Why does my Java app throw an error while loading CharSequence?

Issue

I see the error error while loading CharSequence, class file '/tmp/scala_ buildpack_build_dir/.jdk/jre/lib/rt.jar(java/lang/CharSequence.class)' is broken.

Resolution

This error occurs when you are trying to deploy a Scala 2.9 application on JDK 8. Set your Java version by adding java.runtime.version=1.7 in your system.properties file.