private static String getUnqualifiedClassName(Class<?> erasedTargetType) {
        Class<?> declaringClass = erasedTargetType.getDeclaringClass();
        if (declaringClass == null) {
            return erasedTargetType.getSimpleName();
        }
        return getUnqualifiedClassName(declaringClass) + '$' + erasedTargetType.getSimpleName();
    }
Determine the unqualified name of the given class, e.g., as fall-back value for subtype reference with {@code JsonTypeInfo.Id.NAME}.

@param erasedTargetType class to produce unqualified class name for
@return simple class name, with declaring class's unqualified name as prefix for member classes
jsonschema-module-jackson/src/main/java/com/github/victools/jsonschema/module/jackson/JsonSubTypesResolver.java