Why doesn't my java compiler level match my installed project facet?

Question

I made a simple Java Google AppEngine application called Guestbook in Eclipse 3.7 and am trying to run it. However, I am encountering an error that lacks a quick fix:

Description Resource    Path    Location    Type Java compiler level does not match the version of the installed Java project facet. Guestbook       Unknown Faceted Project Problem (Java Version Mismatch) 

I tried navigating to Project | Properties to change my project facet. However, I could not find a setting that dealt with "facet."

What does "installed Java project facet" mean, and how do I fix this?

Answer 1

You can see your facets via Right click on your project->properties->Project Facets,

Here you can see my facets for an example web application:

I think your Java facet does not match with the installed one. I'm suspicious that facet is at version 1.5. Please check it.

Add-on:Open the Navigator view, expand the .settings folder, open the file org.eclipse.wst.common.project.facet.core.xml and manually set the Java version to 1.6.

Answer 2

Right click on your project->properties->Project Facets,

This will show your current version of java for your project facet.

In my case I had the correct version for my facet but not my compiler, So had to right click on project->properties->Java Compiler

Then under Compiler compliance level drop list and change to version of project facet.