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

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.

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.

its simple.. in Problems infotab, rightclick on error desc and select quickfix... choose facet version upgrade..