Can't run my application

I worked with my app. Suddenly my compyter reloaded. I run my project again and got:

INFO: Requested resource [VAADIN/widgetsets/]
not found from filesystem or through class loader. Add widgetset and/or theme JAR to your classpath or add files to WebContent/VAADIN folder.

How I can fix it? Help me please(

That *.nocache.js file is from the widgetset. You need to compile it again. If you are using Maven run mvn clean install