public void inherit(AnnotationType type) {
        if (superType != null) {
            throw new IllegalArgumentException("Already inherits type " + superType +
                                               ", multiple inheritance not currently supported.");
        }
        superType = type;
    }
WARNING! Only to be used by the configuration system and in unit tests. Not to be used in production code.

@param type the type to inherit from
document/src/main/java/com/yahoo/document/annotation/AnnotationType.java