@Nonnull
	public String getCommon(@Nonnull String first, @Nonnull String second) {
		// Easy base cases
		if (OBJECT.equals(first) || OBJECT.equals(second))
			return OBJECT;
		if (first.equals(second))
			return first;

		// Try with the first name
		InheritanceVertex vertex = getVertex(first);
		if (vertex != null)
			return getCommon(vertex, first, second);

		// Try again but with the other name
		vertex = getVertex(second);
		if (vertex != null)
			return getCommon(vertex, second, first);

		// Neither is resolvable
		return OBJECT;
	}
@param first
		First class name.
@param second
		Second class name.

@return Common parent of the classes.
recaf-core/src/main/java/software/coley/recaf/services/inheritance/InheritanceGraph.java