[SOLVED] Cannot change version of project facet Dynamic Web Module to 3.0?

Cannot change version of project facet Dynamic Web Module to 3.0?

I am using maven to create a dynamic webapp in Eclipse. I added some folders like src/test/java and src/test/resources. Also I changed the library in Java Build Path to obtain the JavaSE-1.7. It's all OK up to here.

When I tried to change the Projects Facet Dynamic Web Module something went wrong. I had change the Java to 1.7 in the same place. And it still told me, cannot change version of project facet Dynamic Web Module to 3.0.

I have changed everything that would effect the changing I think.

Solution

I updated my web.xml

<web-app xmlns="http://java.sun.com/xml/ns/javaee"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://java.sun.com/xml/ns/javaee 
          http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd"
    version="3.0">
    <display-name>Servlet 3.0 Web Application</display-name>
</web-app>

and then just Maven -> Update Project ...