I like maven. I've used it since pre 1.0. It's a powerful tool that on balance has saved me considerable amounts of time, and improved my development infrastructure. But I can understand the frustration some people have. I see 3 types of frustration:
- where the causes are real concerns (e.g. verbose POMs, lacking documentation),
- some is misinformation (e.g. "you have to have an internet connection to build" - not true - doin't, this can be avoided),
- some of it is vented at maven but really someone else is culpable ("don't shoot the messenger").
For the first case, real problems - well, sure, there are problems, POMs are verbose, documentation could be better. Yet despite this, it is possible to get good results with maven in quick time. I cringe every time I get a project built with ant, and try to import this into my IDE. It can take a long time to set up the directory structure. with maven, it's just a case of opening the POM file in the IDE.
For the second case, Maven is complex, and misunderstandings are commonplace. If maven 3 can find a way to address this complexity (or even perceived complexity) that would be good. maven does take a considerable investment, but, in my experience, the investment pays for itself quickly.
For the last point, I think the gripe about maven's transitive dependencies is probably the best known example.
Transitive dependencies are the nature of real software employing reuse. Windows DLLs, Debian packages, java packages, OSGi bundles, even C++ header file includes all have dependencies and suffer the dependency problem. If you have two dependences, and each uses a different version of the same thing, then you have to try to resolve that somehow. Maven doesn't try to solve the dependency problem, but rather brings it to the forefront, and provides tools to help manage the problem, such as by reporting conflicts and providing consistent dependencies for a hierarchy of projects, and in fact provides absolute control over a project's dependencies.
The approach of manually including dependencies with each project (one poster says he checks all dependencies into source control) is runing the risk of using the wrong dependency, such as overlooked updates when a library is updated without checking in updates for it's dependencies. For a project of any size, managing dependencies manually is surely going to lead to errors. With maven, you can update the library version you use and the correct dependencies are included. For change management, you can compare the old set of dependencies (for your project as a whole) with the new set, and any changes can be carefully scrutinized, tested etc.
Maven isn't the cause of the dependency problem, but makes it more visible. In tackling dependency issues, maven makes any dependency "tweaks" explicit (a change to your POM overriding the dependency), rather than implicit, as is the case with manually managed jars in version control, where the jars are simply present, with nothing to support weather they are the correct dependency or not.
