ConcurrentHashMap<Object, Supplier<?>> cache;
        RepositoryCache repositoryCache = session != null ? session.getCache() : null;
        if (repositoryCache == null) {
            return new DefaultModelCache(new ConcurrentHashMap<>());
        } else {
            if (anew) {
                cache = new ConcurrentHashMap<>();
                repositoryCache.put(session, KEY, cache);

import java.nio.file.DirectoryNotEmptyException;
import java.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.Paths;
import java.nio.file.StandardCopyOption;
import java.util.*;
import java.util.concurrent.ConcurrentHashMap;
import java.util.stream.Collectors;
import java.util.stream.Stream;

import org.apache.maven.api.model.Model;
import org.apache.maven.api.services.Lookup;
import org.apache.maven.eventspy.EventSpy;

import javax.inject.Inject;
import javax.inject.Named;

import java.nio.file.Path;
import java.util.Map;
import java.util.Objects;
import java.util.Optional;
import java.util.concurrent.ConcurrentHashMap;
import java.util.stream.Stream;

import org.apache.maven.api.Artifact;
import org.apache.maven.api.annotations.Nonnull;
import org.apache.maven.api.di.SessionScoped;

            } else {
                this.modelPool = null;
                this.transformerContextBuilder = null;
            }
            this.parentCache = new ConcurrentHashMap<>();
            this.modelCache = DefaultModelCache.newInstance(session, true);
        }

        ExecutorService createExecutor(int parallelism) {
            //

import java.util.List;
import java.util.Map;
import java.util.NoSuchElementException;
import java.util.Objects;
import java.util.Optional;
import java.util.WeakHashMap;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.CopyOnWriteArrayList;
import java.util.function.Supplier;
import java.util.stream.Collectors;

import org.apache.maven.api.Artifact;
import org.apache.maven.api.ArtifactCoordinate;