Java tutorial
/* * Copyright 2010 the original author or authors. * * Licensed 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.gradle.api.internal.file; import com.google.common.collect.ImmutableSet; import com.google.common.collect.Iterators; import org.gradle.api.file.FileCollection; import org.gradle.api.file.FileTree; import org.gradle.api.internal.file.collections.BuildDependenciesOnlyFileCollectionResolveContext; import org.gradle.api.internal.file.collections.DefaultFileCollectionResolveContext; import org.gradle.api.internal.file.collections.DirectoryFileTree; import org.gradle.api.internal.file.collections.FileCollectionContainer; import org.gradle.api.internal.file.collections.FileCollectionResolveContext; import org.gradle.api.internal.file.collections.ResolvableFileCollectionResolveContext; import org.gradle.api.internal.tasks.AbstractTaskDependency; import org.gradle.api.internal.tasks.TaskDependencyContainer; import org.gradle.api.internal.tasks.TaskDependencyResolveContext; import org.gradle.api.specs.Spec; import org.gradle.api.tasks.TaskDependency; import java.io.File; import java.util.ArrayList; import java.util.Collection; import java.util.Collections; import java.util.Iterator; import java.util.List; import java.util.Set; /** * A {@link org.gradle.api.file.FileCollection} that contains the union of zero or more file collections. Maintains file ordering. * * <p>The source file collections are calculated from the result of calling {@link #visitContents(FileCollectionResolveContext)}, and may be lazily created. * This also means that the source collections can be created using any representation supported by {@link FileCollectionResolveContext}. * </p> * * <p>The dependencies of this collection are calculated from the result of calling {@link #visitDependencies(TaskDependencyResolveContext)}.</p> */ public abstract class CompositeFileCollection extends AbstractFileCollection implements FileCollectionContainer, TaskDependencyContainer { @Override public Set<File> getFiles() { return getFiles(getSourceCollections()); } @Override public Iterator<File> iterator() { List<? extends FileCollectionInternal> sourceCollections = getSourceCollections(); switch (sourceCollections.size()) { case 0: return Iterators.emptyIterator(); case 1: return sourceCollections.get(0).iterator(); default: // Need to make sure we remove duplicates, so we can't just compose iterators from source collections return getFiles(sourceCollections).iterator(); } } private static Set<File> getFiles(List<? extends FileCollectionInternal> sourceCollections) { switch (sourceCollections.size()) { case 0: return Collections.emptySet(); case 1: return sourceCollections.get(0).getFiles(); default: ImmutableSet.Builder<File> builder = ImmutableSet.builder(); for (FileCollection collection : sourceCollections) { builder.addAll(collection); } return builder.build(); } } @Override public boolean contains(File file) { for (FileCollection collection : getSourceCollections()) { if (collection.contains(file)) { return true; } } return false; } @Override public boolean isEmpty() { for (FileCollection collection : getSourceCollections()) { if (!collection.isEmpty()) { return false; } } return true; } @Override protected void addAsResourceCollection(Object builder, String nodeName) { for (FileCollection fileCollection : getSourceCollections()) { fileCollection.addToAntBuilder(builder, nodeName, AntType.ResourceCollection); } } @Override protected Collection<DirectoryFileTree> getAsFileTrees() { List<DirectoryFileTree> fileTree = new ArrayList<DirectoryFileTree>(); for (FileCollection source : getSourceCollections()) { AbstractFileCollection collection = (AbstractFileCollection) source; fileTree.addAll(collection.getAsFileTrees()); } return fileTree; } @Override public FileTree getAsFileTree() { return new CompositeFileTree() { @Override public void visitContents(FileCollectionResolveContext context) { ResolvableFileCollectionResolveContext nested = context.newContext(); CompositeFileCollection.this.visitContents(nested); context.add(nested.resolveAsFileTrees()); } @Override public void visitDependencies(TaskDependencyResolveContext context) { CompositeFileCollection.this.visitDependencies(context); } @Override public String getDisplayName() { return CompositeFileCollection.this.getDisplayName(); } }; } @Override public FileCollection filter(final Spec<? super File> filterSpec) { return new CompositeFileCollection() { @Override public void visitContents(FileCollectionResolveContext context) { for (FileCollection collection : CompositeFileCollection.this.getSourceCollections()) { context.add(collection.filter(filterSpec)); } } @Override public void visitDependencies(TaskDependencyResolveContext context) { CompositeFileCollection.this.visitDependencies(context); } @Override public String getDisplayName() { return CompositeFileCollection.this.getDisplayName(); } }; } // This is final - use {@link TaskDependencyContainer#resolve} to provide the dependencies instead. @Override public final TaskDependency getBuildDependencies() { return new AbstractTaskDependency() { @Override public String toString() { return CompositeFileCollection.this.toString() + " dependencies"; } @Override public void visitDependencies(TaskDependencyResolveContext context) { CompositeFileCollection.this.visitDependencies(context); } }; } @Override public void visitDependencies(TaskDependencyResolveContext context) { BuildDependenciesOnlyFileCollectionResolveContext fileContext = new BuildDependenciesOnlyFileCollectionResolveContext( context); visitContents(fileContext); } protected List<? extends FileCollectionInternal> getSourceCollections() { DefaultFileCollectionResolveContext context = new DefaultFileCollectionResolveContext( new IdentityFileResolver()); visitContents(context); return context.resolveAsFileCollections(); } @Override public void registerWatchPoints(FileSystemSubset.Builder builder) { for (FileCollectionInternal files : getSourceCollections()) { files.registerWatchPoints(builder); } } @Override public void visitLeafCollections(FileCollectionLeafVisitor visitor) { for (FileCollectionInternal element : getSourceCollections()) { element.visitLeafCollections(visitor); } } }