this.rootDirectory = rootDirectory;
            return this;
        }

        public ProtoSession build() {
            return new Impl(userProperties, systemProperties, startTime, topDirectory, rootDirectory);
        }

        private static class Impl implements ProtoSession {
            private final Map<String, String> userProperties;
            private final Map<String, String> systemProperties;

     *
     * @param <P> the type of problem
     * @param protoSession the session containing configuration for the problem collector
     * @return a new problem collector instance
     */
    @Nonnull
    static <P extends BuilderProblem> ProblemCollector<P> create(@Nullable ProtoSession protoSession) {
        if (protoSession != null
                && protoSession.getUserProperties().containsKey(Constants.MAVEN_BUILDER_MAX_PROBLEMS)) {

import org.apache.maven.api.toolchain.ToolchainModel;

/**
 * The session to install / deploy / resolve artifacts and dependencies.
 *
 * @since 4.0.0
 */
@Experimental
@ThreadSafe
public interface Session extends ProtoSession {

    /**
     * Returns the current maven version.
     *
     * @return the maven version, never {@code null}
     */
    @Nonnull
    Version getMavenVersion();

    /**