import java.util.List;
import java.util.Map;

import org.apache.maven.api.model.Model;
import org.apache.maven.model.building.ModelBuildingRequest;
import org.apache.maven.model.building.ModelProblem.Severity;
import org.apache.maven.model.building.ModelProblem.Version;
import org.apache.maven.model.building.ModelProblemCollector;
import org.apache.maven.model.building.ModelProblemCollectorRequest;
import org.apache.maven.model.path.PathTranslator;

import java.io.File;

import org.apache.maven.model.Activation;
import org.apache.maven.model.ActivationFile;
import org.apache.maven.model.Profile;
import org.apache.maven.model.building.ModelProblem.Severity;
import org.apache.maven.model.building.ModelProblem.Version;
import org.apache.maven.model.building.ModelProblemCollector;
import org.apache.maven.model.building.ModelProblemCollectorRequest;

public interface ModelProblemCollectorExt extends ModelProblemCollector {

    /**
     * The collected problems.
     * @return a list of model problems encountered, never {@code null}
     */
    List<ModelProblem> getProblems();

import org.apache.maven.internal.impl.InternalMavenSession;
import org.apache.maven.internal.impl.InternalSession;
import org.apache.maven.model.building.ModelBuildingException;
import org.apache.maven.model.building.ModelProblem;
import org.apache.maven.repository.RepositorySystem;
import org.apache.maven.repository.internal.MavenRepositorySystemUtils;
import org.apache.maven.session.scope.internal.SessionScope;

     * {@link ModelProblem.Severity#WARNING} and below are reported here. Problems with a higher severity level cause
     * the model builder to fail with a {@link ModelBuildingException}.
     *
     * @return The problems that were encountered during the model building, can be empty but never {@code null}.
     */
    List<ModelProblem> getProblems();

import java.util.List;
import java.util.regex.Pattern;

import org.apache.maven.model.Activation;
import org.apache.maven.model.Profile;
import org.apache.maven.model.building.ModelProblem.Severity;
import org.apache.maven.model.building.ModelProblem.Version;
import org.apache.maven.model.building.ModelProblemCollector;
import org.apache.maven.model.building.ModelProblemCollectorRequest;

import org.apache.maven.api.services.ProjectBuilderResult;
import org.apache.maven.api.services.Source;
import org.apache.maven.artifact.repository.ArtifactRepository;
import org.apache.maven.model.building.ModelProblem;
import org.apache.maven.model.building.ModelSource2;
import org.apache.maven.project.DefaultProjectBuildingRequest;
import org.apache.maven.project.ProjectBuildingException;

     *
     * @return the problems that were encountered during the project building, can be empty but never {@code null}
     */
    @Nonnull
    List<ModelProblem> getProblems();

    /**
     * Gets the children of this result.
     *
     * @return the children of this result, can be empty but never {@code null}
     */
    @Nonnull

            return "";
        }
    }

    /**
     * Gets the problems that caused this exception.
     *
     * @return The problems that caused this exception, never {@code null}.
     */
    public List<ModelProblem> getProblems() {
        if (result == null) {
            return Collections.emptyList();
        }
        return Collections.unmodifiableList(result.getProblems());
    }

        Result<? extends ProjectDependencyGraph> graphResult = graphBuilder.build(session);
        for (ModelProblem problem : graphResult.getProblems()) {
            if (problem.getSeverity() == ModelProblem.Severity.WARNING) {
                logger.warn(problem.getMessage());
            } else {
                logger.error(problem.getMessage());
            }
        }