001package org.eclipse.aether.impl;
002
003/*
004 * Licensed to the Apache Software Foundation (ASF) under one
005 * or more contributor license agreements.  See the NOTICE file
006 * distributed with this work for additional information
007 * regarding copyright ownership.  The ASF licenses this file
008 * to you under the Apache License, Version 2.0 (the
009 * "License"); you may not use this file except in compliance
010 * with the License.  You may obtain a copy of the License at
011 * 
012 *  http://www.apache.org/licenses/LICENSE-2.0
013 * 
014 * Unless required by applicable law or agreed to in writing,
015 * software distributed under the License is distributed on an
016 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
017 * KIND, either express or implied.  See the License for the
018 * specific language governing permissions and limitations
019 * under the License.
020 */
021
022import java.lang.reflect.Constructor;
023import java.lang.reflect.Modifier;
024import java.util.ArrayList;
025import java.util.Collection;
026import java.util.Collections;
027import java.util.HashMap;
028import java.util.LinkedHashSet;
029import java.util.List;
030import java.util.Map;
031import static java.util.Objects.requireNonNull;
032
033import org.eclipse.aether.RepositorySystem;
034import org.eclipse.aether.internal.impl.DefaultRepositorySystemLifecycle;
035import org.eclipse.aether.internal.impl.LocalPathComposer;
036import org.eclipse.aether.internal.impl.DefaultLocalPathComposer;
037import org.eclipse.aether.internal.impl.DefaultArtifactResolver;
038import org.eclipse.aether.internal.impl.DefaultChecksumPolicyProvider;
039import org.eclipse.aether.internal.impl.DefaultTrackingFileManager;
040import org.eclipse.aether.internal.impl.TrackingFileManager;
041import org.eclipse.aether.internal.impl.checksum.DefaultChecksumAlgorithmFactorySelector;
042import org.eclipse.aether.internal.impl.collect.DefaultDependencyCollector;
043import org.eclipse.aether.internal.impl.DefaultDeployer;
044import org.eclipse.aether.internal.impl.DefaultFileProcessor;
045import org.eclipse.aether.internal.impl.DefaultInstaller;
046import org.eclipse.aether.internal.impl.DefaultLocalRepositoryProvider;
047import org.eclipse.aether.internal.impl.DefaultMetadataResolver;
048import org.eclipse.aether.internal.impl.DefaultOfflineController;
049import org.eclipse.aether.internal.impl.DefaultRemoteRepositoryManager;
050import org.eclipse.aether.internal.impl.DefaultRepositoryConnectorProvider;
051import org.eclipse.aether.internal.impl.DefaultRepositoryEventDispatcher;
052import org.eclipse.aether.internal.impl.DefaultRepositoryLayoutProvider;
053import org.eclipse.aether.internal.impl.DefaultRepositorySystem;
054import org.eclipse.aether.internal.impl.DefaultTransporterProvider;
055import org.eclipse.aether.internal.impl.DefaultUpdateCheckManager;
056import org.eclipse.aether.internal.impl.DefaultUpdatePolicyAnalyzer;
057import org.eclipse.aether.internal.impl.EnhancedLocalRepositoryManagerFactory;
058import org.eclipse.aether.internal.impl.Maven2RepositoryLayoutFactory;
059import org.eclipse.aether.internal.impl.SimpleLocalRepositoryManagerFactory;
060import org.eclipse.aether.internal.impl.filter.DefaultRemoteRepositoryFilterManager;
061import org.eclipse.aether.internal.impl.slf4j.Slf4jLoggerFactory;
062import org.eclipse.aether.internal.impl.synccontext.DefaultSyncContextFactory;
063import org.eclipse.aether.internal.impl.synccontext.named.NamedLockFactoryAdapterFactoryImpl;
064import org.eclipse.aether.internal.impl.synccontext.named.NamedLockFactoryAdapterFactory;
065import org.eclipse.aether.spi.connector.checksum.ChecksumAlgorithmFactorySelector;
066import org.eclipse.aether.spi.connector.checksum.ChecksumPolicyProvider;
067import org.eclipse.aether.spi.connector.layout.RepositoryLayoutFactory;
068import org.eclipse.aether.spi.connector.layout.RepositoryLayoutProvider;
069import org.eclipse.aether.spi.connector.transport.TransporterProvider;
070import org.eclipse.aether.spi.io.FileProcessor;
071import org.eclipse.aether.spi.localrepo.LocalRepositoryManagerFactory;
072import org.eclipse.aether.spi.locator.Service;
073import org.eclipse.aether.spi.locator.ServiceLocator;
074import org.eclipse.aether.spi.log.LoggerFactory;
075import org.eclipse.aether.spi.synccontext.SyncContextFactory;
076
077/**
078 * A simple service locator that is already setup with all components from this library. To acquire a complete
079 * repository system, clients need to add an artifact descriptor reader, a version resolver, a version range resolver
080 * and optionally some repository connector and transporter factories to access remote repositories. Once the locator is
081 * fully populated, the repository system can be created like this:
082 * 
083 * <pre>
084 * RepositorySystem repoSystem = serviceLocator.getService( RepositorySystem.class );
085 * </pre>
086 * 
087 * <em>Note:</em> This class is not thread-safe. Clients are expected to create the service locator and the repository
088 * system on a single thread.
089 *
090 * @deprecated Use some out-of-the-box DI implementation instead.
091 */
092@Deprecated
093public final class DefaultServiceLocator
094    implements ServiceLocator
095{
096
097    private class Entry<T>
098    {
099
100        private final Class<T> type;
101
102        private final Collection<Object> providers;
103
104        private List<T> instances;
105
106        Entry( Class<T> type )
107        {
108            this.type = requireNonNull( type, "service type cannot be null" );
109            providers = new LinkedHashSet<>( 8 );
110        }
111
112        public synchronized void setServices( T... services )
113        {
114            providers.clear();
115            if ( services != null )
116            {
117                for ( T service : services )
118                {
119                    providers.add( requireNonNull( service, "service instance cannot be null" ) );
120                }
121            }
122            instances = null;
123        }
124
125        public synchronized void setService( Class<? extends T> impl )
126        {
127            providers.clear();
128            addService( impl );
129        }
130
131        public synchronized void addService( Class<? extends T> impl )
132        {
133            providers.add( requireNonNull( impl, "implementation class cannot be null" ) );
134            instances = null;
135        }
136
137        public T getInstance()
138        {
139            List<T> instances = getInstances();
140            return instances.isEmpty() ? null : instances.get( 0 );
141        }
142
143        public synchronized List<T> getInstances()
144        {
145            if ( instances == null )
146            {
147                instances = new ArrayList<>( providers.size() );
148                for ( Object provider : providers )
149                {
150                    T instance;
151                    if ( provider instanceof Class )
152                    {
153                        instance = newInstance( (Class<?>) provider );
154                    }
155                    else
156                    {
157                        instance = type.cast( provider );
158                    }
159                    if ( instance != null )
160                    {
161                        instances.add( instance );
162                    }
163                }
164                instances = Collections.unmodifiableList( instances );
165            }
166            return instances;
167        }
168
169        private T newInstance( Class<?> impl )
170        {
171            try
172            {
173                Constructor<?> constr = impl.getDeclaredConstructor();
174                if ( !Modifier.isPublic( constr.getModifiers() ) )
175                {
176                    constr.setAccessible( true );
177                }
178                Object obj = constr.newInstance();
179
180                T instance = type.cast( obj );
181                if ( instance instanceof Service )
182                {
183                    ( (Service) instance ).initService( DefaultServiceLocator.this );
184                }
185                return instance;
186            }
187            catch ( Exception | LinkageError e )
188            {
189                serviceCreationFailed( type, impl, e );
190            }
191            return null;
192        }
193
194    }
195
196    private final Map<Class<?>, Entry<?>> entries;
197
198    private ErrorHandler errorHandler;
199
200    /**
201     * Creates a new service locator that already knows about all service implementations included this library.
202     */
203    public DefaultServiceLocator()
204    {
205        entries = new HashMap<>();
206
207        addService( RepositorySystem.class, DefaultRepositorySystem.class );
208        addService( ArtifactResolver.class, DefaultArtifactResolver.class );
209        addService( DependencyCollector.class, DefaultDependencyCollector.class );
210        addService( Deployer.class, DefaultDeployer.class );
211        addService( Installer.class, DefaultInstaller.class );
212        addService( MetadataResolver.class, DefaultMetadataResolver.class );
213        addService( RepositoryLayoutProvider.class, DefaultRepositoryLayoutProvider.class );
214        addService( RepositoryLayoutFactory.class, Maven2RepositoryLayoutFactory.class );
215        addService( TransporterProvider.class, DefaultTransporterProvider.class );
216        addService( ChecksumPolicyProvider.class, DefaultChecksumPolicyProvider.class );
217        addService( RepositoryConnectorProvider.class, DefaultRepositoryConnectorProvider.class );
218        addService( RemoteRepositoryManager.class, DefaultRemoteRepositoryManager.class );
219        addService( UpdateCheckManager.class, DefaultUpdateCheckManager.class );
220        addService( UpdatePolicyAnalyzer.class, DefaultUpdatePolicyAnalyzer.class );
221        addService( FileProcessor.class, DefaultFileProcessor.class );
222        addService( org.eclipse.aether.impl.SyncContextFactory.class,
223            org.eclipse.aether.internal.impl.synccontext.legacy.DefaultSyncContextFactory.class );
224        addService( SyncContextFactory.class, DefaultSyncContextFactory.class );
225        addService( RepositoryEventDispatcher.class, DefaultRepositoryEventDispatcher.class );
226        addService( OfflineController.class, DefaultOfflineController.class );
227        addService( LocalRepositoryProvider.class, DefaultLocalRepositoryProvider.class );
228        addService( LocalRepositoryManagerFactory.class, SimpleLocalRepositoryManagerFactory.class );
229        addService( LocalRepositoryManagerFactory.class, EnhancedLocalRepositoryManagerFactory.class );
230        addService( LoggerFactory.class, Slf4jLoggerFactory.class );
231        addService( TrackingFileManager.class, DefaultTrackingFileManager.class );
232        addService( ChecksumAlgorithmFactorySelector.class, DefaultChecksumAlgorithmFactorySelector.class );
233        addService( LocalPathComposer.class, DefaultLocalPathComposer.class );
234        addService( RemoteRepositoryFilterManager.class, DefaultRemoteRepositoryFilterManager.class );
235        addService( RepositorySystemLifecycle.class, DefaultRepositorySystemLifecycle.class );
236        addService( NamedLockFactoryAdapterFactory.class, NamedLockFactoryAdapterFactoryImpl.class );
237    }
238
239    private <T> Entry<T> getEntry( Class<T> type, boolean create )
240    {
241        @SuppressWarnings( "unchecked" )
242        Entry<T> entry = (Entry<T>) entries.get( requireNonNull( type, "service type cannot be null" ) );
243        if ( entry == null && create )
244        {
245            entry = new Entry<>( type );
246            entries.put( type, entry );
247        }
248        return entry;
249    }
250
251    /**
252     * Sets the implementation class for a service. The specified class must have a no-arg constructor (of any
253     * visibility). If the service implementation itself requires other services for its operation, it should implement
254     * {@link Service} to gain access to this service locator.
255     * 
256     * @param <T> The service type.
257     * @param type The interface describing the service, must not be {@code null}.
258     * @param impl The implementation class of the service, must not be {@code null}.
259     * @return This locator for chaining, never {@code null}.
260     */
261    public <T> DefaultServiceLocator setService( Class<T> type, Class<? extends T> impl )
262    {
263        getEntry( type, true ).setService( impl );
264        return this;
265    }
266
267    /**
268     * Adds an implementation class for a service. The specified class must have a no-arg constructor (of any
269     * visibility). If the service implementation itself requires other services for its operation, it should implement
270     * {@link Service} to gain access to this service locator.
271     * 
272     * @param <T> The service type.
273     * @param type The interface describing the service, must not be {@code null}.
274     * @param impl The implementation class of the service, must not be {@code null}.
275     * @return This locator for chaining, never {@code null}.
276     */
277    public <T> DefaultServiceLocator addService( Class<T> type, Class<? extends T> impl )
278    {
279        getEntry( type, true ).addService( impl );
280        return this;
281    }
282
283    /**
284     * Sets the instances for a service.
285     * 
286     * @param <T> The service type.
287     * @param type The interface describing the service, must not be {@code null}.
288     * @param services The instances of the service, may be {@code null} but must not contain {@code null} elements.
289     * @return This locator for chaining, never {@code null}.
290     */
291    public <T> DefaultServiceLocator setServices( Class<T> type, T... services )
292    {
293        getEntry( type, true ).setServices( services );
294        return this;
295    }
296
297    public <T> T getService( Class<T> type )
298    {
299        Entry<T> entry = getEntry( type, false );
300        return ( entry != null ) ? entry.getInstance() : null;
301    }
302
303    public <T> List<T> getServices( Class<T> type )
304    {
305        Entry<T> entry = getEntry( type, false );
306        return ( entry != null ) ? entry.getInstances() : null;
307    }
308
309    private void serviceCreationFailed( Class<?> type, Class<?> impl, Throwable exception )
310    {
311        if ( errorHandler != null )
312        {
313            errorHandler.serviceCreationFailed( type, impl, exception );
314        }
315    }
316
317    /**
318     * Sets the error handler to use.
319     * 
320     * @param errorHandler The error handler to use, may be {@code null} to ignore/swallow errors.
321     */
322    public void setErrorHandler( ErrorHandler errorHandler )
323    {
324        this.errorHandler = errorHandler;
325    }
326
327    /**
328     * A hook to customize the handling of errors encountered while locating a service implementation.
329     */
330    public abstract static class ErrorHandler
331    {
332
333        /**
334         * Handles errors during creation of a service. The default implemention does nothing.
335         * 
336         * @param type The interface describing the service, must not be {@code null}.
337         * @param impl The implementation class of the service, must not be {@code null}.
338         * @param exception The error that occurred while trying to instantiate the implementation class, must not be
339         *            {@code null}.
340         */
341        public void serviceCreationFailed( Class<?> type, Class<?> impl, Throwable exception )
342        {
343        }
344
345    }
346
347}