/**
 * Collects problems that are encountered during settings building.
 *
 * @deprecated since 4.0.0, use {@link org.apache.maven.api.services} instead
 */
@Deprecated(since = "4.0.0")
public interface ProblemCollector {

    /**
     * Adds the specified problem.
     * Either message or exception is required
     *
     * @param severity The severity of the problem, must not be {@code null}.

    }

    @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(

 * @since 4.0.0
 */
@Experimental
public abstract class MavenBuilderException extends MavenException {

    /**
     * The collection of problems associated with this exception.
     */
    private final ProblemCollector<BuilderProblem> problems;

    /**
     * Constructs a new exception with the specified message and cause.
     * This constructor creates an empty problem collector.
     *
     * @param message the detail message

class ProblemCollectorFactoryTest {

    @Test
    void testNewInstance() {
        ProblemCollector collector1 = ProblemCollectorFactory.newInstance(null);

        Problem problem = new DefaultProblem("MESSAGE1", null, null, -1, -1, null);
        ProblemCollector collector2 = ProblemCollectorFactory.newInstance(Collections.singletonList(problem));

        assertNotSame(collector1, collector2);

import java.io.StringReader;
import java.io.StringWriter;
import java.util.Collections;
import java.util.List;
import java.util.Map;

import org.apache.maven.building.Problem;
import org.apache.maven.building.ProblemCollector;
import org.apache.maven.building.ProblemCollectorFactory;
import org.apache.maven.building.Source;
import org.apache.maven.toolchain.io.ToolchainsParseException;
import org.apache.maven.toolchain.io.ToolchainsReader;

    /**
     * The default implementation is not visible, create it with this factory
     *
     * @param problems starting set of problems, may be {@code null}
     * @return a new instance of a ProblemCollector
     */
    public static ProblemCollector newInstance(List<Problem> problems) {
        return new DefaultProblemCollector(problems);
    }

 * providing a simple error message, leaving the donkey work of creating a nice model problem to this component.
 *
 */
public interface ModelProblemCollector {

    ProblemCollector<ModelProblem> getProblemCollector();

    default boolean hasErrors() {
        return getProblemCollector().hasErrorProblems();
    }

    default boolean hasFatalErrors() {

     *
     * @param settings The settings to validate, must not be {@code null}.
     * @return The list of problems that were encountered, must not be {@code null}.
     */
    @Nonnull
    default ProblemCollector<BuilderProblem> validate(@Nonnull Settings settings) {
        return validate(settings, false);
    }

    /**
     * Validate the specified settings.
     *

    /**
     * Gets the problems that caused this exception.
     *
     * @return The problems that caused this exception, never {@code null}.
     */
    public ProblemCollector<ModelProblem> getProblemCollector() {
        if (result == null) {
            return ProblemCollector.empty();
        }
        return result.getProblemCollector();
    }

import org.apache.maven.api.services.ModelBuilderResult;
import org.apache.maven.api.services.ModelProblem;
import org.apache.maven.api.services.ModelSource;
import org.apache.maven.api.services.ProblemCollector;
import org.apache.maven.api.services.Source;
import org.junit.jupiter.api.Test;

import static org.junit.jupiter.api.Assertions.assertEquals;
import static org.junit.jupiter.api.Assertions.assertNotNull;

/**