APICover reports all signature polymorphic methods (http://download.java.net/java/jdk9/docs/api/java/lang/invoke/MethodHandle.html#sigpoly) as not covered, when the calls are clearly present in the code. This is likely caused by the fact that symbolic reference to such method has descriptor different from the one of the method declaration.

As of JDK 9 these methods are present in classes java.lang.invoke.MethodHandle and java.lang.invoke.VarHandle and can be recognized either by javadoc or by annotation @MethodHandle.PolymorphicSignature (annotation class is package-private).