I'm currently trying to get a bit of practice in working with DXA 2.0 in Java. Some months ago I did SDL's DXA course, which gets you in the quickest possible way to a working DXA implementation. You have to follow up by filling in the details, and today was the first time I'd tried to create a module by actually following the instructions in the documentation. 

I was looking at the documentation page for Building a Java module with Maven POM, and my first attempt was simply to copy the POM from the documentation. Although it seemed like a good idea at the time, pretty soon I was staring at a  nasty-looking error: 

Project build error: Non-resolvable parent POM for dxa-modules:module-one:[unknown-version]: 
Could not find artifact com.sdl.dxa.modules:dxa-modules:pom:1.2-SNAPSHOT and 
'parent.relativePath' 
points at wrong local POM pom.xml /module-one line 3 Maven pom Loading Problem

When I say it seemed like a good idea at the time, to tell the truth, I'd already had my doubts when I saw SNAPSHOT, and that indeed turned out to be the problem. When using Maven, a snapshot build is one that a developer creates locally; you wouldn't expect a snapshot build to be released to a repository. Statistically speaking, Java developers spend 17.3% of their working hours Googling for the correct versions of external dependencies that they need to get out of various external repositories. That's the great thing about Maven; once you get the versions right, everything works by magic and you can go and have a cup of tea. 

So - like thousands before me, I duly Googled, and ended up on a page that told me I could use version 1.3.0. 

So I fixed up the POM so that this: 

<parent> 
 <groupId>com.sdl.dxa.modules</groupId>
 <artifactId>dxa-modules</artifactId> 
 <version>1.2-SNAPSHOT</version> 
</parent>

looked like this: 

<parent> 
 <groupId>com.sdl.dxa.modules</groupId>
 <artifactId>dxa-modules</artifactId> 
 <version>1.3.0</version>
</parent>

That's fixed it, so now I can get on with the rest of the job. And sure, this is blindingly obvious if you do a lot of Java, but these little things can slow you down a fair bit. In this case, I'd spent some time obsessing about Maven a while back, so I got there reasonably quickly, but we're not always that lucky!