validateStringNotEmpty(problems, "mirrors.mirror.id", mirror.getId(), mirror.getUrl());

                validateBannedCharacters(
                        problems, "mirrors.mirror.id", Severity.WARNING, mirror.getId(), null, ILLEGAL_REPO_ID_CHARS);

                if ("local".equals(mirror.getId())) {
                    addViolation(
                            problems,
                            Severity.WARNING,

 files for the current project. if yes. then I'm able to find projects that
 can be offered to be opened together with the current project.
 problems with the current solution are:
 1. information is duplicate. once in POM's dependencies and once in the
 maven.multiproject.includes property.
 2. it works without problems only for projects with relative paths, e.g., from
 one CVS repository.. for projects from multiple SCM repositories it's harder

     *
     * @param severity the severity level to get problems for
     * @return a stream of problems with the specified severity
     */
    @Nonnull
    Stream<P> problems(BuilderProblem.Severity severity);

    /**
     * Creates an "empty" problem collector that doesn't store any problems.
     *
     * @param <P> the type of problem
     * @return an empty problem collector
     */
    @Nonnull

        return null;
    }

    static String toMessage(String modelId, List<ModelProblem> problems) {
        StringWriter buffer = new StringWriter(1024);

        PrintWriter writer = new PrintWriter(buffer);

        writer.print(problems.size());
        writer.print((problems.size() == 1) ? " problem was " : " problems were ");
        writer.print("encountered while building the effective model");

    private List<Problem> problems;

    /**
     * Default constructor
     *
     * @param effectiveToolchains the merged toolchains, may not be {@code null}
     * @param problems the problems while building the effectiveToolchains, if any.
     */
    public DefaultToolchainsBuildingResult(PersistedToolchains effectiveToolchains, List<Problem> problems) {
        this.effectiveToolchains = effectiveToolchains;

    }

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

    public DefaultModelBuildingResult setProblems(List<ModelProblem> problems) {
        if (problems != null) {
            this.problems = new ArrayList<>(problems);
        } else {
            this.problems.clear();
        }

        return this;
    }

        repo.setUrl("http://xxx.xxx.com");
        problems = new SimpleProblemCollector();
        validator.validate(model, problems);
        assertEquals(1, problems.messages.size());

        repo.setId("xxx");
        problems = new SimpleProblemCollector();
        validator.validate(model, problems);
        assertEquals(0, problems.messages.size());
    }

    @Test
    void testValidateMirror() throws Exception {

        this.securityDispatcher = securityDispatcher;
    }

    @Override
    public SettingsDecryptionResult decrypt(SettingsDecryptionRequest request) {
        List<SettingsProblem> problems = new ArrayList<>();

        List<Server> servers = new ArrayList<>();

        for (Server server : request.getServers()) {
            server = server.clone();

            String password = server.getPassword();

    private List<Proxy> proxies;

    private List<SettingsProblem> problems;

    DefaultSettingsDecryptionResult(List<Server> servers, List<Proxy> proxies, List<SettingsProblem> problems) {
        this.servers = (servers != null) ? servers : new ArrayList<>();
        this.proxies = (proxies != null) ? proxies : new ArrayList<>();
        this.problems = (problems != null) ? problems : new ArrayList<>();
    }

    @Override

        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();
        assertEquals(2, problems.size(), "Should collect both problems");
        assertEquals(Problem.Severity.ERROR, problems.get(0).getSeverity(), "First problem should be ERROR");