private static Exprent replaceFunction(final InvocationExprent invexpr, final Exprent source) {
    FunctionExprent functionExprent = (FunctionExprent)((ExitExprent)source).getValue().copy();

    List<Exprent> lstParameters = invexpr.getParameters();

    FieldExprent fieldExprent = (FieldExprent)functionExprent.getLstOperands().get(0);
    if (fieldExprent.isStatic()) {
      if (!lstParameters.isEmpty()) {
        return null;
      }
      return functionExprent;
    }

    if (lstParameters.size() != 1) {
      return null;
    }

    fieldExprent.replaceExprent(fieldExprent.getInstance(), lstParameters.get(0));
    return functionExprent;
  }
private static Exprent replaceFunction(final InvocationExprent invexpr, final Exprent source)