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.
 *
 */
public interface Problem {

    /**
     * The different severity levels for a problem, in decreasing order.
     */
    enum Severity {

        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("SOURCE_PROBLEM2", collector.getProblems().get(1).getSource());

    }

    @Override
    public void add(ModelProblem problem) {
        problems.add(problem);

        severities.add(problem.getSeverity());
    }

    public void addAll(Collection<ModelProblem> problems) {
        this.problems.addAll(problems);

        for (ModelProblem problem : problems) {
            severities.add(problem.getSeverity());
        }
    }

    @Override

     * @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()) {

        problem = new DefaultProblem(null, null, "", -1, -1, null);
        assertEquals("", problem.getSource());

        problem = new DefaultProblem(null, null, "SOURCE", -1, -1, null);
        assertEquals("SOURCE", problem.getSource());
    }

    @Test
    void testGetLocation() {
        DefaultProblem problem = new DefaultProblem(null, null, null, -1, -1, null);
        assertEquals("", problem.getLocation());

- component not found

Plugins:
- plugin metadata missing
- plugin metadata retrieval problem
- plugin artifact missing
- plugin artifact retrieval problem
- plugin dependency metadata missing
- plugin dependency metadata retrieval problem
- plugin configuration problem
- plugin execution failure due to something that is know to possibly go wrong (like compilation failure)

                                problem.getLineNumber() > 0 ? "line " + problem.getLineNumber() : "",
                                problem.getColumnNumber() > 0 ? "column " + problem.getColumnNumber() : "")
                        .filter(s -> !s.isEmpty())
                        .collect(Collectors.joining(", "));
                if (!loc.isEmpty()) {

                    return new MappedCollection<>(res.getProblems(), this::toProblem);
                }

                private BuilderProblem toProblem(ModelProblem problem) {
                    return new BuilderProblem() {
                        @Override
                        public String getSource() {
                            return problem.getSource();
                        }

                        @Override

import java.util.ArrayList;
import java.util.List;

/**
 * Collects problems that are encountered during settings building.
 *
 */
class DefaultProblemCollector implements ProblemCollector {

    private final List<Problem> problems;

    private String source;

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

    @Override

* 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**.