Comments on: Maven, Spring, Vaadin and Google AppEngine, Happy Together

By: server encountered an internal error () - Forum - vaadin.com

server encountered an internal error () - Forum - vaadin.com — Fri, 17 Jun 2011 12:17:14 +0000

[...] Then I enable dependecy management (Maven) on that project and it breaks.My pom.xml downloaded from Maven, Spring, Vaadin and Google AppEngine, Happy Together 1http://maven.apache.org/POM/4.0.0" [...]

By: Vuosi lähestyy loppuaan – Scalaa ja App Engineä ;) « Spagettikoodi

Vuosi lähestyy loppuaan – Scalaa ja App Engineä ;) « Spagettikoodi — Fri, 31 Dec 2010 13:00:04 +0000

[...] http://www.streamhead.com/maven-spring-vaadin-appengine/ [...]

By: Launching my First Vaadin AppEngine Project

Launching my First Vaadin AppEngine Project — Fri, 03 Sep 2010 08:05:05 +0000

[...] Integrating Maven, Spring, Vaadin and Google App Engine [...]

By: Wolfgang Werner

Wolfgang Werner — Thu, 26 Aug 2010 12:11:00 +0000

I pretty much agree with Peter’s reply: I want to have a repeateable & portable (not necessarily between IDEs but between developers ) build. I want to be able to build it externally using a CI tool (hudson FTW!) and possibly measure code metrics w/ Sonar.

This said, I just threw out maven to move forward but I’m pretty sure I’ll regret it on the long run. I also think I’ll reconsider several times…

By: Peter Backx

Peter Backx — Thu, 12 Aug 2010 00:05:37 +0000

In all honesty, I've been asking myself that same question. There is a lot of overhead associated with creating the Maven pom (but the maintenance is not that bad).
There are a number of advantages: first it manages transitive dependencies, if I upgrade a library, I don't have to think about upgrading that libraries dependencies.
Second, it's easy to have a portable project. If I want to involve other developers, I can just give them the project and they're good to go. It doesn't matter whether they use Eclipse or not.
And finally, it creates a reproducible build, ideally suited for continuous builds and integration. Something which I'm not doing right now, but I envision I might at some point.
But you're absolutely right when it comes to small, one-off projects, you might not want to bother and just go ahead and put everything in Eclipse.

By: Asdf

Asdf — Sat, 31 Jul 2010 20:01:45 +0000

Obviously you can do everything by hand if you want to. You can hand-compile your project to java bytecode if you want.

If maven was an absolute necessity, then it would be included in gae, but it's not. However, it adds many nice features including the ones mentioned in his post.

I think this pom.xml is really nice and sweet. Thanks!

By: Chris Brind

Chris Brind — Thu, 29 Jul 2010 16:33:18 +0000

What's the main driver for using Maven here?

If you're in Eclipse anyway what's wrong with simply using the GAE plugin to create your project. As for managing dependencies, you know what those dependencies are, so just download them and put the jars in the WEB-INF/lib folder.

Maven just seems to add a lot of pain and fuzziness (to a lot of projects, not just this), so what am I missing?

By: Dimitrisli

Dimitrisli — Sun, 11 Jul 2010 07:10:51 +0000

Great article, spot on what I was looking for!

I have 'mvn clean' and 'mvn package' successfully from inside eclipse using m2eclipse. Now I am trying to run as a web application from the eclipse 'run configurations'. But I am getting the following:

Exception in thread "main" java.lang.NoClassDefFoundError: com/google/appengine/tools/development/DevAppServerMain
Caused by: java.lang.ClassNotFoundException: com.google.appengine.tools.development.DevAppServerMain
at java.net.URLClassLoader$1.run(URLClassLoader.java:202)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(URLClassLoader.java:190)
at java.lang.ClassLoader.loadClass(ClassLoader.java:307)
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:301)
at java.lang.ClassLoader.loadClass(ClassLoader.java:248)

By: Slscripters

Slscripters — Tue, 06 Jul 2010 20:30:23 +0000

Hi, do you have a solution for developing vaadin + spring + maven + googleappengine without using eclipse?

By: Peter Backx

Peter Backx — Wed, 26 May 2010 11:37:46 +0000

You're correct. Ivy is a great tool if you only want to do dependency management. You do have to combine it with some build toold (Ant, Gradle, maybe others). But I must confess its simplicity attracts me.