There is straightforward documentation on how to push to Maven Central using maven, but I need to do it using ant and it has bit more complicated process. So my question is - can I push jar file directly to Maven Central repository, without using ant maven plugin?
If you deploy via Open Source Software Repository Hosting (OSSRH), then it is the Sonatype Nexus web interface that also has the form for manual deployment. You can upload your pom, jar and all signatures by hand if so preferred into snapshot or staging repository, then close the repository, and, if it is ok, release it, then all goes to Maven Central and becomes immutable. You still need to include all PGP signatures into your upload however.