/*
    * Licensed to the Apache Software Foundation (ASF) under one
    * or more contributor license agreements.  See the NOTICE file
    * distributed with this work for additional information
    * regarding copyright ownership.  The ASF licenses this file
    * to you under the Apache License, Version 2.0 (the
    * "License"); you may not use this file except in compliance
    * with the License.  You may obtain a copy of the License at
    *
   *   http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing,
   * software distributed under the License is distributed on an
   * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
   * KIND, either express or implied.  See the License for the
   * specific language governing permissions and limitations
   * under the License.
   */
  package org.eclipse.aether.supplier;
  
  import java.util.HashMap;
  import java.util.Map;
  import java.util.concurrent.atomic.AtomicBoolean;
  import java.util.function.Supplier;
  
  import org.apache.maven.model.building.DefaultModelBuilderFactory;
  import org.apache.maven.model.building.ModelBuilder;
  import org.apache.maven.repository.internal.DefaultArtifactDescriptorReader;
  import org.apache.maven.repository.internal.DefaultModelCacheFactory;
  import org.apache.maven.repository.internal.DefaultVersionRangeResolver;
  import org.apache.maven.repository.internal.DefaultVersionResolver;
  import org.apache.maven.repository.internal.ModelCacheFactory;
  import org.apache.maven.repository.internal.PluginsMetadataGeneratorFactory;
  import org.apache.maven.repository.internal.SnapshotMetadataGeneratorFactory;
  import org.apache.maven.repository.internal.VersionsMetadataGeneratorFactory;
  import org.eclipse.aether.RepositoryListener;
  import org.eclipse.aether.RepositorySystem;
  import org.eclipse.aether.connector.basic.BasicRepositoryConnectorFactory;
  import org.eclipse.aether.impl.ArtifactDescriptorReader;
  import org.eclipse.aether.impl.ArtifactResolver;
  import org.eclipse.aether.impl.DependencyCollector;
  import org.eclipse.aether.impl.Deployer;
  import org.eclipse.aether.impl.Installer;
  import org.eclipse.aether.impl.LocalRepositoryProvider;
  import org.eclipse.aether.impl.MetadataGeneratorFactory;
  import org.eclipse.aether.impl.MetadataResolver;
  import org.eclipse.aether.impl.OfflineController;
  import org.eclipse.aether.impl.RemoteRepositoryFilterManager;
  import org.eclipse.aether.impl.RemoteRepositoryManager;
  import org.eclipse.aether.impl.RepositoryConnectorProvider;
  import org.eclipse.aether.impl.RepositoryEventDispatcher;
  import org.eclipse.aether.impl.RepositorySystemLifecycle;
  import org.eclipse.aether.impl.UpdateCheckManager;
  import org.eclipse.aether.impl.UpdatePolicyAnalyzer;
  import org.eclipse.aether.impl.VersionRangeResolver;
  import org.eclipse.aether.impl.VersionResolver;
  import org.eclipse.aether.internal.impl.*;
  import org.eclipse.aether.internal.impl.checksum.DefaultChecksumAlgorithmFactorySelector;
  import org.eclipse.aether.internal.impl.checksum.Md5ChecksumAlgorithmFactory;
  import org.eclipse.aether.internal.impl.checksum.Sha1ChecksumAlgorithmFactory;
  import org.eclipse.aether.internal.impl.checksum.Sha256ChecksumAlgorithmFactory;
  import org.eclipse.aether.internal.impl.checksum.Sha512ChecksumAlgorithmFactory;
  import org.eclipse.aether.internal.impl.checksum.SparseDirectoryTrustedChecksumsSource;
  import org.eclipse.aether.internal.impl.checksum.SummaryFileTrustedChecksumsSource;
  import org.eclipse.aether.internal.impl.checksum.TrustedToProvidedChecksumsSourceAdapter;
  import org.eclipse.aether.internal.impl.collect.DefaultDependencyCollector;
  import org.eclipse.aether.internal.impl.collect.DependencyCollectorDelegate;
  import org.eclipse.aether.internal.impl.collect.bf.BfDependencyCollector;
  import org.eclipse.aether.internal.impl.collect.df.DfDependencyCollector;
  import org.eclipse.aether.internal.impl.filter.DefaultRemoteRepositoryFilterManager;
  import org.eclipse.aether.internal.impl.filter.GroupIdRemoteRepositoryFilterSource;
  import org.eclipse.aether.internal.impl.filter.PrefixesRemoteRepositoryFilterSource;
  import org.eclipse.aether.internal.impl.resolution.TrustedChecksumsArtifactResolverPostProcessor;
  import org.eclipse.aether.internal.impl.synccontext.DefaultSyncContextFactory;
  import org.eclipse.aether.internal.impl.synccontext.named.NameMapper;
  import org.eclipse.aether.internal.impl.synccontext.named.NameMappers;
  import org.eclipse.aether.internal.impl.synccontext.named.NamedLockFactoryAdapterFactory;
  import org.eclipse.aether.internal.impl.synccontext.named.NamedLockFactoryAdapterFactoryImpl;
  import org.eclipse.aether.internal.impl.transport.http.DefaultChecksumExtractor;
  import org.eclipse.aether.internal.impl.transport.http.Nx2ChecksumExtractor;
  import org.eclipse.aether.internal.impl.transport.http.XChecksumExtractor;
  import org.eclipse.aether.named.NamedLockFactory;
  import org.eclipse.aether.named.providers.FileLockNamedLockFactory;
  import org.eclipse.aether.named.providers.LocalReadWriteLockNamedLockFactory;
  import org.eclipse.aether.named.providers.LocalSemaphoreNamedLockFactory;
  import org.eclipse.aether.named.providers.NoopNamedLockFactory;
  import org.eclipse.aether.spi.artifact.ArtifactPredicateFactory;
  import org.eclipse.aether.spi.artifact.generator.ArtifactGeneratorFactory;
  import org.eclipse.aether.spi.checksums.ProvidedChecksumsSource;
  import org.eclipse.aether.spi.checksums.TrustedChecksumsSource;
  import org.eclipse.aether.spi.connector.RepositoryConnectorFactory;
  import org.eclipse.aether.spi.connector.checksum.ChecksumAlgorithmFactory;
  import org.eclipse.aether.spi.connector.checksum.ChecksumAlgorithmFactorySelector;
  import org.eclipse.aether.spi.connector.checksum.ChecksumPolicyProvider;
  import org.eclipse.aether.spi.connector.filter.RemoteRepositoryFilterSource;
  import org.eclipse.aether.spi.connector.layout.RepositoryLayoutFactory;
  import org.eclipse.aether.spi.connector.layout.RepositoryLayoutProvider;
  import org.eclipse.aether.spi.connector.transport.TransporterFactory;
  import org.eclipse.aether.spi.connector.transport.TransporterProvider;
 import org.eclipse.aether.spi.connector.transport.http.ChecksumExtractor;
 import org.eclipse.aether.spi.connector.transport.http.ChecksumExtractorStrategy;
 import org.eclipse.aether.spi.io.ChecksumProcessor;
 import org.eclipse.aether.spi.io.PathProcessor;
 import org.eclipse.aether.spi.localrepo.LocalRepositoryManagerFactory;
 import org.eclipse.aether.spi.resolution.ArtifactResolverPostProcessor;
 import org.eclipse.aether.spi.synccontext.SyncContextFactory;
 import org.eclipse.aether.transport.apache.ApacheTransporterFactory;
 import org.eclipse.aether.transport.file.FileTransporterFactory;
 import org.eclipse.aether.util.version.GenericVersionScheme;
 import org.eclipse.aether.version.VersionScheme;
 
 /**
  * A simple memorizing {@link Supplier} of {@link org.eclipse.aether.RepositorySystem} instance, that on first call
  * supplies lazily constructed instance, and on each subsequent call same instance. Hence, this instance should be
  * thrown away immediately once repository system was created and there is no need for more instances. If new
  * repository system instance needed, new instance of this class must be created. For proper shut down of returned
  * repository system instance(s) use {@link RepositorySystem#shutdown()} method on supplied instance(s).
  * <p>
  * Since Resolver 2.0 this class offers access to various components via public getters, and allows even partial object
  * graph construction.
  * <p>
  * Extend this class {@code createXXX()} methods and override to customize, if needed. The contract of this class makes
  * sure that these (potentially overridden) methods are invoked only once, and instance created by those methods are
  * memorized and kept as long as supplier instance is kept open.
  * <p>
  * This class is not thread safe and must be used from one thread only, while the constructed {@link RepositorySystem}
  * is thread safe.
  * <p>
  * Important: Given the instance of supplier memorizes the supplier {@link RepositorySystem} instance it supplies,
  * their lifecycle is shared as well: once supplied repository system is shut-down, this instance becomes closed as
  * well. Any subsequent {@code getXXX} method invocation attempt will fail with {@link IllegalStateException}.
  *
  * @since 1.9.15
  */
 public class RepositorySystemSupplier implements Supplier<RepositorySystem> {
     private final AtomicBoolean closed = new AtomicBoolean(false);
 
     public RepositorySystemSupplier() {}
 
     private void checkClosed() {
         if (closed.get()) {
             throw new IllegalStateException("Supplier is closed");
         }
     }
 
     private PathProcessor pathProcessor;
 
     public final PathProcessor getPathProcessor() {
         checkClosed();
         if (pathProcessor == null) {
             pathProcessor = createPathProcessor();
         }
         return pathProcessor;
     }
 
     protected PathProcessor createPathProcessor() {
         return new DefaultPathProcessor();
     }
 
     private ChecksumProcessor checksumProcessor;
 
     public final ChecksumProcessor getChecksumProcessor() {
         checkClosed();
         if (checksumProcessor == null) {
             checksumProcessor = createChecksumProcessor();
         }
         return checksumProcessor;
     }
 
     protected ChecksumProcessor createChecksumProcessor() {
         return new DefaultChecksumProcessor(getPathProcessor());
     }
 
     private TrackingFileManager trackingFileManager;
 
     public final TrackingFileManager getTrackingFileManager() {
         checkClosed();
         if (trackingFileManager == null) {
             trackingFileManager = createTrackingFileManager();
         }
         return trackingFileManager;
     }
 
     protected TrackingFileManager createTrackingFileManager() {
         return new DefaultTrackingFileManager();
     }
 
     private LocalPathComposer localPathComposer;
 
     public final LocalPathComposer getLocalPathComposer() {
         checkClosed();
         if (localPathComposer == null) {
             localPathComposer = createLocalPathComposer();
         }
         return localPathComposer;
     }
 
     protected LocalPathComposer createLocalPathComposer() {
         return new DefaultLocalPathComposer();
     }
 
     private LocalPathPrefixComposerFactory localPathPrefixComposerFactory;
 
     public final LocalPathPrefixComposerFactory getLocalPathPrefixComposerFactory() {
         checkClosed();
         if (localPathPrefixComposerFactory == null) {
             localPathPrefixComposerFactory = createLocalPathPrefixComposerFactory();
         }
         return localPathPrefixComposerFactory;
     }
 
     protected LocalPathPrefixComposerFactory createLocalPathPrefixComposerFactory() {
         return new DefaultLocalPathPrefixComposerFactory();
     }
 
     private RepositorySystemLifecycle repositorySystemLifecycle;
 
     public final RepositorySystemLifecycle getRepositorySystemLifecycle() {
         checkClosed();
         if (repositorySystemLifecycle == null) {
             repositorySystemLifecycle = createRepositorySystemLifecycle();
             repositorySystemLifecycle.addOnSystemEndedHandler(() -> closed.set(true));
         }
         return repositorySystemLifecycle;
     }
 
     protected RepositorySystemLifecycle createRepositorySystemLifecycle() {
         return new DefaultRepositorySystemLifecycle();
     }
 
     private OfflineController offlineController;
 
     public final OfflineController getOfflineController() {
         checkClosed();
         if (offlineController == null) {
             offlineController = createOfflineController();
         }
         return offlineController;
     }
 
     protected OfflineController createOfflineController() {
         return new DefaultOfflineController();
     }
 
     private UpdatePolicyAnalyzer updatePolicyAnalyzer;
 
     public final UpdatePolicyAnalyzer getUpdatePolicyAnalyzer() {
         checkClosed();
         if (updatePolicyAnalyzer == null) {
             updatePolicyAnalyzer = createUpdatePolicyAnalyzer();
         }
         return updatePolicyAnalyzer;
     }
 
     protected UpdatePolicyAnalyzer createUpdatePolicyAnalyzer() {
         return new DefaultUpdatePolicyAnalyzer();
     }
 
     private ChecksumPolicyProvider checksumPolicyProvider;
 
     public final ChecksumPolicyProvider getChecksumPolicyProvider() {
         checkClosed();
         if (checksumPolicyProvider == null) {
             checksumPolicyProvider = createChecksumPolicyProvider();
         }
         return checksumPolicyProvider;
     }
 
     protected ChecksumPolicyProvider createChecksumPolicyProvider() {
         return new DefaultChecksumPolicyProvider();
     }
 
     private UpdateCheckManager updateCheckManager;
 
     public final UpdateCheckManager getUpdateCheckManager() {
         checkClosed();
         if (updateCheckManager == null) {
             updateCheckManager = createUpdateCheckManager();
         }
         return updateCheckManager;
     }
 
     protected UpdateCheckManager createUpdateCheckManager() {
         return new DefaultUpdateCheckManager(getTrackingFileManager(), getUpdatePolicyAnalyzer(), getPathProcessor());
     }
 
     private Map<String, NamedLockFactory> namedLockFactories;
 
     public final Map<String, NamedLockFactory> getNamedLockFactories() {
         checkClosed();
         if (namedLockFactories == null) {
             namedLockFactories = createNamedLockFactories();
         }
         return namedLockFactories;
     }
 
     protected Map<String, NamedLockFactory> createNamedLockFactories() {
         HashMap<String, NamedLockFactory> result = new HashMap<>();
         result.put(NoopNamedLockFactory.NAME, new NoopNamedLockFactory());
         result.put(LocalReadWriteLockNamedLockFactory.NAME, new LocalReadWriteLockNamedLockFactory());
         result.put(LocalSemaphoreNamedLockFactory.NAME, new LocalSemaphoreNamedLockFactory());
         result.put(FileLockNamedLockFactory.NAME, new FileLockNamedLockFactory());
         return result;
     }
 
     private Map<String, NameMapper> nameMappers;
 
     public final Map<String, NameMapper> getNameMappers() {
         checkClosed();
         if (nameMappers == null) {
             nameMappers = createNameMappers();
         }
         return nameMappers;
     }
 
     protected Map<String, NameMapper> createNameMappers() {
         HashMap<String, NameMapper> result = new HashMap<>();
         result.put(NameMappers.STATIC_NAME, NameMappers.staticNameMapper());
         result.put(NameMappers.GAV_NAME, NameMappers.gavNameMapper());
         result.put(NameMappers.DISCRIMINATING_NAME, NameMappers.discriminatingNameMapper());
         result.put(NameMappers.FILE_GAV_NAME, NameMappers.fileGavNameMapper());
         result.put(NameMappers.FILE_HGAV_NAME, NameMappers.fileHashingGavNameMapper());
         return result;
     }
 
     private NamedLockFactoryAdapterFactory namedLockFactoryAdapterFactory;
 
     public final NamedLockFactoryAdapterFactory getNamedLockFactoryAdapterFactory() {
         checkClosed();
         if (namedLockFactoryAdapterFactory == null) {
             namedLockFactoryAdapterFactory = createNamedLockFactoryAdapterFactory();
         }
         return namedLockFactoryAdapterFactory;
     }
 
     protected NamedLockFactoryAdapterFactory createNamedLockFactoryAdapterFactory() {
         return new NamedLockFactoryAdapterFactoryImpl(
                 getNamedLockFactories(), getNameMappers(), getRepositorySystemLifecycle());
     }
 
     private SyncContextFactory syncContextFactory;
 
     public final SyncContextFactory getSyncContextFactory() {
         checkClosed();
         if (syncContextFactory == null) {
             syncContextFactory = createSyncContextFactory();
         }
         return syncContextFactory;
     }
 
     protected SyncContextFactory createSyncContextFactory() {
         return new DefaultSyncContextFactory(getNamedLockFactoryAdapterFactory());
     }
 
     private Map<String, ChecksumAlgorithmFactory> checksumAlgorithmFactories;
 
     public final Map<String, ChecksumAlgorithmFactory> getChecksumAlgorithmFactories() {
         checkClosed();
         if (checksumAlgorithmFactories == null) {
             checksumAlgorithmFactories = createChecksumAlgorithmFactories();
         }
         return checksumAlgorithmFactories;
     }
 
     protected Map<String, ChecksumAlgorithmFactory> createChecksumAlgorithmFactories() {
         HashMap<String, ChecksumAlgorithmFactory> result = new HashMap<>();
         result.put(Sha512ChecksumAlgorithmFactory.NAME, new Sha512ChecksumAlgorithmFactory());
         result.put(Sha256ChecksumAlgorithmFactory.NAME, new Sha256ChecksumAlgorithmFactory());
         result.put(Sha1ChecksumAlgorithmFactory.NAME, new Sha1ChecksumAlgorithmFactory());
         result.put(Md5ChecksumAlgorithmFactory.NAME, new Md5ChecksumAlgorithmFactory());
         return result;
     }
 
     private ChecksumAlgorithmFactorySelector checksumAlgorithmFactorySelector;
 
     public final ChecksumAlgorithmFactorySelector getChecksumAlgorithmFactorySelector() {
         checkClosed();
         if (checksumAlgorithmFactorySelector == null) {
             checksumAlgorithmFactorySelector = createChecksumAlgorithmFactorySelector();
         }
         return checksumAlgorithmFactorySelector;
     }
 
     protected ChecksumAlgorithmFactorySelector createChecksumAlgorithmFactorySelector() {
         return new DefaultChecksumAlgorithmFactorySelector(getChecksumAlgorithmFactories());
     }
 
     private ArtifactPredicateFactory artifactPredicateFactory;
 
     public final ArtifactPredicateFactory getArtifactPredicateFactory() {
         checkClosed();
         if (artifactPredicateFactory == null) {
             artifactPredicateFactory = createArtifactPredicateFactory();
         }
         return artifactPredicateFactory;
     }
 
     protected ArtifactPredicateFactory createArtifactPredicateFactory() {
         return new DefaultArtifactPredicateFactory(getChecksumAlgorithmFactorySelector());
     }
 
     private Map<String, RepositoryLayoutFactory> repositoryLayoutFactories;
 
     public final Map<String, RepositoryLayoutFactory> getRepositoryLayoutFactories() {
         checkClosed();
         if (repositoryLayoutFactories == null) {
             repositoryLayoutFactories = createRepositoryLayoutFactories();
         }
         return repositoryLayoutFactories;
     }
 
     protected Map<String, RepositoryLayoutFactory> createRepositoryLayoutFactories() {
         HashMap<String, RepositoryLayoutFactory> result = new HashMap<>();
         result.put(
                 Maven2RepositoryLayoutFactory.NAME,
                 new Maven2RepositoryLayoutFactory(
                         getChecksumAlgorithmFactorySelector(), getArtifactPredicateFactory()));
         return result;
     }
 
     private RepositoryLayoutProvider repositoryLayoutProvider;
 
     public final RepositoryLayoutProvider getRepositoryLayoutProvider() {
         checkClosed();
         if (repositoryLayoutProvider == null) {
             repositoryLayoutProvider = createRepositoryLayoutProvider();
         }
         return repositoryLayoutProvider;
     }
 
     protected RepositoryLayoutProvider createRepositoryLayoutProvider() {
         return new DefaultRepositoryLayoutProvider(getRepositoryLayoutFactories());
     }
 
     private LocalRepositoryProvider localRepositoryProvider;
 
     public final LocalRepositoryProvider getLocalRepositoryProvider() {
         checkClosed();
         if (localRepositoryProvider == null) {
             localRepositoryProvider = createLocalRepositoryProvider();
         }
         return localRepositoryProvider;
     }
 
     protected LocalRepositoryProvider createLocalRepositoryProvider() {
         LocalPathComposer localPathComposer = getLocalPathComposer();
         HashMap<String, LocalRepositoryManagerFactory> localRepositoryProviders = new HashMap<>(2);
         localRepositoryProviders.put(
                 SimpleLocalRepositoryManagerFactory.NAME, new SimpleLocalRepositoryManagerFactory(localPathComposer));
         localRepositoryProviders.put(
                 EnhancedLocalRepositoryManagerFactory.NAME,
                 new EnhancedLocalRepositoryManagerFactory(
                         localPathComposer, getTrackingFileManager(), getLocalPathPrefixComposerFactory()));
         return new DefaultLocalRepositoryProvider(localRepositoryProviders);
     }
 
     private RemoteRepositoryManager remoteRepositoryManager;
 
     public final RemoteRepositoryManager getRemoteRepositoryManager() {
         checkClosed();
         if (remoteRepositoryManager == null) {
             remoteRepositoryManager = createRemoteRepositoryManager();
         }
         return remoteRepositoryManager;
     }
 
     protected RemoteRepositoryManager createRemoteRepositoryManager() {
         return new DefaultRemoteRepositoryManager(getUpdatePolicyAnalyzer(), getChecksumPolicyProvider());
     }
 
     private Map<String, RemoteRepositoryFilterSource> remoteRepositoryFilterSources;
 
     public final Map<String, RemoteRepositoryFilterSource> getRemoteRepositoryFilterSources() {
         checkClosed();
         if (remoteRepositoryFilterSources == null) {
             remoteRepositoryFilterSources = createRemoteRepositoryFilterSources();
         }
         return remoteRepositoryFilterSources;
     }
 
     protected Map<String, RemoteRepositoryFilterSource> createRemoteRepositoryFilterSources() {
         HashMap<String, RemoteRepositoryFilterSource> result = new HashMap<>();
         result.put(
                 GroupIdRemoteRepositoryFilterSource.NAME,
                 new GroupIdRemoteRepositoryFilterSource(getRepositorySystemLifecycle()));
         result.put(
                 PrefixesRemoteRepositoryFilterSource.NAME,
                 new PrefixesRemoteRepositoryFilterSource(getRepositoryLayoutProvider()));
         return result;
     }
 
     private RemoteRepositoryFilterManager remoteRepositoryFilterManager;
 
     public final RemoteRepositoryFilterManager getRemoteRepositoryFilterManager() {
         checkClosed();
         if (remoteRepositoryFilterManager == null) {
             remoteRepositoryFilterManager = createRemoteRepositoryFilterManager();
         }
         return remoteRepositoryFilterManager;
     }
 
     protected RemoteRepositoryFilterManager createRemoteRepositoryFilterManager() {
         return new DefaultRemoteRepositoryFilterManager(getRemoteRepositoryFilterSources());
     }
 
     private Map<String, RepositoryListener> repositoryListeners;
 
     public final Map<String, RepositoryListener> getRepositoryListeners() {
         checkClosed();
         if (repositoryListeners == null) {
             repositoryListeners = createRepositoryListeners();
         }
         return repositoryListeners;
     }
 
     protected Map<String, RepositoryListener> createRepositoryListeners() {
         return new HashMap<>();
     }
 
     private RepositoryEventDispatcher repositoryEventDispatcher;
 
     public final RepositoryEventDispatcher getRepositoryEventDispatcher() {
         checkClosed();
         if (repositoryEventDispatcher == null) {
             repositoryEventDispatcher = createRepositoryEventDispatcher();
         }
         return repositoryEventDispatcher;
     }
 
     protected RepositoryEventDispatcher createRepositoryEventDispatcher() {
         return new DefaultRepositoryEventDispatcher(getRepositoryListeners());
     }
 
     private Map<String, TrustedChecksumsSource> trustedChecksumsSources;
 
     public final Map<String, TrustedChecksumsSource> getTrustedChecksumsSources() {
         checkClosed();
         if (trustedChecksumsSources == null) {
             trustedChecksumsSources = createTrustedChecksumsSources();
         }
         return trustedChecksumsSources;
     }
 
     protected Map<String, TrustedChecksumsSource> createTrustedChecksumsSources() {
         HashMap<String, TrustedChecksumsSource> result = new HashMap<>();
         result.put(
                 SparseDirectoryTrustedChecksumsSource.NAME,
                 new SparseDirectoryTrustedChecksumsSource(getChecksumProcessor(), getLocalPathComposer()));
         result.put(
                 SummaryFileTrustedChecksumsSource.NAME,
                 new SummaryFileTrustedChecksumsSource(getLocalPathComposer(), getRepositorySystemLifecycle()));
         return result;
     }
 
     private Map<String, ProvidedChecksumsSource> providedChecksumsSources;
 
     public final Map<String, ProvidedChecksumsSource> getProvidedChecksumsSources() {
         checkClosed();
         if (providedChecksumsSources == null) {
             providedChecksumsSources = createProvidedChecksumsSources();
         }
         return providedChecksumsSources;
     }
 
     protected Map<String, ProvidedChecksumsSource> createProvidedChecksumsSources() {
         HashMap<String, ProvidedChecksumsSource> result = new HashMap<>();
         result.put(
                 TrustedToProvidedChecksumsSourceAdapter.NAME,
                 new TrustedToProvidedChecksumsSourceAdapter(getTrustedChecksumsSources()));
         return result;
     }
 
     private Map<String, ChecksumExtractorStrategy> checksumExtractorStrategies;
 
     public final Map<String, ChecksumExtractorStrategy> getChecksumExtractorStrategies() {
         checkClosed();
         if (checksumExtractorStrategies == null) {
             checksumExtractorStrategies = createChecksumExtractorStrategies();
         }
         return checksumExtractorStrategies;
     }
 
     protected Map<String, ChecksumExtractorStrategy> createChecksumExtractorStrategies() {
         HashMap<String, ChecksumExtractorStrategy> result = new HashMap<>();
         result.put(XChecksumExtractor.NAME, new XChecksumExtractor());
         result.put(Nx2ChecksumExtractor.NAME, new Nx2ChecksumExtractor());
         return result;
     }
 
     private ChecksumExtractor checksumExtractor;
 
     public final ChecksumExtractor getChecksumExtractor() {
         checkClosed();
         if (checksumExtractor == null) {
             checksumExtractor = createChecksumExtractor();
         }
         return checksumExtractor;
     }
 
     protected ChecksumExtractor createChecksumExtractor() {
         return new DefaultChecksumExtractor(getChecksumExtractorStrategies());
     }
 
     private Map<String, TransporterFactory> transporterFactories;
 
     public final Map<String, TransporterFactory> getTransporterFactories() {
         checkClosed();
         if (transporterFactories == null) {
             transporterFactories = createTransporterFactories();
         }
         return transporterFactories;
     }
 
     protected Map<String, TransporterFactory> createTransporterFactories() {
         HashMap<String, TransporterFactory> result = new HashMap<>();
         result.put(FileTransporterFactory.NAME, new FileTransporterFactory());
         result.put(ApacheTransporterFactory.NAME, new ApacheTransporterFactory(getChecksumExtractor()));
         return result;
     }
 
     private TransporterProvider transporterProvider;
 
     public final TransporterProvider getTransporterProvider() {
         checkClosed();
         if (transporterProvider == null) {
             transporterProvider = createTransporterProvider();
         }
         return transporterProvider;
     }
 
     protected TransporterProvider createTransporterProvider() {
         return new DefaultTransporterProvider(getTransporterFactories());
     }
 
     private BasicRepositoryConnectorFactory basicRepositoryConnectorFactory;
 
     public final BasicRepositoryConnectorFactory getBasicRepositoryConnectorFactory() {
         checkClosed();
         if (basicRepositoryConnectorFactory == null) {
             basicRepositoryConnectorFactory = createBasicRepositoryConnectorFactory();
         }
         return basicRepositoryConnectorFactory;
     }
 
     protected BasicRepositoryConnectorFactory createBasicRepositoryConnectorFactory() {
         return new BasicRepositoryConnectorFactory(
                 getTransporterProvider(),
                 getRepositoryLayoutProvider(),
                 getChecksumPolicyProvider(),
                 getChecksumProcessor(),
                 getProvidedChecksumsSources());
     }
 
     private Map<String, RepositoryConnectorFactory> repositoryConnectorFactories;
 
     public final Map<String, RepositoryConnectorFactory> getRepositoryConnectorFactories() {
         checkClosed();
         if (repositoryConnectorFactories == null) {
             repositoryConnectorFactories = createRepositoryConnectorFactories();
         }
         return repositoryConnectorFactories;
     }
 
     protected Map<String, RepositoryConnectorFactory> createRepositoryConnectorFactories() {
         HashMap<String, RepositoryConnectorFactory> result = new HashMap<>();
         result.put(BasicRepositoryConnectorFactory.NAME, getBasicRepositoryConnectorFactory());
         return result;
     }
 
     private RepositoryConnectorProvider repositoryConnectorProvider;
 
     public final RepositoryConnectorProvider getRepositoryConnectorProvider() {
         checkClosed();
         if (repositoryConnectorProvider == null) {
             repositoryConnectorProvider = createRepositoryConnectorProvider();
         }
         return repositoryConnectorProvider;
     }
 
     protected RepositoryConnectorProvider createRepositoryConnectorProvider() {
         return new DefaultRepositoryConnectorProvider(
                 getRepositoryConnectorFactories(), getRemoteRepositoryFilterManager());
     }
 
     private Installer installer;
 
     public final Installer getInstaller() {
         checkClosed();
         if (installer == null) {
             installer = createInstaller();
         }
         return installer;
     }
 
     protected Installer createInstaller() {
         return new DefaultInstaller(
                 getPathProcessor(),
                 getRepositoryEventDispatcher(),
                 getArtifactGeneratorFactories(),
                 getMetadataGeneratorFactories(),
                 getSyncContextFactory());
     }
 
     private Deployer deployer;
 
     public final Deployer getDeployer() {
         checkClosed();
         if (deployer == null) {
             deployer = createDeployer();
         }
         return deployer;
     }
 
     protected Deployer createDeployer() {
         return new DefaultDeployer(
                 getPathProcessor(),
                 getRepositoryEventDispatcher(),
                 getRepositoryConnectorProvider(),
                 getRemoteRepositoryManager(),
                 getUpdateCheckManager(),
                 getArtifactGeneratorFactories(),
                 getMetadataGeneratorFactories(),
                 getSyncContextFactory(),
                 getOfflineController());
     }
 
     private Map<String, DependencyCollectorDelegate> dependencyCollectorDelegates;
 
     public final Map<String, DependencyCollectorDelegate> getDependencyCollectorDelegates() {
         checkClosed();
         if (dependencyCollectorDelegates == null) {
             dependencyCollectorDelegates = createDependencyCollectorDelegates();
         }
         return dependencyCollectorDelegates;
     }
 
     protected Map<String, DependencyCollectorDelegate> createDependencyCollectorDelegates() {
         RemoteRepositoryManager remoteRepositoryManager = getRemoteRepositoryManager();
         ArtifactDescriptorReader artifactDescriptorReader = getArtifactDescriptorReader();
         VersionRangeResolver versionRangeResolver = getVersionRangeResolver();
         HashMap<String, DependencyCollectorDelegate> result = new HashMap<>();
         result.put(
                 DfDependencyCollector.NAME,
                 new DfDependencyCollector(remoteRepositoryManager, artifactDescriptorReader, versionRangeResolver));
         result.put(
                 BfDependencyCollector.NAME,
                 new BfDependencyCollector(remoteRepositoryManager, artifactDescriptorReader, versionRangeResolver));
         return result;
     }
 
     private DependencyCollector dependencyCollector;
 
     public final DependencyCollector getDependencyCollector() {
         checkClosed();
         if (dependencyCollector == null) {
             dependencyCollector = createDependencyCollector();
         }
         return dependencyCollector;
     }
 
     protected DependencyCollector createDependencyCollector() {
         return new DefaultDependencyCollector(getDependencyCollectorDelegates());
     }
 
     private Map<String, ArtifactResolverPostProcessor> artifactResolverPostProcessors;
 
     public final Map<String, ArtifactResolverPostProcessor> getArtifactResolverPostProcessors() {
         checkClosed();
         if (artifactResolverPostProcessors == null) {
             artifactResolverPostProcessors = createArtifactResolverPostProcessors();
         }
         return artifactResolverPostProcessors;
     }
 
     protected Map<String, ArtifactResolverPostProcessor> createArtifactResolverPostProcessors() {
         HashMap<String, ArtifactResolverPostProcessor> result = new HashMap<>();
         result.put(
                 TrustedChecksumsArtifactResolverPostProcessor.NAME,
                 new TrustedChecksumsArtifactResolverPostProcessor(
                         getChecksumAlgorithmFactorySelector(), getTrustedChecksumsSources()));
         return result;
     }
 
     private ArtifactResolver artifactResolver;
 
     public final ArtifactResolver getArtifactResolver() {
         checkClosed();
         if (artifactResolver == null) {
             artifactResolver = createArtifactResolver();
         }
         return artifactResolver;
     }
 
     protected ArtifactResolver createArtifactResolver() {
         return new DefaultArtifactResolver(
                 getPathProcessor(),
                 getRepositoryEventDispatcher(),
                 getVersionResolver(),
                 getUpdateCheckManager(),
                 getRepositoryConnectorProvider(),
                 getRemoteRepositoryManager(),
                 getSyncContextFactory(),
                 getOfflineController(),
                 getArtifactResolverPostProcessors(),
                 getRemoteRepositoryFilterManager());
     }
 
     private MetadataResolver metadataResolver;
 
     public final MetadataResolver getMetadataResolver() {
         checkClosed();
         if (metadataResolver == null) {
             metadataResolver = createMetadataResolver();
         }
         return metadataResolver;
     }
 
     protected MetadataResolver createMetadataResolver() {
         return new DefaultMetadataResolver(
                 getRepositoryEventDispatcher(),
                 getUpdateCheckManager(),
                 getRepositoryConnectorProvider(),
                 getRemoteRepositoryManager(),
                 getSyncContextFactory(),
                 getOfflineController(),
                 getRemoteRepositoryFilterManager(),
                 getPathProcessor());
     }
 
     private VersionScheme versionScheme;
 
     public final VersionScheme getVersionScheme() {
         checkClosed();
         if (versionScheme == null) {
             versionScheme = createVersionScheme();
         }
         return versionScheme;
     }
 
     protected VersionScheme createVersionScheme() {
         return new GenericVersionScheme();
     }
 
     private Map<String, ArtifactGeneratorFactory> artifactGeneratorFactories;
 
     public final Map<String, ArtifactGeneratorFactory> getArtifactGeneratorFactories() {
         checkClosed();
         if (artifactGeneratorFactories == null) {
             artifactGeneratorFactories = createArtifactGeneratorFactories();
         }
         return artifactGeneratorFactories;
     }
 
     protected Map<String, ArtifactGeneratorFactory> createArtifactGeneratorFactories() {
         // by default none, this is extension point
         return new HashMap<>();
     }
 
     // Maven provided
 
     private Map<String, MetadataGeneratorFactory> metadataGeneratorFactories;
 
     public final Map<String, MetadataGeneratorFactory> getMetadataGeneratorFactories() {
         checkClosed();
         if (metadataGeneratorFactories == null) {
             metadataGeneratorFactories = createMetadataGeneratorFactories();
         }
         return metadataGeneratorFactories;
     }
 
     protected Map<String, MetadataGeneratorFactory> createMetadataGeneratorFactories() {
         // from maven-resolver-provider
         HashMap<String, MetadataGeneratorFactory> result = new HashMap<>();
         result.put(PluginsMetadataGeneratorFactory.NAME, new PluginsMetadataGeneratorFactory());
         result.put(VersionsMetadataGeneratorFactory.NAME, new VersionsMetadataGeneratorFactory());
         result.put(SnapshotMetadataGeneratorFactory.NAME, new SnapshotMetadataGeneratorFactory());
         return result;
     }
 
     private ArtifactDescriptorReader artifactDescriptorReader;
 
     public final ArtifactDescriptorReader getArtifactDescriptorReader() {
         checkClosed();
         if (artifactDescriptorReader == null) {
             artifactDescriptorReader = createArtifactDescriptorReader();
         }
         return artifactDescriptorReader;
     }
 
     protected ArtifactDescriptorReader createArtifactDescriptorReader() {
         // from maven-resolver-provider
         return new DefaultArtifactDescriptorReader(
                 getRemoteRepositoryManager(),
                 getVersionResolver(),
                 getVersionRangeResolver(),
                 getArtifactResolver(),
                 getModelBuilder(),
                 getRepositoryEventDispatcher(),
                 getModelCacheFactory());
     }
 
     private VersionResolver versionResolver;
 
     public final VersionResolver getVersionResolver() {
         checkClosed();
         if (versionResolver == null) {
             versionResolver = createVersionResolver();
         }
         return versionResolver;
     }
 
     protected VersionResolver createVersionResolver() {
         // from maven-resolver-provider
         return new DefaultVersionResolver(
                 getMetadataResolver(), getSyncContextFactory(), getRepositoryEventDispatcher());
     }
 
     private VersionRangeResolver versionRangeResolver;
 
     public final VersionRangeResolver getVersionRangeResolver() {
         checkClosed();
         if (versionRangeResolver == null) {
             versionRangeResolver = createVersionRangeResolver();
         }
         return versionRangeResolver;
     }
 
     protected VersionRangeResolver createVersionRangeResolver() {
         // from maven-resolver-provider
         return new DefaultVersionRangeResolver(
                 getMetadataResolver(), getSyncContextFactory(), getRepositoryEventDispatcher());
     }
 
     private ModelBuilder modelBuilder;
 
     public final ModelBuilder getModelBuilder() {
         checkClosed();
         if (modelBuilder == null) {
             modelBuilder = createModelBuilder();
         }
         return modelBuilder;
     }
 
     protected ModelBuilder createModelBuilder() {
         // from maven-model-builder
         return new DefaultModelBuilderFactory().newInstance();
     }
 
     private ModelCacheFactory modelCacheFactory;
 
     public final ModelCacheFactory getModelCacheFactory() {
         checkClosed();
         if (modelCacheFactory == null) {
             modelCacheFactory = createModelCacheFactory();
         }
         return modelCacheFactory;
     }
 
     protected ModelCacheFactory createModelCacheFactory() {
         // from maven-resolver-provider
         return new DefaultModelCacheFactory();
     }
 
     private RepositorySystem repositorySystem;
 
     public final RepositorySystem getRepositorySystem() {
         checkClosed();
         if (repositorySystem == null) {
             repositorySystem = createRepositorySystem();
         }
         return repositorySystem;
     }
 
     protected RepositorySystem createRepositorySystem() {
         return new DefaultRepositorySystem(
                 getVersionResolver(),
                 getVersionRangeResolver(),
                 getArtifactResolver(),
                 getMetadataResolver(),
                 getArtifactDescriptorReader(),
                 getDependencyCollector(),
                 getInstaller(),
                 getDeployer(),
                 getLocalRepositoryProvider(),
                 getSyncContextFactory(),
                 getRemoteRepositoryManager(),
                 getRepositorySystemLifecycle());
     }
 
     @Override
     public RepositorySystem get() {
         return getRepositorySystem();
     }
 }