Java tutorial
/* * Copyright (C) 2014 Hari Krishna Dulipudi * Copyright (C) 2013 The Android Open Source Project * * 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 dev.dworks.apps.anexplorer.provider; import android.annotation.SuppressLint; import android.annotation.TargetApi; import android.content.ContentProviderClient; import android.content.ContentResolver; import android.content.Context; import android.content.Intent; import android.content.res.AssetFileDescriptor; import android.database.Cursor; import android.graphics.Point; import android.net.Uri; import android.os.Binder; import android.os.Build; import android.os.Environment; import android.os.FileObserver; import android.os.Handler; import android.os.ParcelFileDescriptor; import android.support.v4.os.EnvironmentCompat; import android.text.TextUtils; import android.util.Log; import com.google.common.collect.Lists; import com.google.common.collect.Maps; import java.io.File; import java.io.FileInputStream; import java.io.FileNotFoundException; import java.io.IOException; import java.util.ArrayList; import java.util.HashMap; import java.util.Map; import java.util.zip.ZipEntry; import java.util.zip.ZipInputStream; import dev.dworks.apps.anexplorer.BuildConfig; import dev.dworks.apps.anexplorer.R; import dev.dworks.apps.anexplorer.cursor.MatrixCursor; import dev.dworks.apps.anexplorer.cursor.MatrixCursor.RowBuilder; import dev.dworks.apps.anexplorer.libcore.io.IoUtils; import dev.dworks.apps.anexplorer.misc.CancellationSignal; import dev.dworks.apps.anexplorer.misc.ContentProviderClientCompat; import dev.dworks.apps.anexplorer.misc.FileUtils; import dev.dworks.apps.anexplorer.misc.MimePredicate; import dev.dworks.apps.anexplorer.misc.MimeTypes; import dev.dworks.apps.anexplorer.misc.StorageUtils; import dev.dworks.apps.anexplorer.misc.StorageVolume; import dev.dworks.apps.anexplorer.misc.Utils; import dev.dworks.apps.anexplorer.model.DocumentsContract; import dev.dworks.apps.anexplorer.model.DocumentsContract.Document; import dev.dworks.apps.anexplorer.model.DocumentsContract.Root; import dev.dworks.apps.anexplorer.model.GuardedBy; import dev.dworks.apps.anexplorer.setting.SettingsActivity; import static dev.dworks.apps.anexplorer.model.DocumentInfo.getCursorString; @SuppressLint("DefaultLocale") public class ExternalStorageProvider extends StorageProvider { private static final String TAG = "ExternalStorage"; private static final boolean LOG_INOTIFY = false; public static final String AUTHORITY = BuildConfig.APPLICATION_ID + ".externalstorage.documents"; public static final String DOWNLOAD_AUTHORITY = "com.android.providers.downloads.documents"; // docId format: root:path/to/file private static final String[] DEFAULT_ROOT_PROJECTION = new String[] { Root.COLUMN_ROOT_ID, Root.COLUMN_FLAGS, Root.COLUMN_ICON, Root.COLUMN_TITLE, Root.COLUMN_DOCUMENT_ID, Root.COLUMN_AVAILABLE_BYTES, Root.COLUMN_TOTAL_BYTES, Root.COLUMN_PATH, }; private static final String[] DEFAULT_DOCUMENT_PROJECTION = new String[] { Document.COLUMN_DOCUMENT_ID, Document.COLUMN_MIME_TYPE, Document.COLUMN_PATH, Document.COLUMN_DISPLAY_NAME, Document.COLUMN_LAST_MODIFIED, Document.COLUMN_FLAGS, Document.COLUMN_SIZE, Document.COLUMN_SUMMARY, }; private boolean showFilesHidden; private static class RootInfo { public String rootId; public int flags; public String title; public String docId; public String path; } public static final String ROOT_ID_PRIMARY_EMULATED = "primary"; public static final String ROOT_ID_SECONDARY = "secondary"; public static final String ROOT_ID_PHONE = "phone"; public static final String ROOT_ID_DOWNLOAD = "download"; public static final String ROOT_ID_BLUETOOTH = "bluetooth"; public static final String ROOT_ID_APP_BACKUP = "app_backup"; public static final String ROOT_ID_HIDDEN = "hidden"; public static final String ROOT_ID_BOOKMARK = "bookmark"; private static final String DIR_ROOT = "/"; private Handler mHandler; private final Object mRootsLock = new Object(); @GuardedBy("mRootsLock") private ArrayList<RootInfo> mRoots; @GuardedBy("mRootsLock") private HashMap<String, RootInfo> mIdToRoot; @GuardedBy("mRootsLock") private HashMap<String, File> mIdToPath; @GuardedBy("mObservers") private Map<File, DirectoryObserver> mObservers = Maps.newHashMap(); @Override public boolean onCreate() { mHandler = new Handler(); mRoots = Lists.newArrayList(); mIdToRoot = Maps.newLinkedHashMap(); mIdToPath = Maps.newLinkedHashMap(); updateVolumes(); updateSettings(); return true; } public void updateVolumes() { synchronized (mRootsLock) { updateVolumesLocked(); includeOtherRoot(); includeBookmarkRoot(); } } @TargetApi(Build.VERSION_CODES.KITKAT) private void updateVolumesLocked() { mRoots.clear(); mIdToPath.clear(); mIdToRoot.clear(); int count = 0; StorageUtils storageUtils = new StorageUtils(getContext()); for (StorageVolume volume : storageUtils.getStorageMounts()) { final File path = volume.getPathFile(); String state = EnvironmentCompat.getStorageState(path); final boolean mounted = Environment.MEDIA_MOUNTED.equals(state) || Environment.MEDIA_MOUNTED_READ_ONLY.equals(state); if (!mounted) continue; final String rootId; final String title; if (volume.isPrimary && volume.isEmulated) { rootId = ROOT_ID_PRIMARY_EMULATED; title = getContext().getString(R.string.root_internal_storage); } else if (volume.getUuid() != null) { rootId = ROOT_ID_SECONDARY + volume.getLabel(); String label = volume.getLabel(); title = !TextUtils.isEmpty(label) ? label : getContext().getString(R.string.root_external_storage) + (count > 0 ? " " + count : ""); count++; } else { Log.d(TAG, "Missing UUID for " + volume.getPath() + "; skipping"); continue; } if (mIdToPath.containsKey(rootId)) { Log.w(TAG, "Duplicate UUID " + rootId + "; skipping"); continue; } try { if (null == path.listFiles()) { continue; } mIdToPath.put(rootId, path); final RootInfo root = new RootInfo(); root.rootId = rootId; root.flags = Root.FLAG_SUPPORTS_CREATE | Root.FLAG_SUPPORTS_EDIT | Root.FLAG_LOCAL_ONLY | Root.FLAG_ADVANCED | Root.FLAG_SUPPORTS_SEARCH | Root.FLAG_SUPPORTS_IS_CHILD; root.title = title; root.docId = getDocIdForFile(path); root.path = path.getPath(); mRoots.add(root); mIdToRoot.put(rootId, root); } catch (FileNotFoundException e) { throw new IllegalStateException(e); } } Log.d(TAG, "After updating volumes, found " + mRoots.size() + " active roots"); getContext().getContentResolver().notifyChange(DocumentsContract.buildRootsUri(AUTHORITY), null, false); } private void includeOtherRoot() { try { final String rootId = ROOT_ID_PHONE; final File path = new File(DIR_ROOT); mIdToPath.put(rootId, path); final RootInfo root = new RootInfo(); root.rootId = rootId; root.flags = Root.FLAG_LOCAL_ONLY | Root.FLAG_ADVANCED | Root.FLAG_SUPER_ADVANCED | Root.FLAG_SUPPORTS_SEARCH; root.title = getContext().getString(R.string.root_phone_storage); root.docId = getDocIdForFile(path); root.path = path.getPath(); mRoots.add(root); mIdToRoot.put(rootId, root); } catch (FileNotFoundException e) { e.printStackTrace(); } try { final String rootId = ROOT_ID_DOWNLOAD; final File path = Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_DOWNLOADS); mIdToPath.put(rootId, path); final RootInfo root = new RootInfo(); root.rootId = rootId; root.flags = Root.FLAG_SUPPORTS_CREATE | Root.FLAG_SUPPORTS_EDIT | Root.FLAG_LOCAL_ONLY | Root.FLAG_ADVANCED | Root.FLAG_SUPPORTS_SEARCH; root.title = getContext().getString(R.string.root_downloads); root.docId = getDocIdForFile(path); root.path = path.getPath(); mRoots.add(root); mIdToRoot.put(rootId, root); } catch (FileNotFoundException e) { e.printStackTrace(); } try { final String rootId = ROOT_ID_APP_BACKUP; final File path = Environment.getExternalStoragePublicDirectory("AppBackup"); mIdToPath.put(rootId, path); final RootInfo root = new RootInfo(); root.rootId = rootId; root.flags = Root.FLAG_SUPPORTS_CREATE | Root.FLAG_SUPPORTS_EDIT | Root.FLAG_LOCAL_ONLY | Root.FLAG_ADVANCED | Root.FLAG_SUPPORTS_SEARCH; root.title = getContext().getString(R.string.root_app_backup); root.docId = getDocIdForFile(path); root.path = path.getPath(); mRoots.add(root); mIdToRoot.put(rootId, root); } catch (FileNotFoundException e) { e.printStackTrace(); } try { final String rootId = ROOT_ID_BLUETOOTH; File path = Environment.getExternalStoragePublicDirectory("Bluetooth"); if (null == path) { path = Environment.getExternalStoragePublicDirectory("Download/Bluetooth"); } if (null != path) { mIdToPath.put(rootId, path); final RootInfo root = new RootInfo(); root.rootId = rootId; root.flags = Root.FLAG_SUPPORTS_CREATE | Root.FLAG_SUPPORTS_EDIT | Root.FLAG_LOCAL_ONLY | Root.FLAG_ADVANCED | Root.FLAG_SUPPORTS_SEARCH; root.title = getContext().getString(R.string.root_bluetooth); root.docId = getDocIdForFile(path); root.path = path.getPath(); mRoots.add(root); mIdToRoot.put(rootId, root); } } catch (FileNotFoundException e) { e.printStackTrace(); } } private void includeBookmarkRoot() { Cursor cursor = null; try { cursor = getContext().getContentResolver().query(ExplorerProvider.buildBookmark(), null, null, null, null); while (cursor.moveToNext()) { try { final String rootId = ROOT_ID_BOOKMARK + " " + getCursorString(cursor, ExplorerProvider.BookmarkColumns.ROOT_ID); final File path = new File(getCursorString(cursor, ExplorerProvider.BookmarkColumns.PATH)); mIdToPath.put(rootId, path); final RootInfo root = new RootInfo(); root.rootId = rootId; root.flags = Root.FLAG_SUPPORTS_CREATE | Root.FLAG_SUPPORTS_EDIT | Root.FLAG_LOCAL_ONLY | Root.FLAG_ADVANCED | Root.FLAG_SUPPORTS_SEARCH; root.title = getCursorString(cursor, ExplorerProvider.BookmarkColumns.TITLE); root.docId = getDocIdForFile(path); root.path = path.getPath(); mRoots.add(root); mIdToRoot.put(rootId, root); } catch (FileNotFoundException e) { e.printStackTrace(); } } } catch (Exception e) { Log.w(TAG, "Failed to load some roots from " + ExplorerProvider.AUTHORITY + ": " + e); } finally { IoUtils.closeQuietly(cursor); } } public void updateSettings() { showFilesHidden = SettingsActivity.getDisplayFileHidden(getContext()); } private static String[] resolveRootProjection(String[] projection) { return projection != null ? projection : DEFAULT_ROOT_PROJECTION; } private static String[] resolveDocumentProjection(String[] projection) { return projection != null ? projection : DEFAULT_DOCUMENT_PROJECTION; } public static void notifyRootsChanged(Context context) { context.getContentResolver().notifyChange(DocumentsContract.buildRootsUri(AUTHORITY), null, false); } public static void updateVolumes(Context context) { final ContentProviderClient client = ContentProviderClientCompat.acquireUnstableContentProviderClient( context.getContentResolver(), ExternalStorageProvider.AUTHORITY); try { ((ExternalStorageProvider) client.getLocalContentProvider()).updateVolumes(); } finally { ContentProviderClientCompat.releaseQuietly(client); } } public static boolean isDownloadAuthority(Intent intent) { if (null != intent.getData()) { String authority = intent.getData().getAuthority(); return ExternalStorageProvider.DOWNLOAD_AUTHORITY.equals(authority); } return false; } private String getDocIdForFile(File file) throws FileNotFoundException { String path = file.getAbsolutePath(); // Find the most-specific root path Map.Entry<String, File> mostSpecific = null; synchronized (mRootsLock) { for (Map.Entry<String, File> root : mIdToPath.entrySet()) { final String rootPath = root.getValue().getPath(); if (path.startsWith(rootPath) && (mostSpecific == null || rootPath.length() > mostSpecific.getValue().getPath().length())) { mostSpecific = root; } } } if (mostSpecific == null) { throw new FileNotFoundException("Failed to find root that contains " + path); } // Start at first char of path under root final String rootPath = mostSpecific.getValue().getPath(); if (rootPath.equals(path)) { path = ""; } else if (rootPath.endsWith("/")) { path = path.substring(rootPath.length()); } else { path = path.substring(rootPath.length() + 1); } return mostSpecific.getKey() + ':' + path; } private File getFileForDocId(String docId) throws FileNotFoundException { final int splitIndex = docId.indexOf(':', 1); final String tag = docId.substring(0, splitIndex); final String path = docId.substring(splitIndex + 1); File target; synchronized (mRootsLock) { target = mIdToPath.get(tag); } if (target == null) { throw new FileNotFoundException("No root for " + tag); } if (!target.exists()) { target.mkdirs(); } target = new File(target, path); if (!target.exists()) { throw new FileNotFoundException("Missing file for " + docId + " at " + target); } return target; } private void includeFile(MatrixCursor result, String docId, File file) throws FileNotFoundException { if (docId == null) { docId = getDocIdForFile(file); } else { file = getFileForDocId(docId); } int flags = 0; if (file.canWrite()) { if (file.isDirectory()) { flags |= Document.FLAG_DIR_SUPPORTS_CREATE; flags |= Document.FLAG_SUPPORTS_DELETE; flags |= Document.FLAG_SUPPORTS_RENAME; } else { flags |= Document.FLAG_SUPPORTS_WRITE; flags |= Document.FLAG_SUPPORTS_DELETE; flags |= Document.FLAG_SUPPORTS_RENAME; } flags |= Document.FLAG_SUPPORTS_DELETE | Document.FLAG_SUPPORTS_EDIT; } final String displayName = file.getName(); if (!showFilesHidden && !TextUtils.isEmpty(displayName)) { if (displayName.charAt(0) == '.') { return; } } final String mimeType = getTypeForFile(file); if (MimePredicate.mimeMatches(MimePredicate.VISUAL_MIMES, mimeType)) { flags |= Document.FLAG_SUPPORTS_THUMBNAIL; } final RowBuilder row = result.newRow(); row.add(Document.COLUMN_DOCUMENT_ID, docId); row.add(Document.COLUMN_DISPLAY_NAME, displayName); row.add(Document.COLUMN_SIZE, file.length()); row.add(Document.COLUMN_MIME_TYPE, mimeType); row.add(Document.COLUMN_PATH, file.getAbsolutePath()); row.add(Document.COLUMN_FLAGS, flags); if (file.isDirectory() && null != file.list()) { row.add(Document.COLUMN_SUMMARY, FileUtils.formatFileCount(file.list().length)); } // Only publish dates reasonably after epoch long lastModified = file.lastModified(); if (lastModified > 31536000000L) { row.add(Document.COLUMN_LAST_MODIFIED, lastModified); } } private void includeZIPFile(MatrixCursor result, String docId, ZipEntry zipEntry) throws FileNotFoundException { int flags = 0; final String displayName = zipEntry.getName(); final String mimeType = ""; //getTypeForFile(zipEntry); final RowBuilder row = result.newRow(); row.add(Document.COLUMN_DOCUMENT_ID, docId); row.add(Document.COLUMN_DISPLAY_NAME, displayName); row.add(Document.COLUMN_SIZE, zipEntry.getSize()); row.add(Document.COLUMN_MIME_TYPE, mimeType); row.add(Document.COLUMN_PATH, "");//zipEntry.getAbsolutePath()); row.add(Document.COLUMN_FLAGS, flags); if (zipEntry.isDirectory()) { row.add(Document.COLUMN_SUMMARY, "? files"); } // Only publish dates reasonably after epoch long lastModified = zipEntry.getTime(); if (lastModified > 31536000000L) { row.add(Document.COLUMN_LAST_MODIFIED, lastModified); } } @Override public Cursor queryRoots(String[] projection) throws FileNotFoundException { final MatrixCursor result = new MatrixCursor(resolveRootProjection(projection)); synchronized (mRootsLock) { for (String rootId : mIdToPath.keySet()) { final RootInfo root = mIdToRoot.get(rootId); final File path = mIdToPath.get(rootId); final RowBuilder row = result.newRow(); row.add(Root.COLUMN_ROOT_ID, root.rootId); row.add(Root.COLUMN_FLAGS, root.flags); row.add(Root.COLUMN_TITLE, root.title); row.add(Root.COLUMN_DOCUMENT_ID, root.docId); row.add(Root.COLUMN_PATH, root.path); if (ROOT_ID_PRIMARY_EMULATED.equals(root.rootId) || root.rootId.startsWith(ROOT_ID_SECONDARY) || root.rootId.startsWith(ROOT_ID_PHONE)) { final File file = root.rootId.startsWith(ROOT_ID_PHONE) ? Environment.getRootDirectory() : path; row.add(Root.COLUMN_AVAILABLE_BYTES, file.getFreeSpace()); row.add(Root.COLUMN_TOTAL_BYTES, file.getTotalSpace()); } } } return result; } @Override public boolean isChildDocument(String parentDocId, String docId) { try { final File parent = getFileForDocId(parentDocId).getCanonicalFile(); final File doc = getFileForDocId(docId).getCanonicalFile(); return FileUtils.contains(parent, doc); } catch (IOException e) { throw new IllegalArgumentException( "Failed to determine if " + docId + " is child of " + parentDocId + ": " + e); } } @Override public String createDocument(String docId, String mimeType, String displayName) throws FileNotFoundException { displayName = FileUtils.buildValidFatFilename(displayName); final File parent = getFileForDocId(docId); if (!parent.isDirectory()) { throw new IllegalArgumentException("Parent document isn't a directory"); } final File file = FileUtils.buildUniqueFile(parent, mimeType, displayName); if (Document.MIME_TYPE_DIR.equals(mimeType)) { if (!file.mkdir()) { throw new IllegalStateException("Failed to mkdir " + file); } } else { try { if (!file.createNewFile()) { throw new IllegalStateException("Failed to touch " + file); } } catch (IOException e) { throw new IllegalStateException("Failed to touch " + file + ": " + e); } } return getDocIdForFile(file); } @Override public void deleteDocument(String docId) throws FileNotFoundException { final File file = getFileForDocId(docId); if (!FileUtils.deleteFile(file)) { throw new IllegalStateException("Failed to delete " + file); } } @Override public void moveDocument(String documentIdFrom, String documentIdTo, boolean deleteAfter) throws FileNotFoundException { final File fileFrom = getFileForDocId(documentIdFrom); final File fileTo = getFileForDocId(documentIdTo); if (!FileUtils.moveFile(fileFrom, fileTo, null)) { throw new IllegalStateException("Failed to copy " + fileFrom); } else { if (deleteAfter) { if (!FileUtils.deleteFile(fileFrom)) { throw new IllegalStateException("Failed to delete " + fileFrom); } else { FileUtils.updateMedia(getContext(), fileFrom.getPath()); } } } } @Override public String renameDocument(String parentDocumentId, String mimeType, String displayName) throws FileNotFoundException { // Since this provider treats renames as generating a completely new // docId, we're okay with letting the MIME type change. displayName = FileUtils.buildValidFatFilename(displayName); final File parent = getFileForDocId(parentDocumentId); File file; if (parent.isDirectory()) { file = new File(parent.getParentFile(), FileUtils.removeExtension(mimeType, displayName)); } else { displayName = FileUtils.removeExtension(mimeType, displayName); file = new File(parent.getParentFile(), FileUtils.addExtension(mimeType, displayName)); } if (parent.canWrite()) { parent.renameTo(file); } return getDocIdForFile(file); } @Override public String compressDocument(String parentDocumentId, ArrayList<String> documentIds) throws FileNotFoundException { final File fileFrom = getFileForDocId(parentDocumentId); ArrayList<File> files = Lists.newArrayList(); for (String documentId : documentIds) { files.add(getFileForDocId(documentId)); } if (!FileUtils.compressFile(fileFrom, files)) { throw new IllegalStateException("Failed to extract " + fileFrom); } return getDocIdForFile(fileFrom); } @Override public String uncompressDocument(String documentId) throws FileNotFoundException { final File fileFrom = getFileForDocId(documentId); if (!FileUtils.uncompress(fileFrom)) { throw new IllegalStateException("Failed to extract " + fileFrom); } return getDocIdForFile(fileFrom); } @Override public Cursor queryDocument(String documentId, String[] projection) throws FileNotFoundException { final MatrixCursor result = new MatrixCursor(resolveDocumentProjection(projection)); updateSettings(); includeFile(result, documentId, null); return result; } @Override public Cursor queryChildDocuments(String parentDocumentId, String[] projection, String sortOrder) throws FileNotFoundException { String mimeType = getDocumentType(parentDocumentId); final File parent = getFileForDocId(parentDocumentId); final MatrixCursor result = new DirectoryCursor(resolveDocumentProjection(projection), parentDocumentId, parent); updateSettings(); if (!MimePredicate.mimeMatches(MimePredicate.COMPRESSED_MIMES, mimeType)) { for (File file : parent.listFiles()) { includeFile(result, null, file); } } else { handleCompressedFile(result, parentDocumentId, parent); } return result; } @SuppressWarnings("resource") private void handleCompressedFile(MatrixCursor result, String parentDocumentId, File parent) { try { ZipInputStream zipInputStream = new ZipInputStream(new FileInputStream(parent.getPath())); ZipEntry zipEntry; while ((zipEntry = zipInputStream.getNextEntry()) != null) { includeZIPFile(result, null, zipEntry); } } catch (Exception e) { } } @Override public Cursor querySearchDocuments(String rootId, String query, String[] projection) throws FileNotFoundException { final MatrixCursor result = new MatrixCursor(resolveDocumentProjection(projection)); final File parent; synchronized (mRootsLock) { parent = mIdToPath.get(rootId); } /* final LinkedList<File> pending = new LinkedList<File>(); pending.add(parent); while (!pending.isEmpty() && result.getCount() < 24) { final File file = pending.removeFirst(); if (file.isDirectory()) { for (File child : file.listFiles()) { pending.add(child); } } if (file.getName().toLowerCase().contains(query)) { includeFile(result, null, file); } }*/ updateSettings(); for (File file : FileUtils.searchDirectory(parent.getPath(), query)) { includeFile(result, null, file); } return result; } @Override public String getDocumentType(String documentId) throws FileNotFoundException { final File file = getFileForDocId(documentId); return getTypeForFile(file); } @TargetApi(Build.VERSION_CODES.KITKAT) @Override public ParcelFileDescriptor openDocument(String documentId, String mode, CancellationSignal signal) throws FileNotFoundException { final File file = getFileForDocId(documentId); if (Utils.hasKitKat()) { final int pfdMode = ParcelFileDescriptor.parseMode(mode); if (pfdMode == ParcelFileDescriptor.MODE_READ_ONLY) { return ParcelFileDescriptor.open(file, pfdMode); } else { try { // When finished writing, kick off media scanner return ParcelFileDescriptor.open(file, pfdMode, mHandler, new ParcelFileDescriptor.OnCloseListener() { @Override public void onClose(IOException e) { FileUtils.updateMedia(getContext(), file.getPath()); } }); } catch (IOException e) { throw new FileNotFoundException("Failed to open for writing: " + e); } } } else { return ParcelFileDescriptor.open(file, ParcelFileDescriptor.MODE_READ_ONLY);//ParcelFileDescriptor.parseMode(mode)); } } @Override public AssetFileDescriptor openDocumentThumbnail(String documentId, Point sizeHint, CancellationSignal signal) throws FileNotFoundException { return openOrCreateDocumentThumbnail(documentId, sizeHint, signal); } public AssetFileDescriptor openOrCreateDocumentThumbnail(String docId, Point sizeHint, CancellationSignal signal) throws FileNotFoundException { // final ContentResolver resolver = getContext().getContentResolver(); final File file = getFileForDocId(docId); final String mimeType = getTypeForFile(file); final String typeOnly = mimeType.split("/")[0]; final long token = Binder.clearCallingIdentity(); try { if (MediaDocumentsProvider.TYPE_AUDIO.equals(typeOnly)) { final long id = getAlbumForPathCleared(file.getPath()); return openOrCreateAudioThumbnailCleared(id, signal); } else if (MediaDocumentsProvider.TYPE_IMAGE.equals(typeOnly)) { final long id = getImageForPathCleared(file.getPath()); return openOrCreateImageThumbnailCleared(id, signal); } else if (MediaDocumentsProvider.TYPE_VIDEO.equals(typeOnly)) { final long id = getVideoForPathCleared(file.getPath()); return openOrCreateVideoThumbnailCleared(id, signal); } else { return DocumentsContract.openImageThumbnail(file); } } finally { Binder.restoreCallingIdentity(token); } } private static String getTypeForFile(File file) { if (file.isDirectory()) { return Document.MIME_TYPE_DIR; } else { return getTypeForName(file.getName()); } } private static String getTypeForName(String name) { final int lastDot = name.lastIndexOf('.'); if (lastDot >= 0) { final String extension = name.substring(lastDot + 1).toLowerCase(); final String mime = MimeTypes.getMimeTypeFromExtension(extension); if (mime != null) { return mime; } } return "application/octet-stream"; } private void startObserving(File file, Uri notifyUri) { synchronized (mObservers) { DirectoryObserver observer = mObservers.get(file); if (observer == null) { observer = new DirectoryObserver(file, getContext().getContentResolver(), notifyUri); observer.startWatching(); mObservers.put(file, observer); } observer.mRefCount++; if (LOG_INOTIFY) Log.d(TAG, "after start: " + observer); } } private void stopObserving(File file) { synchronized (mObservers) { DirectoryObserver observer = mObservers.get(file); if (observer == null) return; observer.mRefCount--; if (observer.mRefCount == 0) { mObservers.remove(file); observer.stopWatching(); } if (LOG_INOTIFY) Log.d(TAG, "after stop: " + observer); } } private class DirectoryObserver extends FileObserver { private static final int NOTIFY_EVENTS = ATTRIB | CLOSE_WRITE | MOVED_FROM | MOVED_TO | CREATE | DELETE | DELETE_SELF | MOVE_SELF; private final File mFile; private final ContentResolver mResolver; private final Uri mNotifyUri; private int mRefCount = 0; public DirectoryObserver(File file, ContentResolver resolver, Uri notifyUri) { super(file.getAbsolutePath(), NOTIFY_EVENTS); mFile = file; mResolver = resolver; mNotifyUri = notifyUri; } @Override public void onEvent(int event, String path) { if ((event & NOTIFY_EVENTS) != 0) { if (LOG_INOTIFY) Log.d(TAG, "onEvent() " + event + " at " + path); //notify roots changed //mResolver.notifyChange(DocumentsContract.buildRootsUri(AUTHORITY), null, false); switch ((event & NOTIFY_EVENTS)) { case MOVED_FROM: case MOVED_TO: case CREATE: case DELETE: mResolver.notifyChange(mNotifyUri, null, false); FileUtils.updateMedia(getContext(), FileUtils.makeFilePath(mFile, path)); break; } } } @Override public String toString() { return "DirectoryObserver{file=" + mFile.getAbsolutePath() + ", ref=" + mRefCount + "}"; } } private class DirectoryCursor extends MatrixCursor { private final File mFile; public DirectoryCursor(String[] columnNames, String docId, File file) { super(columnNames); final Uri notifyUri = DocumentsContract.buildChildDocumentsUri(AUTHORITY, docId); setNotificationUri(getContext().getContentResolver(), notifyUri); mFile = file; startObserving(mFile, notifyUri); } @Override public void close() { super.close(); stopObserving(mFile); } } }