line = br.readLine();
            }
        } catch (IOException e) {
            throw new UncheckedIOException(e);
        }

        if (!errorsForFile.isEmpty()) {
            errors.put(sourceFile, errorsForFile);
        }
    }

    private void gatherDeadLinksInLine(File sourceFile, String line, int lineNumber, List<Error> errorsForFile) {
        Matcher matcher = linkPattern.matcher(line);