*/
    void visitCollection(FileCollectionInternal.Source source, Iterable<File> contents);

    /**
     * Visits a file tree at a root file on the file system (potentially filtered).
     */
    void visitFileTree(File root, PatternSet patterns, FileTreeInternal fileTree);

    /**
     * Visits a file tree whose content is generated from the contents of a file.
     */

        public void visitFileTreeBackedByFile(File file, FileTreeInternal fileTree, FileSystemMirroringFileTree sourceTree) {
            cannotInferSourceRoots(fileTree);
        }

        @Override
        public void visitFileTree(File root, PatternSet patterns, FileTreeInternal fileTree) {
            // We need to add missing files as source roots, since the package name for deleted files provided by InputChanges also need to be determined.

                files.addAll(fileTree.getFiles());
            }

            @Override
            public void visitFileTree(File root, PatternSet patterns, FileTreeInternal fileTree) {
                addTreeContents(fileTree);
            }

            @Override

        return new PatternSet().include(includePattern).exclude(excludeSpec);
    }

    @Override
    public void visitStructure(MinimalFileTreeStructureVisitor visitor, FileTreeInternal owner) {
        visitor.visitFileTree(baseDir, getPatterns(), owner);
    }

    @Override
    public void visit(FileVisitor visitor) {
        doVisit(visitor, baseDir, new ArrayDeque<>(), 0, new AtomicBoolean());
    }

            }
        }

        override fun visitCollection(source: FileCollectionInternal.Source, contents: Iterable<File>) =
            throw UnsupportedOperationException()

        override fun visitFileTree(root: File, patterns: PatternSet, fileTree: FileTreeInternal) {
            roots.add(DirectoryTreeSpec(root, patterns))
        }

                    failOnInvalidOutputType(fileTree);
                }

                @Override
                public void visitFileTree(File root, PatternSet patterns, FileTreeInternal fileTree) {
                    // We could support an unfiltered DirectoryFileTree here as a cacheable root,

        return new DirectoryFileTree(getFile(), new PatternSet(), fileSystem);
    }

    @Override
    public void visitStructure(MinimalFileTreeStructureVisitor visitor, FileTreeInternal owner) {
        visitor.visitFileTree(getFile(), new PatternSet(), owner);
    }

    @Override
    public void visit(FileVisitor visitor) {
        FileVisitDetails fileVisitDetails = new FileVisitDetailsImpl(fileName, contentWriter, fileSystem);

        return DirectoryTrees.contains(fileSystem, this, file) && file.isFile();
    }

    @Override
    public void visitStructure(MinimalFileTreeStructureVisitor visitor, FileTreeInternal owner) {
        visitor.visitFileTree(dir, patternSet, owner);
    }

    @Override
    public void visit(FileVisitor visitor) {
        visitFrom(visitor, dir, RelativePath.EMPTY_ROOT, new AtomicBoolean());
    }

    /**

private
class ResolutionBackedFileCollectionSpec(val displayName: String, val lenient: Boolean, val elements: List<Any>)


private
abstract class AbstractVisitor : FileCollectionStructureVisitor {
    override fun visitFileTree(root: File, patterns: PatternSet, fileTree: FileTreeInternal) =
        unsupportedFileTree(fileTree)

                    contents.forEach(location -> taskInputs.add(location.getAbsolutePath()));
                }

                @Override
                public void visitFileTree(File root, PatternSet patterns, FileTreeInternal fileTree) {
                    if (patterns.isEmpty()) {
                        taskInputs.add(root.getAbsolutePath());
                    } else {