public AbsoluteUnixPath resolve(Path relativePath) {
    if (relativePath.getRoot() != null) {
      throw new IllegalArgumentException("Cannot resolve against absolute Path: " + relativePath);
    }

    return AbsoluteUnixPath.fromPath(Paths.get(unixPath).resolve(relativePath));
  }
Resolves this path against another relative path (by the name elements of {@code
relativePath}).

@param relativePath the relative path to resolve against
@return a new {@link AbsoluteUnixPath} representing the resolved path
jib-build-plan/src/main/java/com/google/cloud/tools/jib/api/buildplan/AbsoluteUnixPath.java