This release is still a ways down the road but so it's on our radar I've set up a Jenkins build with the first milestone release of GeoServer 2.8 using GeoTools 14.0

http://blog.geoserver.org/2015/05/29/geoserver-2-8-m0-released/
GeoServer 2.8 is scheduled for September release.
This is milestone release of GeoServer made in conjunction with GeoTools 14-M0.

(Internal Link)
http://jenkins-ui.ec2.internal:8080/jenkins/view/geowave-cdh/job/geowave-cdh5-geoserver-2.8.0/1/console

[ERROR] /home/jenkins/workspace/geowave-cdh5-geoserver-2.8.0/extensions/adapters/raster/src/main/java/mil/nga/giat/geowave/adapter/raster/adapter/RasterDataAdapter.java:[1016,10] error: cannot find symbol
[ERROR] class SimplifiedGridSampleDimension
/home/jenkins/workspace/geowave-cdh5-geoserver-2.8.0/extensions/adapters/raster/src/main/java/mil/nga/giat/geowave/adapter/raster/adapter/RasterDataAdapter.java:[1586,6] error: no suitable constructor found for Category(InternationalString,Color[],NumberRange,NumberRange)
[ERROR]
/home/jenkins/workspace/geowave-cdh5-geoserver-2.8.0/extensions/adapters/raster/src/main/java/mil/nga/giat/geowave/adapter/raster/adapter/RasterDataAdapter.java:[1651,2] error: method does not override or implement a method from a supertype
[ERROR] /home/jenkins/workspace/geowave-cdh5-geoserver-2.8.0/extensions/adapters/raster/src/main/java/mil/nga/giat/geowave/adapter/raster/adapter/RasterDataAdapter.java:[1653,15] error: cannot find symbol
[ERROR] method getSampleToGeophysics()
/home/jenkins/workspace/geowave-cdh5-geoserver-2.8.0/extensions/adapters/raster/src/main/java/mil/nga/giat/geowave/adapter/raster/adapter/RasterDataAdapter.java:[1671,2] error: method does not override or implement a method from a supertype
[ERROR] /home/jenkins/workspace/geowave-cdh5-geoserver-2.8.0/extensions/adapters/raster/src/main/java/mil/nga/giat/geowave/adapter/raster/RasterUtils.java:[944,20] error: no suitable constructor found for Category(CharSequence,,NumberRange,NumberRange)
[ERROR] NumberRange,boolean) is not applicable