return Collections.emptyList();
            }
        };
        ComponentUtil.register(requestHeaderService, RequestHeaderService.class.getCanonicalName());

        final SetOnce<Map<String, Object>> initParamMapSet = new SetOnce<>();
        WebConfig webConfig = new WebConfig();
        webConfig.setUserAgent(Constants.CRAWLING_USER_AGENT_PREFIX + "1.0" + Constants.CRAWLING_USER_AGENT_SUFFIX);

    default void add(ModelProblem problem) {
        getProblemCollector().reportProblem(problem);
    }

    ModelBuilderException newModelBuilderException();

    void setSource(String location);

    void setSource(Model model);

    String getSource();

    void setRootModel(Model model);

    Model getRootModel();

        DefaultProblemCollector collector = new DefaultProblemCollector(null);

        collector.add(null, "PROBLEM1", -1, -1, null);

        collector.setSource("SOURCE_PROBLEM2");
        collector.add(null, "PROBLEM2", -1, -1, null);

        collector.setSource("SOURCE_PROBLEM3");
        collector.add(null, "PROBLEM3", -1, -1, null);

        assertEquals("", collector.getProblems().get(0).getSource());

        assertEquals(1, collector2.getProblems().size());
    }

    @Test
    void testAddProblem() {
        ProblemCollector collector = ProblemCollectorFactory.newInstance(null);
        collector.setSource("pom.xml");
        collector.add(Problem.Severity.ERROR, "Error message", 10, 5, null);
        collector.add(Problem.Severity.WARNING, "Warning message", 15, 3, null);

        List<Problem> problems = collector.getProblems();

     * their source, but the next messages will use the new source.
     *
     * @param source a source
     */
    void setSource(String source);

    /**
     *
     * @return the collected Problems, never {@code null}
     */
    List<Problem> getProblems();

                e.getMessage());
    }

    @Test
    void testUnknownPosition() {
        ProblemCollector problemCollector = ProblemCollectorFactory.newInstance(null);
        problemCollector.setSource("SOURCE");
        problemCollector.add(Problem.Severity.ERROR, "MESSAGE", -1, -1, new Exception());
        ToolchainsBuildingException e = new ToolchainsBuildingException(problemCollector.getProblems());
        assertEquals(

    }

    @Override
    public List<ModelProblem> getProblems() {
        return problems;
    }

    public void setSource(String source) {
        this.source = source;
        this.sourceModel = null;
    }

    public void setSource(Model source) {
        this.sourceModel = source;
        this.source = null;

        if (rootModel == null) {
            rootModel = source;

                    source.put("timestamp", event.getTimestamp());
                    bulkRequest.add(client.prepareIndex().setIndex(indexName).setSource(source));
                }
                final BulkResponse response = bulkRequest.execute().actionGet(30_000L);
                if (response.hasFailures()) {

        this.problems = (problems != null) ? problems : new ArrayList<>();
    }

    public List<SettingsProblem> getProblems() {
        return problems;
    }

    public void setSource(String source) {
        this.source = source;
    }

    @Override
    public void add(SettingsProblem.Severity severity, String message, int line, int column, Exception cause) {

        Settings userSettings = readSettings(userSettingsSource, request, problems);

        settingsMerger.merge(userSettings, globalSettings, TrackableBase.GLOBAL_LEVEL);

        problems.setSource("");

        userSettings = interpolate(userSettings, request, problems);

        // for the special case of a drive-relative Windows path, make sure it's absolute to save plugins from trouble