下面列出了android.content.res.AssetFileDescriptor#createInputStream() 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。
@TargetApi(Build.VERSION_CODES.ECLAIR)
private void queryContactPhoto() {
Uri uri = Uri.withAppendedPath(ContactsContract.AUTHORITY_URI, photoUri);
try {
AssetFileDescriptor fd = registrar.context().getContentResolver().openAssetFileDescriptor(
uri, "r");
if (fd != null) {
InputStream stream = fd.createInputStream();
byte[] bytes = getBytesFromInputStream(stream);
stream.close();
result.success(bytes);
}
} catch (IOException e) {
e.printStackTrace();
}
}
private static InputStream getInputStreamForVirtualFile(Context context, Uri uri)
throws IOException {
ContentResolver resolver = context.getContentResolver();
String[] openableMimeTypes = resolver.getStreamTypes(uri, "*/*");
if (openableMimeTypes == null ||
openableMimeTypes.length < 1) {
throw new FileNotFoundException();
}
AssetFileDescriptor assetFileDescriptor = resolver.openAssetFileDescriptor(uri, openableMimeTypes[0], null);
if (assetFileDescriptor == null) {
throw new IOException("open virtual file failed");
}
return assetFileDescriptor.createInputStream();
}
public static FileInfo getContactAsVCardFile(Context context, Uri uri) {
AssetFileDescriptor fd;
try {
fd = context.getContentResolver().openAssetFileDescriptor(uri, "r");
java.io.FileInputStream in = fd.createInputStream();
byte[] buf = new byte[(int) fd.getDeclaredLength()];
in.read(buf);
in.close();
String vCardText = new String(buf);
Log.d("Vcard", vCardText);
List<String> pathSegments = uri.getPathSegments();
String targetPath = "/" + pathSegments.get(pathSegments.size() - 1) + ".vcf";
SecureMediaStore.copyToVfs(buf, targetPath);
FileInfo info = new FileInfo();
info.stream = new info.guardianproject.iocipher.FileInputStream(SecureMediaStore.vfsUri(targetPath).getPath());
info.type = "text/vcard";
return info;
} catch (Exception e) {
e.printStackTrace();
}
return null;
}
private byte[] loadBytes() {
try {
AssetFileDescriptor assetFileDescriptor = getAssets().openFd("lite_template/card.wasm");
long len = assetFileDescriptor.getDeclaredLength();
ByteBuffer buf = ByteBuffer.allocate((int) len);
InputStream json = assetFileDescriptor.createInputStream();
json.read(buf.array());
json.close();
return buf.array();
} catch (IOException e) {
e.printStackTrace();
}
return null;
}
/**
* Open a stream on to the content associated with a content URI. If there
* is no data associated with the URI, FileNotFoundException is thrown.
*
* <h5>Accepts the following URI schemes:</h5>
* <ul>
* <li>content ({@link #SCHEME_CONTENT})</li>
* <li>android.resource ({@link #SCHEME_ANDROID_RESOURCE})</li>
* <li>file ({@link #SCHEME_FILE})</li>
* </ul>
*
* <p>See {@link #openAssetFileDescriptor(Uri, String)} for more information
* on these schemes.
*
* @param uri The desired URI.
* @return InputStream
* @throws FileNotFoundException if the provided URI could not be opened.
* @see #openAssetFileDescriptor(Uri, String)
*/
public final @Nullable InputStream openInputStream(@NonNull Uri uri)
throws FileNotFoundException {
Preconditions.checkNotNull(uri, "uri");
String scheme = uri.getScheme();
if (SCHEME_ANDROID_RESOURCE.equals(scheme)) {
// Note: left here to avoid breaking compatibility. May be removed
// with sufficient testing.
OpenResourceIdResult r = getResourceId(uri);
try {
InputStream stream = r.r.openRawResource(r.id);
return stream;
} catch (Resources.NotFoundException ex) {
throw new FileNotFoundException("Resource does not exist: " + uri);
}
} else if (SCHEME_FILE.equals(scheme)) {
// Note: left here to avoid breaking compatibility. May be removed
// with sufficient testing.
return new FileInputStream(uri.getPath());
} else {
AssetFileDescriptor fd = openAssetFileDescriptor(uri, "r", null);
try {
return fd != null ? fd.createInputStream() : null;
} catch (IOException e) {
throw new FileNotFoundException("Unable to create stream");
}
}
}
/**
* Open a stream on to the content associated with a content URI. If there
* is no data associated with the URI, FileNotFoundException is thrown.
*
* <h5>Accepts the following URI schemes:</h5>
* <ul>
* <li>content ({@link #SCHEME_CONTENT})</li>
* <li>android.resource ({@link #SCHEME_ANDROID_RESOURCE})</li>
* <li>file ({@link #SCHEME_FILE})</li>
* </ul>
*
* <p>See {@link #openAssetFileDescriptor(Uri, String)} for more information
* on these schemes.
*
* @param uri The desired URI.
* @return InputStream
* @throws FileNotFoundException if the provided URI could not be opened.
* @see #openAssetFileDescriptor(Uri, String)
*/
public final @Nullable InputStream openInputStream(@NonNull Uri uri)
throws FileNotFoundException {
Preconditions.checkNotNull(uri, "uri");
String scheme = uri.getScheme();
if (SCHEME_ANDROID_RESOURCE.equals(scheme)) {
// Note: left here to avoid breaking compatibility. May be removed
// with sufficient testing.
OpenResourceIdResult r = getResourceId(uri);
try {
InputStream stream = r.r.openRawResource(r.id);
return stream;
} catch (Resources.NotFoundException ex) {
throw new FileNotFoundException("Resource does not exist: " + uri);
}
} else if (SCHEME_FILE.equals(scheme)) {
// Note: left here to avoid breaking compatibility. May be removed
// with sufficient testing.
return new FileInputStream(uri.getPath());
} else {
AssetFileDescriptor fd = openAssetFileDescriptor(uri, "r", null);
try {
return fd != null ? fd.createInputStream() : null;
} catch (IOException e) {
throw new FileNotFoundException("Unable to create stream");
}
}
}
/**
* Open a stream on to the content associated with a content URI. If there
* is no data associated with the URI, FileNotFoundException is thrown.
*
* <h5>Accepts the following URI schemes:</h5>
* <ul>
* <li>content ({@link #SCHEME_CONTENT})</li>
* <li>android.resource ({@link #SCHEME_ANDROID_RESOURCE})</li>
* <li>file ({@link #SCHEME_FILE})</li>
* </ul>
*
* <p>See {@link #openAssetFileDescriptor(Uri, String)} for more information
* on these schemes.
*
* @param uri The desired URI.
* @return InputStream
* @throws FileNotFoundException if the provided URI could not be opened.
* @see #openAssetFileDescriptor(Uri, String)
*/
public final @Nullable InputStream openInputStream(@NonNull Uri uri)
throws FileNotFoundException {
Preconditions.checkNotNull(uri, "uri");
String scheme = uri.getScheme();
if (SCHEME_ANDROID_RESOURCE.equals(scheme)) {
// Note: left here to avoid breaking compatibility. May be removed
// with sufficient testing.
OpenResourceIdResult r = getResourceId(uri);
try {
InputStream stream = r.r.openRawResource(r.id);
return stream;
} catch (Resources.NotFoundException ex) {
throw new FileNotFoundException("Resource does not exist: " + uri);
}
} else if (SCHEME_FILE.equals(scheme)) {
// Note: left here to avoid breaking compatibility. May be removed
// with sufficient testing.
return new FileInputStream(uri.getPath());
} else {
AssetFileDescriptor fd = openAssetFileDescriptor(uri, "r", null);
try {
return fd != null ? fd.createInputStream() : null;
} catch (IOException e) {
throw new FileNotFoundException("Unable to create stream");
}
}
}
public static void copy(ContentResolver resolver, Uri source, Uri dest, OnCopyListener listener) throws IOException {
FileInputStream in = null;
OutputStream out = null;
try{
AssetFileDescriptor fd = resolver.openAssetFileDescriptor(source, "r");
in = fd != null ? fd.createInputStream() : null;
if (in == null){
throw new IOException("open the src file failed");
}
long total = fd.getLength();
long sum = 0;
out = resolver.openOutputStream(dest);
if (out == null) {
throw new IOException("open the dest file failed");
}
// Transfer bytes from in to out
byte[] buf = new byte[1024 * 4];
int len;
Thread thread = Thread.currentThread();
while ((len = in.read(buf)) > 0) {
if (thread.isInterrupted()) {
break;
}
sum += len;
out.write(buf, 0, len);
if (listener != null) {
listener.inProgress(sum * 1.0f / total);
}
}
}finally {
IOUtil.closeQuiet(in);
IOUtil.closeQuiet(out);
}
}
/**
* Open a stream to the content associated with a URI.
*
* <p>
* If the provided URI is not a {@code file://} URI, {@link ContentResolver#openInputStream(Uri)} is used to open a
* stream. If it is a {@code file://}, this method makes sure the file isn't owned by this app.
* </p>
*
* @param uri
* The URI pointing to the content to access.
*
* @return {@code InputStream} to access the content.
*
* @throws FileNotFoundException
* If the provided URI could not be opened or if it points to a file owned by this app.
*/
@Nullable
public InputStream openInputStream(@NotNull Uri uri) throws FileNotFoundException {
//noinspection ConstantConditions
if (uri == null) {
throw new NullPointerException("Argument 'uri' must not be null");
}
String scheme = uri.getScheme();
if (ContentResolver.SCHEME_CONTENT.equals(scheme)) {
String authority = uri.getAuthority();
if (disallowedProviders.isDisallowed(authority)) {
throw new FileNotFoundException("content URI is owned by the application itself. " +
"Content provider is not explicitly allowed: " + authority);
}
}
if (!ContentResolver.SCHEME_FILE.equals(scheme)) {
return contentResolver.openInputStream(uri);
}
File file = new File(uri.getPath());
ParcelFileDescriptor parcelFileDescriptor = ParcelFileDescriptor.open(file, ParcelFileDescriptor.MODE_READ_ONLY);
FileDescriptor fileDescriptor = parcelFileDescriptor.getFileDescriptor();
int fileUid = getFileUidOrThrow(fileDescriptor);
if (fileUid == android.os.Process.myUid()) {
throw new FileNotFoundException("File is owned by the application itself");
}
AssetFileDescriptor fd = new AssetFileDescriptor(parcelFileDescriptor, 0, -1);
try {
return fd.createInputStream();
} catch (IOException e) {
throw new FileNotFoundException("Unable to create stream");
}
}
@Override
public boolean installCaCertificate(AssetFileDescriptor afd) {
try (FileInputStream fis = afd.createInputStream()) {
return Util.installCaCertificate(fis, mDpm, DeviceAdminReceiver.getComponentName(
mContext));
} catch (IOException e) {
Log.e(TAG, "Unable to install a certificate", e);
return false;
}
}
@Override
protected EncodedImage getEncodedImage(ImageRequest imageRequest) throws IOException {
Uri uri = imageRequest.getSourceUri();
if (UriUtil.isLocalContactUri(uri)) {
final InputStream inputStream;
if (uri.toString().endsWith("/photo")) {
inputStream = mContentResolver.openInputStream(uri);
} else if (uri.toString().endsWith("/display_photo")) {
try {
AssetFileDescriptor fd = mContentResolver.openAssetFileDescriptor(uri, "r");
inputStream = fd.createInputStream();
} catch (IOException e) {
throw new IOException("Contact photo does not exist: " + uri);
}
} else {
inputStream = ContactsContract.Contacts.openContactPhotoInputStream(mContentResolver, uri);
if (inputStream == null) {
throw new IOException("Contact photo does not exist: " + uri);
}
}
// If a Contact URI is provided, use the special helper to open that contact's photo.
return getEncodedImage(inputStream, EncodedImage.UNKNOWN_STREAM_SIZE);
}
if (UriUtil.isLocalCameraUri(uri)) {
EncodedImage cameraImage = getCameraImage(uri);
if (cameraImage != null) {
return cameraImage;
}
}
return getEncodedImage(mContentResolver.openInputStream(uri), EncodedImage.UNKNOWN_STREAM_SIZE);
}
/**
* Get the InputStream object of the contact photo with given contact ID.
*
* @param context Context object of the caller.
* @param contactId Contact ID.
* @return InputStream object of the contact photo.
*/
public static InputStream openDisplayPhoto(Context context, long contactId) {
Uri contactUri =
ContentUris.withAppendedId(ContactsContract.Contacts.CONTENT_URI, contactId);
Uri displayPhotoUri =
Uri.withAppendedPath(contactUri, ContactsContract.Contacts.Photo.DISPLAY_PHOTO);
try {
AssetFileDescriptor fd =
context.getContentResolver().openAssetFileDescriptor(displayPhotoUri, "r");
return fd.createInputStream();
} catch (IOException e) {
return null;
}
}
public void readFile(Uri inputFile)
throws java.io.FileNotFoundException,
java.io.IOException {
super.readFile(inputFile);
mNumFrames = 0;
mMaxFrames = 64; // This will grow as needed
mFrameGains = new int[mMaxFrames];
mMinGain = 1000000000;
mMaxGain = 0;
mBitRate = 10;
mOffset = 0;
InputStream stream = null;
AssetFileDescriptor file;
file = App.getInstance().getContentResolver().openAssetFileDescriptor(inputFile, "r");
if(file == null) throw new NullPointerException("File is null");
stream = file.createInputStream();
if(stream == null) throw new NullPointerException("Input stream is null");
else Log.d("audioSeekbar", "ReadFile: input stream is not null");
// No need to handle filesizes larger than can fit in a 32-bit int
mFileSize = (int) file.getLength();
if (mFileSize < 128) {
throw new java.io.IOException("File too small to parse");
}
byte[] header = new byte[12];
stream.read(header, 0, 6);
mOffset += 6;
if (header[0] == '#' &&
header[1] == '!' &&
header[2] == 'A' &&
header[3] == 'M' &&
header[4] == 'R' &&
header[5] == '\n') {
parseAMR(stream, mFileSize - 6);
}
stream.read(header, 6, 6);
mOffset += 6;
if (header[4] == 'f' &&
header[5] == 't' &&
header[6] == 'y' &&
header[7] == 'p' &&
header[8] == '3' &&
header[9] == 'g' &&
header[10] == 'p' &&
header[11] == '4') {
int boxLen =
((0xff & header[0]) << 24) |
((0xff & header[1]) << 16) |
((0xff & header[2]) << 8) |
((0xff & header[3]));
if (boxLen >= 4 && boxLen <= mFileSize - 8) {
stream.skip(boxLen - 12);
mOffset += boxLen - 12;
}
parse3gpp(stream, mFileSize - boxLen);
}
}
public void readFile(Uri inputFile) throws java.io.IOException {
super.readFile(inputFile);
InputStream stream = null;
AssetFileDescriptor file;
file = App.getInstance().getContentResolver().openAssetFileDescriptor(inputFile, "r");
if(file == null) throw new NullPointerException("File is null");
stream = file.createInputStream();
if(stream == null) throw new NullPointerException("Input stream is null");
else Log.d("audioSeekbar", "ReadFile: input stream is not null");
// No need to handle filesizes larger than can fit in a 32-bit int
mFileSize = (int) file.getLength();
if (mFileSize < 128) {
throw new java.io.IOException("File too small to parse");
}
try {
WavFileDescriptor wavFile = WavFileDescriptor.openWavFile(file);
mNumFrames = (int) (wavFile.getNumFrames() / getSamplesPerFrame());
mFrameGains = new int[mNumFrames];
mSampleRate = (int) wavFile.getSampleRate();
mChannels = wavFile.getNumChannels();
int gain, value;
int[] buffer = new int[getSamplesPerFrame()];
for (int i = 0; i < mNumFrames; i++) {
gain = -1;
wavFile.readFrames(buffer, getSamplesPerFrame());
for (int j = 0; j < getSamplesPerFrame(); j++) {
value = buffer[j];
if (gain < value) {
gain = value;
}
}
mFrameGains[i] = (int) Math.sqrt(gain);
if (mProgressListener != null) {
boolean keepGoing = mProgressListener.reportProgress(i * 1.0 / mFrameGains.length);
if (!keepGoing) {
break;
}
}
}
if (wavFile != null) {
wavFile.close();
}
} catch (WavFileException e) {
Log.e(TAG, "Exception while reading wav file", e);
}
}
public void readFile(Uri inputFile)
throws java.io.FileNotFoundException,
java.io.IOException {
super.readFile(inputFile);
mChannels = 0;
mSampleRate = 0;
mBitrate = 0;
mSamplesPerFrame = 0;
mNumFrames = 0;
mMinGain = 255;
mMaxGain = 0;
mOffset = 0;
mMdatOffset = -1;
mMdatLength = -1;
mAtomMap = new HashMap<Integer, Atom>();
InputStream stream = null;
AssetFileDescriptor file;
file = App.getInstance().getContentResolver().openAssetFileDescriptor(inputFile, "r");
if(file == null) throw new NullPointerException("File is null");
// Read the first 8 bytes
stream = file.createInputStream();
if(stream == null) throw new NullPointerException("Input stream is null");
else Log.d("audioSeekbar", "ReadFile: input stream is not null");
// No need to handle filesizes larger than can fit in a 32-bit int
mFileSize = (int) file.getLength();
if (mFileSize < 128) {
throw new java.io.IOException("File too small to parse");
}
byte[] header = new byte[8];
stream.read(header, 0, 8);
if (header[0] == 0 &&
header[4] == 'f' &&
header[5] == 't' &&
header[6] == 'y' &&
header[7] == 'p') {
// Create a new stream, reset to the beginning of the file
stream = file.createInputStream();
parseMp4(stream, mFileSize);
} else {
throw new java.io.IOException("Unknown file format");
}
if (mMdatOffset > 0 && mMdatLength > 0) {
stream = file.createInputStream();
stream.skip(mMdatOffset);
mOffset = mMdatOffset;
parseMdat(stream, mMdatLength);
} else {
throw new java.io.IOException("Didn't find mdat");
}
boolean bad = false;
for (int requiredAtomType : kRequiredAtoms) {
if (!mAtomMap.containsKey(requiredAtomType)) {
System.out.println("Missing atom: " +
atomToString(requiredAtomType));
bad = true;
}
}
if (bad) {
throw new java.io.IOException("Could not parse MP4 file");
}
}