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

    /**
     * Gets the result of the dependency resolution for the project.
     *
     * @return the result of the dependency resolution for the project
     */
    @Nonnull

 * 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 {

    /**
     * Enumeration of model versions that can be validated.
     * These versions correspond to different levels of validation that can be applied
     * during model building, based on the POM schema version.

import org.apache.maven.api.annotations.Nullable;
import org.apache.maven.api.cli.InvokerRequest;
import org.apache.maven.api.cli.Logger;
import org.apache.maven.api.cli.mvn.MavenOptions;
import org.apache.maven.api.services.BuilderProblem;
import org.apache.maven.api.services.Lookup;
import org.apache.maven.api.services.Sources;
import org.apache.maven.api.services.ToolchainsBuilder;
import org.apache.maven.api.services.ToolchainsBuilderRequest;

import org.apache.maven.api.cli.Logger;
import org.apache.maven.api.cli.cisupport.CIInfo;
import org.apache.maven.api.cli.logging.AccumulatingLogger;
import org.apache.maven.api.services.BuilderProblem;
import org.apache.maven.api.services.Lookup;
import org.apache.maven.api.services.MavenException;
import org.apache.maven.api.services.MessageBuilder;
import org.apache.maven.api.services.SettingsBuilder;

import org.apache.maven.api.services.ArtifactResolverException;
import org.apache.maven.api.services.ArtifactResolverRequest;
import org.apache.maven.api.services.ArtifactResolverResult;
import org.apache.maven.api.services.BuilderProblem.Severity;
import org.apache.maven.api.services.ModelBuilder;
import org.apache.maven.api.services.ModelBuilderException;
import org.apache.maven.api.services.ModelBuilderRequest;