下面列出了android.content.res.AssetFileDescriptor#UNKNOWN_LENGTH 实例代码，或者点击链接到github查看源代码，也可以在右侧发表评论。
protected AssetFileDescriptor openVideoThumbnailCleared(long id, CancellationSignal signal)
throws FileNotFoundException {
final ContentResolver resolver = getContext().getContentResolver();
Cursor cursor = null;
try {
cursor = resolver.query(Video.Thumbnails.EXTERNAL_CONTENT_URI,
VideoThumbnailQuery.PROJECTION, Video.Thumbnails.VIDEO_ID + "=" + id, null,
null);
if (cursor.moveToFirst()) {
final String data = cursor.getString(VideoThumbnailQuery._DATA);
return new AssetFileDescriptor(ParcelFileDescriptor.open(
new File(data), ParcelFileDescriptor.MODE_READ_ONLY), 0,
AssetFileDescriptor.UNKNOWN_LENGTH);
}
} finally {
IoUtils.closeQuietly(cursor);
}
return null;
}
protected AssetFileDescriptor openVideoThumbnailCleared(long id, CancellationSignal signal)
throws FileNotFoundException {
final ContentResolver resolver = getContext().getContentResolver();
Cursor cursor = null;
try {
cursor = resolver.query(Video.Thumbnails.EXTERNAL_CONTENT_URI,
VideoThumbnailQuery.PROJECTION, Video.Thumbnails.VIDEO_ID + "=" + id, null,
null);
if (cursor.moveToFirst()) {
final String data = cursor.getString(VideoThumbnailQuery._DATA);
return new AssetFileDescriptor(ParcelFileDescriptor.open(
new File(data), ParcelFileDescriptor.MODE_READ_ONLY), 0,
AssetFileDescriptor.UNKNOWN_LENGTH);
}
} finally {
IoUtils.closeQuietly(cursor);
}
return null;
}
protected AssetFileDescriptor openVideoThumbnailCleared(long id, CancellationSignal signal)
throws FileNotFoundException {
final ContentResolver resolver = getContext().getContentResolver();
Cursor cursor = null;
try {
cursor = resolver.query(Video.Thumbnails.EXTERNAL_CONTENT_URI,
VideoThumbnailQuery.PROJECTION, Video.Thumbnails.VIDEO_ID + "=" + id, null,
null);
if (cursor.moveToFirst()) {
final String data = cursor.getString(VideoThumbnailQuery._DATA);
return new AssetFileDescriptor(ParcelFileDescriptor.open(
new File(data), ParcelFileDescriptor.MODE_READ_ONLY), 0,
AssetFileDescriptor.UNKNOWN_LENGTH);
}
} finally {
IoUtils.closeQuietly(cursor);
}
return null;
}
private AssetFileDescriptor fetchNonAssetFile(final Uri uri, final String fileName, final String identifier) {
try {
final File file = new File(contentPath + identifier, fileName);
return new AssetFileDescriptor(ParcelFileDescriptor.open(file, ParcelFileDescriptor.MODE_READ_ONLY), 0,
AssetFileDescriptor.UNKNOWN_LENGTH);
} catch (final IOException e) {
Log.e(Objects.requireNonNull(getContext()).getPackageName(),
"IOException when getting asset file, uri:" + uri, e);
return null;
}
}
@Override
public long open(DataSpec dataSpec) throws ContentDataSourceException {
try {
uri = dataSpec.uri;
transferInitializing(dataSpec);
assetFileDescriptor = resolver.openAssetFileDescriptor(uri, "r");
if (assetFileDescriptor == null) {
throw new FileNotFoundException("Could not open file descriptor for: " + uri);
}
inputStream = new FileInputStream(assetFileDescriptor.getFileDescriptor());
long assetStartOffset = assetFileDescriptor.getStartOffset();
long skipped = inputStream.skip(assetStartOffset + dataSpec.position) - assetStartOffset;
if (skipped != dataSpec.position) {
// We expect the skip to be satisfied in full. If it isn't then we're probably trying to
// skip beyond the end of the data.
throw new EOFException();
}
if (dataSpec.length != C.LENGTH_UNSET) {
bytesRemaining = dataSpec.length;
} else {
long assetFileDescriptorLength = assetFileDescriptor.getLength();
if (assetFileDescriptorLength == AssetFileDescriptor.UNKNOWN_LENGTH) {
// The asset must extend to the end of the file. If FileInputStream.getChannel().size()
// returns 0 then the remaining length cannot be determined.
FileChannel channel = inputStream.getChannel();
long channelSize = channel.size();
bytesRemaining = channelSize == 0 ? C.LENGTH_UNSET : channelSize - channel.position();
} else {
bytesRemaining = assetFileDescriptorLength - skipped;
}
}
} catch (IOException e) {
throw new ContentDataSourceException(e);
}
opened = true;
transferStarted(dataSpec);
return bytesRemaining;
}
@Override
public AssetFileDescriptor openDocumentThumbnail(String documentId, Point sizeHint,
CancellationSignal signal)
throws FileNotFoundException {
Log.v(TAG, "openDocumentThumbnail");
final File file = getFileForDocId(documentId);
final ParcelFileDescriptor pfd =
ParcelFileDescriptor.open(file, ParcelFileDescriptor.MODE_READ_ONLY);
return new AssetFileDescriptor(pfd, 0, AssetFileDescriptor.UNKNOWN_LENGTH);
}
@Override
public AssetFileDescriptor openDocumentThumbnail(String documentId, Point sizeHint, CancellationSignal signal) {
ensureServiceBound();
try {
return new AssetFileDescriptor(
mService.openThumbnail(documentId, sizeHint), 0, AssetFileDescriptor.UNKNOWN_LENGTH);
} catch (RemoteException e) {
return null;
}
}
@Override
public long open(DataSpec dataSpec) throws ContentDataSourceException {
try {
uri = dataSpec.uri;
transferInitializing(dataSpec);
assetFileDescriptor = resolver.openAssetFileDescriptor(uri, "r");
if (assetFileDescriptor == null) {
throw new FileNotFoundException("Could not open file descriptor for: " + uri);
}
inputStream = new FileInputStream(assetFileDescriptor.getFileDescriptor());
long assetStartOffset = assetFileDescriptor.getStartOffset();
long skipped = inputStream.skip(assetStartOffset + dataSpec.position) - assetStartOffset;
if (skipped != dataSpec.position) {
// We expect the skip to be satisfied in full. If it isn't then we're probably trying to
// skip beyond the end of the data.
throw new EOFException();
}
if (dataSpec.length != C.LENGTH_UNSET) {
bytesRemaining = dataSpec.length;
} else {
long assetFileDescriptorLength = assetFileDescriptor.getLength();
if (assetFileDescriptorLength == AssetFileDescriptor.UNKNOWN_LENGTH) {
// The asset must extend to the end of the file. If FileInputStream.getChannel().size()
// returns 0 then the remaining length cannot be determined.
FileChannel channel = inputStream.getChannel();
long channelSize = channel.size();
bytesRemaining = channelSize == 0 ? C.LENGTH_UNSET : channelSize - channel.position();
} else {
bytesRemaining = assetFileDescriptorLength - skipped;
}
}
} catch (IOException e) {
throw new ContentDataSourceException(e);
}
opened = true;
transferStarted(dataSpec);
return bytesRemaining;
}
@Override
public AssetFileDescriptor openDocumentThumbnail(
String docId, Point sizeHint, CancellationSignal signal) throws FileNotFoundException {
// TODO: extend ExifInterface to support fds
final ParcelFileDescriptor pfd = openDocument(docId, "r", signal);
return new AssetFileDescriptor(pfd, 0, AssetFileDescriptor.UNKNOWN_LENGTH);
}
@Override
public AssetFileDescriptor openDocumentThumbnail(
String docId, Point sizeHint, CancellationSignal signal) throws FileNotFoundException {
// TODO: extend ExifInterface to support fds
final ParcelFileDescriptor pfd = openDocument(docId, "r", signal);
return new AssetFileDescriptor(pfd, 0, AssetFileDescriptor.UNKNOWN_LENGTH);
}
@Override
public AssetFileDescriptor openDocumentThumbnail(
String docId, Point sizeHint, CancellationSignal signal) throws FileNotFoundException {
// TODO: extend ExifInterface to support fds
final ParcelFileDescriptor pfd = openDocument(docId, "r", signal);
return new AssetFileDescriptor(pfd, 0, AssetFileDescriptor.UNKNOWN_LENGTH);
}
@Override
public long open(DataSpec dataSpec) throws ContentDataSourceException {
try {
uri = dataSpec.uri;
transferInitializing(dataSpec);
assetFileDescriptor = resolver.openAssetFileDescriptor(uri, "r");
if (assetFileDescriptor == null) {
throw new FileNotFoundException("Could not open file descriptor for: " + uri);
}
inputStream = new FileInputStream(assetFileDescriptor.getFileDescriptor());
long assetStartOffset = assetFileDescriptor.getStartOffset();
long skipped = inputStream.skip(assetStartOffset + dataSpec.position) - assetStartOffset;
if (skipped != dataSpec.position) {
// We expect the skip to be satisfied in full. If it isn't then we're probably trying to
// skip beyond the end of the data.
throw new EOFException();
}
if (dataSpec.length != C.LENGTH_UNSET) {
bytesRemaining = dataSpec.length;
} else {
long assetFileDescriptorLength = assetFileDescriptor.getLength();
if (assetFileDescriptorLength == AssetFileDescriptor.UNKNOWN_LENGTH) {
// The asset must extend to the end of the file. If FileInputStream.getChannel().size()
// returns 0 then the remaining length cannot be determined.
FileChannel channel = inputStream.getChannel();
long channelSize = channel.size();
bytesRemaining = channelSize == 0 ? C.LENGTH_UNSET : channelSize - channel.position();
} else {
bytesRemaining = assetFileDescriptorLength - skipped;
}
}
} catch (IOException e) {
throw new ContentDataSourceException(e);
}
opened = true;
transferStarted(dataSpec);
return bytesRemaining;
}
@Override
public AssetFileDescriptor openDocumentThumbnail(String documentId, Point sizeHint,
CancellationSignal signal)
throws FileNotFoundException {
Log.v(TAG, "openDocumentThumbnail");
final File file = getFileForDocId(documentId);
final ParcelFileDescriptor pfd =
ParcelFileDescriptor.open(file, ParcelFileDescriptor.MODE_READ_ONLY);
return new AssetFileDescriptor(pfd, 0, AssetFileDescriptor.UNKNOWN_LENGTH);
}
@Override
public AssetFileDescriptor openAssetFile(Uri uri, String mode) throws FileNotFoundException {
// Try to open an asset with the given name.
try {
InputStream is = getContext().getAssets().open(uri.getPath());
// Start a new thread that pipes the stream data back to the caller.
return new AssetFileDescriptor(
openPipeHelper(uri, null, null, is, this), 0,
AssetFileDescriptor.UNKNOWN_LENGTH);
} catch (IOException e) {
FileNotFoundException fnf = new FileNotFoundException("Unable to open " + uri);
throw fnf;
}
}
@Override
public long open(DataSpec dataSpec) throws ContentDataSourceException {
try {
uri = dataSpec.uri;
transferInitializing(dataSpec);
assetFileDescriptor = resolver.openAssetFileDescriptor(uri, "r");
if (assetFileDescriptor == null) {
throw new FileNotFoundException("Could not open file descriptor for: " + uri);
}
inputStream = new FileInputStream(assetFileDescriptor.getFileDescriptor());
long assetStartOffset = assetFileDescriptor.getStartOffset();
long skipped = inputStream.skip(assetStartOffset + dataSpec.position) - assetStartOffset;
if (skipped != dataSpec.position) {
// We expect the skip to be satisfied in full. If it isn't then we're probably trying to
// skip beyond the end of the data.
throw new EOFException();
}
if (dataSpec.length != C.LENGTH_UNSET) {
bytesRemaining = dataSpec.length;
} else {
long assetFileDescriptorLength = assetFileDescriptor.getLength();
if (assetFileDescriptorLength == AssetFileDescriptor.UNKNOWN_LENGTH) {
// The asset must extend to the end of the file. If FileInputStream.getChannel().size()
// returns 0 then the remaining length cannot be determined.
FileChannel channel = inputStream.getChannel();
long channelSize = channel.size();
bytesRemaining = channelSize == 0 ? C.LENGTH_UNSET : channelSize - channel.position();
} else {
bytesRemaining = assetFileDescriptorLength - skipped;
}
}
} catch (IOException e) {
throw new ContentDataSourceException(e);
}
opened = true;
transferStarted(dataSpec);
return bytesRemaining;
}
@Override
public long open(DataSpec dataSpec) throws ContentDataSourceException {
try {
Uri uri = dataSpec.uri;
this.uri = uri;
transferInitializing(dataSpec);
AssetFileDescriptor assetFileDescriptor = resolver.openAssetFileDescriptor(uri, "r");
this.assetFileDescriptor = assetFileDescriptor;
if (assetFileDescriptor == null) {
throw new FileNotFoundException("Could not open file descriptor for: " + uri);
}
FileInputStream inputStream = new FileInputStream(assetFileDescriptor.getFileDescriptor());
this.inputStream = inputStream;
long assetStartOffset = assetFileDescriptor.getStartOffset();
long skipped = inputStream.skip(assetStartOffset + dataSpec.position) - assetStartOffset;
if (skipped != dataSpec.position) {
// We expect the skip to be satisfied in full. If it isn't then we're probably trying to
// skip beyond the end of the data.
throw new EOFException();
}
if (dataSpec.length != C.LENGTH_UNSET) {
bytesRemaining = dataSpec.length;
} else {
long assetFileDescriptorLength = assetFileDescriptor.getLength();
if (assetFileDescriptorLength == AssetFileDescriptor.UNKNOWN_LENGTH) {
// The asset must extend to the end of the file. If FileInputStream.getChannel().size()
// returns 0 then the remaining length cannot be determined.
FileChannel channel = inputStream.getChannel();
long channelSize = channel.size();
bytesRemaining = channelSize == 0 ? C.LENGTH_UNSET : channelSize - channel.position();
} else {
bytesRemaining = assetFileDescriptorLength - skipped;
}
}
} catch (IOException e) {
throw new ContentDataSourceException(e);
}
opened = true;
transferStarted(dataSpec);
return bytesRemaining;
}