* @return The formatted problem location or an empty string if unknown, never {@code null}.
     */
    public static String formatLocation(ModelProblem problem, String projectId) {
        StringBuilder buffer = new StringBuilder(256);

        if (!problem.getModelId().equals(projectId)) {
            buffer.append(problem.getModelId());

            if (!problem.getSource().isEmpty()) {

package org.apache.maven.api.services;

import org.apache.maven.api.annotations.Nonnull;

/**
 * Describes a problem that was encountered during model building. A problem can either be an exception that was thrown
 * or a simple string message. In addition, a problem carries a hint about its source, e.g. the POM file that exhibits
 * the problem.
 *
 */
public interface ModelProblem extends BuilderProblem {

    /**
     * Version
     */

* Jeśli nie rozumiesz pytania, poproś o więcej **szczegółów**.

### Odtwórz problem

W większości przypadków problem wynika z **autorskiego kodu** osoby pytającej.

Często pytający umieszczają tylko fragment kodu, niewystarczający do **odtworzenia problemu**.

        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());

     * @param line The one-based index of the line containing the problem or {@code -1} if unknown.
     * @param column The one-based index of the column containing the problem or {@code -1} if unknown.
     * @param cause The cause of the problem, may be {@code null}.
     */
    void add(SettingsProblem.Severity severity, String message, int line, int column, Exception cause);

    public void validate(Settings settings, SettingsProblemCollector problems) {
        validate(settings, false, problems);
    }

    @Override
    public void validate(Settings settings, boolean isProjectSettings, SettingsProblemCollector problems) {
        List<BuilderProblem> list = settingsBuilder.validate(settings.getDelegate(), isProjectSettings);
        for (BuilderProblem problem : list) {

        assertEquals("0 problems were encountered while building the effective toolchains" + LS, e.getMessage());
    }

    @Test
    void testOneProblem() {
        ProblemCollector problemCollector = ProblemCollectorFactory.newInstance(null);
        problemCollector.add(Problem.Severity.ERROR, "MESSAGE", 3, 5, new Exception());

    private List<SettingsProblem> convert(List<BuilderProblem> problems) {
        return problems.stream().map(this::convert).toList();
    }

    private SettingsProblem convert(BuilderProblem problem) {
        return new DefaultSettingsProblem(
                problem.getMessage(),
                SettingsProblem.Severity.valueOf(problem.getSeverity().name()),
                problem.getSource(),
                problem.getLineNumber(),

 */
package org.apache.maven.building;

/**
 * Describes a problem that was encountered during settings building. A problem can either be an exception that was
 * thrown or a simple string message. In addition, a problem carries a hint about its source, e.g. the settings file
 * that exhibits the problem.
 *
 */
class DefaultProblem implements Problem {

    private final String source;

    private final int lineNumber;

     */
    Exception getException();

    /**
     * Gets the message that describes this problem.
     *
     * @return The message describing this problem, never {@code null}.
     */
    String getMessage();

    /**
     * Gets the severity level of this problem.
     *
     * @return The severity level of this problem, never {@code null}.
     */