Develop Reference

Change album art using jaudiotagger

I'm trying to change the album art of an audio file using jaudiotagger but it is not working. There are a lot of question regarding this topic but none of them fulfilled my requirements. Other fields such as artist,audio name, album etc are updated successfully but the album artwork remains the same.
The code I'm using to change the artwork:
public void changeAlbumArt(Uri data) {
Artwork cover = null;
try {
AudioFile f = null;
try {
f = AudioFileIO.read(new File(storageUtil.loadAudio().get(storageUtil.loadAudioIndex()).getData()));
} catch (CannotReadException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
} catch (TagException e) {
e.printStackTrace();
} catch (ReadOnlyFileException e) {
e.printStackTrace();
} catch (InvalidAudioFrameException e) {
e.printStackTrace();
}
Tag tag = null;
if (f != null) {
tag = f.getTag();
}
try {
if(tag!=null) {
cover = ArtworkFactory.createArtworkFromFile(new File(data.getPath()));
tag.deleteArtworkField();
tag.setField(cover);
}
} catch (FieldDataInvalidException e) {
e.printStackTrace();
}
try {
if (f != null) {
f.commit();
}
} catch (CannotWriteException e) {
e.printStackTrace();
}
} catch (Exception e) {
e.printStackTrace();
}
File file = new File(storageUtil.loadAudio().get(storageUtil.loadAudioIndex()).getData());
Uri uri = Uri.fromFile(file);
Intent scanFileIntent = new Intent(
Intent.ACTION_MEDIA_SCANNER_SCAN_FILE, uri);
sendBroadcast(scanFileIntent);
}

I had this working at one point but have reverted back to jid3 as jaudiotagger required some io files which were not available in android.
In addition, for android Gingerbread+ to write to external storage requires the SAF framework. I have managed to modify the jid3 library so it works but only for mp3.
for mp3 files:
public String setMp3AlbumArt(File SourceFile, byte[] bytes)
throws Exception {
String error = null;
try {
MP3File musicFile = (MP3File) AudioFileIO.read(SourceFile);
AbstractID3v2Tag tag = musicFile.getID3v2Tag();
if (tag != null) {
Artwork artwork = null;
try {
artwork = ArtworkFactory.createArtworkFromFile(SourceFile);
} catch (IOException e) {
e.printStackTrace();
error = e.getMessage();
}
if (artwork != null) {
artwork.setBinaryData(bytes);
tag.deleteArtworkField();
tag.setField(artwork);
musicFile.setTag(tag);
musicFile.commit();
} else {
artwork.setBinaryData(bytes);
tag.addField(artwork);
tag.setField(artwork);
musicFile.setTag(tag);
musicFile.commit();
}
}
} catch (CannotReadException | IOException | TagException
| ReadOnlyFileException | InvalidAudioFrameException e) {
error = e.getMessage();
}
return error;
}

How to save an application's data?

I have written a Web View app, which logs you into 12 different sites (sign in) which works pretty fine. However, i am trying to figure out a way to backup my web view's data (so that all the login credentials are saved) to SD card. the only way i have found is to copy the root/data/data/com.example/your app folder.
How do i copy this folder somewhere to my SD card using root command on the click of a button?
this is how i access and delete the data folder
private void clear() {
String cmd = "pm clear com.wagtailapp";
ProcessBuilder pb = new ProcessBuilder().redirectErrorStream(true)
.command("su");
Process p = null;
try {
p = pb.start();
} catch (IOException e) {
e.printStackTrace();
}
StreamReader stdoutReader = new StreamReader(p.getInputStream(),
CHARSET_NAME);
stdoutReader.start();
out = p.getOutputStream();
try {
out.write((cmd + "\n").getBytes(CHARSET_NAME));
} catch (UnsupportedEncodingException e1) {
e1.printStackTrace();
} catch (IOException e1) {
e1.printStackTrace();
}
try {
out.write(("exit" + "\n").getBytes(CHARSET_NAME));
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
try {
out.flush();
} catch (IOException e) {
e.printStackTrace();
}
try {
p.waitFor();
} catch (InterruptedException e) {
e.printStackTrace();
}
String result = stdoutReader.getResult();
}
}
streamreader.java
class StreamReader extends Thread {
private InputStream is;
private StringBuffer mBuffer;
private String mCharset;
private CountDownLatch mCountDownLatch;
StreamReader(InputStream is, String charset) {
this.is = is;
mCharset = charset;
mBuffer = new StringBuffer("");
mCountDownLatch = new CountDownLatch(1);
}
String getResult() {
try {
mCountDownLatch.await();
} catch (InterruptedException e) {
e.printStackTrace();
}
return mBuffer.toString();
}
#Override
public void run() {
InputStreamReader isr = null;
try {
isr = new InputStreamReader(is, mCharset);
int c = -1;
while ((c = isr.read()) != -1) {
mBuffer.append((char) c);
}
} catch (IOException e) {
e.printStackTrace();
} finally {
try {
if (isr != null)
isr.close();
} catch (IOException e) {
e.printStackTrace();
}
mCountDownLatch.countDown();
}
}
}

Open a file audio in R.Raw

I have to open a file that in the /res/raw/ folder, but it seems that android, doesn't recognize the path.
Here is my code:
public static void openRec()
{
//this is the wav file that I have to analyze
File file = new File("/res/raw/chirp.wav");
try {
FileInputStream in = new FileInputStream(file);
chirp = new byte[(int) file.length()];
in.read(chirp);
Log.d("xxx", "" + chirp.length);
in.close();
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
}
EDIT:
I have another method openRec in which, the path is passed as argument:
public static void openRec(String path) {
File file = new File(path);
try {
FileInputStream in = new FileInputStream(file);
recording = new byte[(int) file.length()];
in.read(recording);
Log.d("xxx", "" + recording.length);
in.close();
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
}
I would a method that do the same thing but with the ffile in /res/raw. How do I that?

Use in this manner
public static void openRec()
{
//this is the wav file that I have to analyze
try {
InputStream in = getResources().openRawResource(R.raw.chirp);
chirp = new byte[(int) file.length()];
in.read(chirp);
Log.d("xxx", "" + chirp.length);
in.close();
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
}

Storing a file to internal storage and reading it

What I am trying to do is store a JSON file as a string in internal storage to access it later. The reasoning behind this is to not have to access the server on every request, as this data is constant. Once it is stored once, it doesn't have to be retrieved again unless there is some sort of update. File storage isn't something I've done before, and I was hoping someone could give me a hand. My current code is throwing a null pointer exception at this line:
File file = new File(getFilesDir(), fileName);
My code:
protected String doInBackground(String[] runeId) {
String url = "https://prod.api.pvp.net/api/lol/static-data/" + region + "/v1.2/rune/" + runeId[0] + "?api_key=" + api_key;
JSONParser jsonParser = new JSONParser();
JSONObject runeInfo = jsonParser.getJSONFromUrl(url);
String jsonString = runeInfo.toString();
String fileName = "runeInfo";
File file = new File(getFilesDir(), fileName);
String readJson = null;
if(!runesCached) {
Log.d("Cache", "Caching File");
try {
FileOutputStream os = new FileOutputStream(file);
os.write(jsonString.getBytes());
os.close();
Log.d("Cache", "Cache Complete");
runesCached = true;
} catch (FileNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
String name = null;
try {
FileInputStream fis;
File storedRuneInfo = new File(getFilesDir(), fileName);
fis = new FileInputStream(storedRuneInfo);
fis.read(readJson.getBytes());
JSONObject storedJson = new JSONObject(readJson);
try {
name = storedJson.getString("name");
} catch (JSONException e) {
e.printStackTrace();
}
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (StreamCorruptedException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
} catch (JSONException e) {
e.printStackTrace();
}
return name;
}
}

Try this, instead:
File file = new File(getFilesDir().toString(), fileName);
getFilesDir() returns a File, not a String, which the File class constructor takes as a parameter.
getFilesDir()toString() should return something like /data/data/com.your.app/
EDIT:
This gives the same error. How about:
try {
FileWriter fstream;
BufferedWriter out;
fstream = new FileWriter(getFilesDir() + "/" + "filename");
out = new BufferedWriter(fstream);
out.write(jsonString.getBytes());
out.close();
} catch (Exception e){}

read/write an object to file

here is the code :
my mission is to serialize an my object(Person) , save it in a file in android(privately), read the file later,(i will get a byte array), and deserialize the byta array.
public void setup()
{
byte[] data = SerializationUtils.serialize(f);
WriteByteToFile(data,filename);
}
Person p =null ;
public void draw()
{
File te = new File(filename);
FileInputStream fin = null;
try {
fin=new FileInputStream(te);
byte filecon[]=new byte[(int)te.length()];
fin.read(filecon);
String s = new String(filecon);
System.out.println("File content: " + s);
} catch (FileNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
text(p.a,150,150);
}
and my function :
public void WriteByteToFile(byte[] mybytes, String filename){
try {
FileOutputStream FOS = openFileOutput(filename, MODE_PRIVATE);
FOS.write(mybytes);
FOS.close();
} catch (FileNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
System.out.println("done");
}
it is returning a filenotfoundexception .
(i am new at this, so please be patient and understanding)
EDIT ::this is how i am (trying to ) read, (for cerntainly)
ObjectInputStream input = null;
String filename = "testFilemost.srl";
try {
input = new ObjectInputStream(new FileInputStream(new File(new File(getFilesDir(),"")+File.separator+filename)));
} catch (StreamCorruptedException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (FileNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
try {
Person myPersonObject = (Person) input.readObject();
text(myPersonObject.a,150,150);
} catch (OptionalDataException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (ClassNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
try {
input.close();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
and for reading :::
if(mousePressed)
{
Person myPersonObject = new Person();
myPersonObject.a=432;
String filename = "testFilemost.srl";
ObjectOutput out = null;
try {
out = new ObjectOutputStream(new FileOutputStream(new File(getFilesDir(),"")+File.separator+filename));
} catch (FileNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
try {
out.writeObject(myPersonObject);
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
try {
out.close();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}

You don't need to use the 'byte array' approach. There is an easy way to (de)serialize objects.
EDIT: here's the long version of code
Read:
public void read(){
ObjectInputStream input;
String filename = "testFilemost.srl";
try {
input = new ObjectInputStream(new FileInputStream(new File(new File(getFilesDir(),"")+File.separator+filename)));
Person myPersonObject = (Person) input.readObject();
Log.v("serialization","Person a="+myPersonObject.getA());
input.close();
} catch (StreamCorruptedException e) {
e.printStackTrace();
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
} catch (ClassNotFoundException e) {
e.printStackTrace();
}
}
Write:
public void write(){
Person myPersonObject = new Person();
myPersonObject.setA(432);
String filename = "testFilemost.srl";
ObjectOutput out = null;
try {
out = new ObjectOutputStream(new FileOutputStream(new File(getFilesDir(),"")+File.separator+filename));
out.writeObject(myPersonObject);
out.close();
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
}
Person class:
public class Person implements Serializable {
private static final long serialVersionUID = -29238982928391L;
int a;
public int getA(){
return a;
}
public void setA(int newA){
a = newA;
}
}

FileNotFoundException when creating a new FileOutputStream means that one of the intermediate directories didn't exist. Try
file.getParentFile().mkdirs();
before creating the FileOutputStream.

Add this code to manifest.xml
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE"/>
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>
<uses-permission android:name="android.permission.MANAGE_EXTERNAL_STORAGE"/>
Go to phone setting/applications/your_app/permissions/ allow files and media permission. You can ask permission via by code and when user enter app program will ask permission. If you want I can give you code.
All writen and readen objects must be serializable.(Must implements Serializable interface) If A class extends B class, to set B class serializable is enough.
And add this code to writen and readen class:
private static final long serialVersionUID = 1L;
Write to external memory:
public static void writeToExternal(Serializable object, String filename) {
try {
//File root = new File(Environment.getExternalStorageDirectory(), "MyApp");
//or
File root = new File("/storage/emulated/0/MyApp/");
if (!root.exists()) {
root.mkdirs();
}
File file = new File(root, filename);
FileOutputStream fos = new FileOutputStream(file);
ObjectOutput out = new ObjectOutputStream(fos);
out.writeObject(object);
out.flush();
out.close();
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
}
If you want to write to internal memory(This memory is not visible and doesn't need permission. This is your app stored in. For this, you can use getFilesDir() instead of getExternalStorageDirectory(). More about https://developer.android.com/reference/android/content/ContextWrapper#getFilesDir%28%29
https://developer.android.com/reference/android/os/Environment.html#getDataDirectory%28%29
https://gist.github.com/granoeste/5574148
https://source.android.com/docs/core/storage
public static void writeToInternal(Context context, Serializable object, String filename){
try {
//File root1 = new File(context.getFilesDir(), "MyApp");
//or
File root = new File("/data/user/0/com.example.myapplication/files/MyApp/");
if (!root.exists()) {
root.mkdirs();
}
File file = new File(root, filename);
FileOutputStream fos = new FileOutputStream(file);
ObjectOutput out = new ObjectOutputStream(fos);
out.writeObject(object);
out.flush();
out.close();
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
}
Read an object:
public static Object read(String filename) {
try {
File file = new File("/storage/emulated/0/MyApp/" + filename);
FileInputStream fis = new FileInputStream(file);
ObjectInputStream input = new ObjectInputStream(fis);
Object data = (Object) input.readObject();
input.close();
return data;
} catch (StreamCorruptedException e) {
e.printStackTrace();
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
} catch (ClassNotFoundException e) {
e.printStackTrace();
}
return null;
}
When you call read method you must cast to your readen and writen class.(For example Person p = (Person)read("file.txt");
Import all classes and run.