how to compile widgetset using maven?

Hi all! I try to start developing with Vaadin 7 and maven.
And right at the start I’ve faced a stupid problem - when I run my project, I see this error:

Failed to load the widgetset: ./VAADIN/widgetsets/gemcenter.MyAppWidgetset/gemcenter.MyAppWidgetset.nocache.js?1426535771143

I have done “clean install”. Didn’t help.

I’ve added this to my pom.xml:

<dependency> <groupId>com.vaadin</groupId> <artifactId>vaadin-client-compiled</artifactId> <version>${vaadin.version}</version> </dependency> It didn’t help also.

I use Tomcat 7 as a server.
I know that I should compile the widgetset, but HOW?

Every time I try to use maven it does not help. All it does is it makes me angry.
What is wrong with my project? Or with my DNA?

I dont know why, but it works now.
Perhaps, a powerful mage just read this post and helped me.
Thank you.