sqlline/src/docbkx/manual.xml: sun.security.validator.ValidatorException: PKIX path building failed: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target -> [Help 1]
[ERROR]
[ERROR] To see the full stack trace of the errors, re-run Maven with the -e switch.
[ERROR] Re-run Maven using the -X switch to enable full debug logging.
[ERROR]
[ERROR] For more information about the errors and possible solutions, please read the following articles:
[ERROR] [Help 1] http://cwiki.apache.org/confluence/display/MAVEN/MojoExecutionException

[julianhyde]

Are you using JDK 15?

[maydings]

I am using JDK 8.
I had to edit the pom file and set skip.docbkx to true to get it to build, which it successfully did afterwards.

[julianhyde]

The build works for me under JDK 8.

Maybe you are running into ARTIFACTORY: How to Resolve an “unable to find valid certification path to requested target” Error. Can you try the steps suggested there?