.inputStream(is)
                                .location(toolchainsSource.getLocation())
                                .strict(true)
                                .build());
            } catch (XmlReaderException e) {
                InputStream is = toolchainsSource.openStream();
                if (is == null) {
                    return PersistedToolchains.newInstance();
                }

            try (InputStream in = Files.newInputStream(userToolchainsFile.toPath())) {
                toolchains = new PersistedToolchains(new MavenToolchainsStaxReader().read(in));
            } catch (Exception e) {
                throw new MisconfiguredToolchainException(
                        "Cannot read toolchains file at " + userToolchainsFile.getAbsolutePath(), e);
            }

                @Override
                public List<BuilderProblem> getProblems() {
                    return new MappedList<>(result.getProblems(), MappedBuilderProblem::new);
                }
            };
        } catch (ToolchainsBuildingException e) {
            throw new ToolchainsBuilderException("Unable to build Toolchains", e);
        }
    }