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Convertir un fichier: Uri to File in Android

Quel est le moyen le plus simple de convertir un file:Android.net.Uri en File sous Android?

Essayé ce qui suit mais cela ne fonctionne pas:

 final File file = new File(Environment.getExternalStorageDirectory(), "read.me");
 Uri uri = Uri.fromFile(file);
 File auxFile = new File(uri.toString());
 assertEquals(file.getAbsolutePath(), auxFile.getAbsolutePath());
317
hpique

Ce que tu veux c'est ...

new File(uri.getPath());

... et pas...

new File(uri.toString());

REMARQUE: uri.toString() renvoie une chaîne au format: "file:///mnt/sdcard/myPicture.jpg", alors que uri.getPath() renvoie une chaîne au format: "/mnt/sdcard/myPicture.jpg".

660
Adil Hussain

Après une longue recherche, voici ce qui a fonctionné pour moi:

File file = new File(getPath(uri));


public String getPath(Uri uri) 
    {
        String[] projection = { MediaStore.Images.Media.DATA };
        Cursor cursor = getContentResolver().query(uri, projection, null, null, null);
        if (cursor == null) return null;
        int column_index =             cursor.getColumnIndexOrThrow(MediaStore.Images.Media.DATA);
        cursor.moveToFirst();
        String s=cursor.getString(column_index);
        cursor.close();
        return s;
    }
33
Sanket Berde

EDIT: Désolé, j'aurais dû mieux tester avant. Cela devrait fonctionner:

new File(new URI(androidURI.toString()));

L'URI est Java.net.URI.

27
Matthew Flaschen

Rien de tout cela ne fonctionne pour moi. J'ai trouvé cela être la solution de travail. Mais mon cas est spécifique aux images .

String[] filePathColumn = { MediaStore.Images.Media.DATA };
Cursor cursor = getActivity().getContentResolver().query(uri, filePathColumn, null, null, null);
cursor.moveToFirst();
int columnIndex = cursor.getColumnIndex(filePathColumn[0]);
String filePath = cursor.getString(columnIndex);
cursor.close();
11
Jacek Kwiecień

utilisation 

InputStream inputStream = getContentResolver().openInputStream(uri);    

directement et copiez le fichier. Regarde aussi: 

https://developer.Android.com/guide/topics/providers/document-provider.html

Meilleure solution

Créer une simple classe Java FileUtil et utiliser pour créer, copier et renommer le fichier

Je suis utiliser uri.toString() et uri.getPath() mais ne travaille pas pour moi ..__ J'ai finalement trouvé cette solution.

import Android.content.Context;
import Android.database.Cursor;
import Android.net.Uri;
import Android.provider.OpenableColumns;
import Android.util.Log;

import Java.io.File;
import Java.io.FileNotFoundException;
import Java.io.FileOutputStream;
import Java.io.IOException;
import Java.io.InputStream;
import Java.io.OutputStream;

public class FileUtil {
    private static final int EOF = -1;
    private static final int DEFAULT_BUFFER_SIZE = 1024 * 4;

    private FileUtil() {

    }

    public static File from(Context context, Uri uri) throws IOException {
        InputStream inputStream = context.getContentResolver().openInputStream(uri);
        String fileName = getFileName(context, uri);
        String[] splitName = splitFileName(fileName);
        File tempFile = File.createTempFile(splitName[0], splitName[1]);
        tempFile = rename(tempFile, fileName);
        tempFile.deleteOnExit();
        FileOutputStream out = null;
        try {
            out = new FileOutputStream(tempFile);
        } catch (FileNotFoundException e) {
            e.printStackTrace();
        }
        if (inputStream != null) {
            copy(inputStream, out);
            inputStream.close();
        }

        if (out != null) {
            out.close();
        }
        return tempFile;
    }

    private static String[] splitFileName(String fileName) {
        String name = fileName;
        String extension = "";
        int i = fileName.lastIndexOf(".");
        if (i != -1) {
            name = fileName.substring(0, i);
            extension = fileName.substring(i);
        }

        return new String[]{name, extension};
    }

    private static String getFileName(Context context, Uri uri) {
        String result = null;
        if (uri.getScheme().equals("content")) {
            Cursor cursor = context.getContentResolver().query(uri, null, null, null, null);
            try {
                if (cursor != null && cursor.moveToFirst()) {
                    result = cursor.getString(cursor.getColumnIndex(OpenableColumns.DISPLAY_NAME));
                }
            } catch (Exception e) {
                e.printStackTrace();
            } finally {
                if (cursor != null) {
                    cursor.close();
                }
            }
        }
        if (result == null) {
            result = uri.getPath();
            int cut = result.lastIndexOf(File.separator);
            if (cut != -1) {
                result = result.substring(cut + 1);
            }
        }
        return result;
    }

    private static File rename(File file, String newName) {
        File newFile = new File(file.getParent(), newName);
        if (!newFile.equals(file)) {
            if (newFile.exists() && newFile.delete()) {
                Log.d("FileUtil", "Delete old " + newName + " file");
            }
            if (file.renameTo(newFile)) {
                Log.d("FileUtil", "Rename file to " + newName);
            }
        }
        return newFile;
    }

    private static long copy(InputStream input, OutputStream output) throws IOException {
        long count = 0;
        int n;
        byte[] buffer = new byte[DEFAULT_BUFFER_SIZE];
        while (EOF != (n = input.read(buffer))) {
            output.write(buffer, 0, n);
            count += n;
        }
        return count;
    }
}

Utilisez la classe FileUtil dans votre code

try {
         File file = FileUtil.from(MainActivity.this,fileUri);
         Log.d("file", "File...:::: uti - "+file .getPath()+" file -" + file + " : " + file .exists());

  } catch (IOException e) {
          e.printStackTrace();
  }
5
vishwa

Avec Kotlin, c'est encore plus simple:

val file = File(uri.path)

Ou si vous utilisez Extensions Kotlin pour Android :

val file = uri.toFile()
4

J'ai fait ceci comme suit:

try {
    readImageInformation(new File(contentUri.getPath()));

} catch (IOException e) {
    readImageInformation(new File(getRealPathFromURI(context,
                contentUri)));
}

public static String getRealPathFromURI(Context context, Uri contentUri) {
        String[] proj = { MediaStore.Images.Media.DATA };
        Cursor cursor = context.getContentResolver().query(contentUri, proj,
                null, null, null);
        int column_index = cursor
                .getColumnIndexOrThrow(MediaStore.Images.Media.DATA);
        cursor.moveToFirst();
        return cursor.getString(column_index);
}

En gros, j’essaie d’abord d’utiliser un fichier, c’est-à-dire une photo prise par l’appareil photo et sauvegardée sur une carte SD. Cela ne fonctionne pas pour les images renvoyées par: Intention photoPickerIntent = new Intent (Intent.ACTION_PICK); Dans ce cas, il est nécessaire de convertir Uri en chemin réel par la fonction getRealPathFromURI() . La conclusion est donc que cela dépend du type d’Uri que vous voulez convertir en fichier.

1
Kovács Ede

@CommonsWare a très bien expliqué toutes les choses. Et nous devrions vraiment utiliser la solution qu'il a proposée. 

En passant, seules les informations sur lesquelles nous pouvions compter lorsque nous interrogions ContentResolver sont le nom et la taille d'un fichier, comme indiqué ici: Récupération des informations sur le fichier | Développeurs Android

Comme vous pouvez le constater, il existe une interface OpenableColumns qui ne contient que deux champs: DISPLAY_NAME et SIZE.

Dans mon cas, il me fallait récupérer des informations EXIF ​​sur une image JPEG et les faire pivoter si nécessaire avant de les envoyer à un serveur. Pour ce faire, j'ai copié le contenu d'un fichier dans un fichier temporaire en utilisant ContentResolver et openInputStream()

1
Bogdan Kornev

Dans ce cas, en particulier sur Android, la procédure d'octets est généralement plus rapide.

Avec cela, j'ai résolu le problème en configurant une classe FileHelper à qui il incombe de gérer les octets de lecture/écriture de/vers fichier par flux et une classe UriHelper à laquelle il incombe de déterminer le chemin d'Uri et d'obtenir la permission.

Autant que l'on sache, string.getBytes((charset == null) ? DEFAULT_CHARSET:charset) peut nous aider à transférer la chaîne que vous voulez en octets dont vous avez besoin.

Comment laisser UriHelper et FileHelper vous permettre de copier une image notée par Uri dans un fichier, vous pouvez exécuter: 

FileHelper.getInstance().copy(UriHelper.getInstance().toFile(uri_of_a_picture)
                        , FileHelper.getInstance().createExternalFile(null, UriHelper.getInstance().generateFileNameBasedOnTimeStamp()
                                + UriHelper.getInstance().getFileName(uri_of_a_picture, context), context)
                );

à propos de mon UriHelper:

public class UriHelper {
private static UriHelper INSTANCE = new UriHelper();

public static UriHelper getInstance() {
    return INSTANCE;
}

@SuppressLint("SimpleDateFormat")
public String generateFileNameBasedOnTimeStamp() {
    return new SimpleDateFormat("yyyyMMdd_hhmmss").format(new Date()) + ".jpeg";
}

/**
 * if uri.getScheme.equals("content"), open it with a content resolver.
 * if the uri.Scheme.equals("file"), open it using normal file methods.
 */
//

public File toFile(Uri uri) {
    if (uri == null) return null;
    Logger.d(">>> uri path:" + uri.getPath());
    Logger.d(">>> uri string:" + uri.toString());
    return new File(uri.getPath());
}

public DocumentFile toDocumentFile(Uri uri) {
    if (uri == null) return null;
    Logger.d(">>> uri path:" + uri.getPath());
    Logger.d(">>> uri string:" + uri.toString());
    return DocumentFile.fromFile(new File(uri.getPath()));
}

public Uri toUri(File file) {
    if (file == null) return null;
    Logger.d(">>> file path:" + file.getAbsolutePath());
    return Uri.fromFile(file); //returns an immutable URI reference representing the file
}

public String getPath(Uri uri, Context context) {
    if (uri == null) return null;
    if (uri.getScheme() == null) return null;
    Logger.d(">>> uri path:" + uri.getPath());
    Logger.d(">>> uri string:" + uri.toString());
    String path;
    if (uri.getScheme().equals("content")) {
        //Cursor cursor = context.getContentResolver().query(uri, new String[] {MediaStore.Images.ImageColumns.DATA}, null, null, null);
        Cursor cursor = context.getContentResolver().query(uri, null, null, null, null);
        if (cursor == null) {
            Logger.e("!!! cursor is null");
            return null;
        }
        if (cursor.getCount() >= 0) {
            Logger.d("... the numbers of rows:" + cursor.getCount()
                        + "and the numbers of columns:" + cursor.getColumnCount());
            if (cursor.isBeforeFirst()) {
                while (cursor.moveToNext()) {
                    StringBuilder stringBuilder = new StringBuilder();
                    for (int i = 0; i<cursor.getColumnCount(); i++) {
                        stringBuilder.append("... iterating cursor.getString(" + i +"(" + cursor.getColumnName(i) + ")):" + cursor.getString(i));
                        stringBuilder.append("\n");
                    }
                    Logger.d(stringBuilder.toString());
                }
            } else {
                cursor.moveToFirst();
                do {
                    StringBuilder stringBuilder = new StringBuilder();
                    for (int i = 0; i<cursor.getColumnCount(); i++) {
                        stringBuilder.append("... iterating cursor.getString(" + i +"(" + cursor.getColumnName(i) + ")):" + cursor.getString(i));
                        stringBuilder.append("\n");
                    }
                    Logger.d(stringBuilder.toString());
                } while (cursor.moveToNext());
            }
            path = uri.getPath();
            cursor.close();
            Logger.d("... content scheme:" + uri.getScheme() + "  and return:" + path);
            return path;
        } else {
            path = uri.getPath();
            Logger.d("... content scheme:" + uri.getScheme()
                    + " but the numbers of rows in the cursor is < 0:" + cursor.getCount()
                    + "  and return:" + path);
            return path;
        }
    } else {
        path = uri.getPath();
        Logger.d("... not content scheme:" + uri.getScheme() + "  and return:" + path);
        return path;
    }
}

public String getFileName(Uri uri, Context context) {
    if (uri == null) return null;
    if (uri.getScheme() == null) return null;
    Logger.d(">>> uri path:" + uri.getPath());
    Logger.d(">>> uri string:" + uri.toString());
    String path;
    if (uri.getScheme().equals("content")) {
        //Cursor cursor = context.getContentResolver().query(uri, new String[] {MediaStore.Images.ImageColumns.DATA}, null, null, null);
        Cursor cursor = context.getContentResolver().query(uri, null, null, null, null);
        if (cursor == null) {
            Logger.e("!!! cursor is null");
            return null;
        }
        if (cursor.getCount() >= 0) {
            Logger.d("... the numbers of rows:" + cursor.getCount()
                    + "and the numbers of columns:" + cursor.getColumnCount());
            if (cursor.isBeforeFirst()) {
                while (cursor.moveToNext()) {
                    StringBuilder stringBuilder = new StringBuilder();
                    for (int i = 0; i<cursor.getColumnCount(); i++) {
                        stringBuilder.append("... iterating cursor.getString(" + i +"(" + cursor.getColumnName(i) + ")):" + cursor.getString(i));
                        stringBuilder.append("\n");
                    }
                    Logger.d(stringBuilder.toString());
                }
            } else {
                cursor.moveToFirst();
                do {
                    StringBuilder stringBuilder = new StringBuilder();
                    for (int i = 0; i<cursor.getColumnCount(); i++) {
                        stringBuilder.append("... iterating cursor.getString(" + i +"(" + cursor.getColumnName(i) + ")):" + cursor.getString(i));
                        stringBuilder.append("\n");
                    }
                    Logger.d(stringBuilder.toString());
                } while (cursor.moveToNext());
            }
            cursor.moveToFirst();
            path = cursor.getString(cursor.getColumnIndex(MediaStore.Images.ImageColumns.DISPLAY_NAME));
            cursor.close();
            Logger.d("... content scheme:" + uri.getScheme() + "  and return:" + path);
            return path;
        } else {
            path = uri.getLastPathSegment();
            Logger.d("... content scheme:" + uri.getScheme()
                    + " but the numbers of rows in the cursor is < 0:" + cursor.getCount()
                    + "  and return:" + path);
            return path;
        }
    } else {
        path = uri.getLastPathSegment();
        Logger.d("... not content scheme:" + uri.getScheme() + "  and return:" + path);
        return path;
    }
}

}

à propos de mon FileHelper:

public class FileHelper {
private static final String DEFAULT_DIR_NAME = "AmoFromTaiwan";
private static final int DEFAULT_BUFFER_SIZE = 1024;
private static final Charset DEFAULT_CHARSET = Charset.forName("UTF-8");
private static final int EOF = -1;
private static FileHelper INSTANCE = new FileHelper();

public static FileHelper getInstance() {
    return INSTANCE;
}

private boolean isExternalStorageWritable(Context context) {
    /*
    String state = Environment.getExternalStorageState();
    return Environment.MEDIA_MOUNTED.equals(state);
    */
    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
        if (context.checkSelfPermission(Android.Manifest.permission.WRITE_EXTERNAL_STORAGE) == PackageManager.PERMISSION_GRANTED) {
            return true;
        } else {
            Logger.e("!!! checkSelfPermission() not granted");
            return false;
        }
    } else { //permission is automatically granted on sdk<23 upon installation
        return true;
    }
}

private boolean isExternalStorageReadable(Context context) {
    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
        if (context.checkSelfPermission(Android.Manifest.permission.READ_EXTERNAL_STORAGE) == PackageManager.PERMISSION_GRANTED) {
            return true;
        } else {
            Logger.e("!!! checkSelfPermission() not granted");
            return false;
        }
    } else { //permission is automatically granted on sdk<23 upon installation
        return true;
    }
}

@SuppressLint("SimpleDateFormat")
private String generateFileNameBasedOnTimeStamp() {
    return new SimpleDateFormat("yyyyMMdd_hhmmss").format(new Date()) + ".jpeg";
}

public File createExternalFile(String dir_name, String file_name, Context context) {
    String dir_path;
    String file_path;
    File dir ;
    File file;
    if (!isExternalStorageWritable(context)) {
        Logger.e("!!! external storage not writable");
        return null;
    }
    if (dir_name == null) {
        dir_path = Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_PICTURES).getAbsolutePath() + File.separator + DEFAULT_DIR_NAME;
    } else {
        dir_path = Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_PICTURES).getAbsolutePath() + File.separator + dir_name;
    }
    Logger.d("... going to access an external dir:" + dir_path);
    dir = new File(dir_path);
    if (!dir.exists()) {
        Logger.d("... going to mkdirs:" + dir_path);
        if (!dir.mkdirs()) {
            Logger.e("!!! failed to mkdirs");
            return null;
        }
    }
    if (file_name == null) {
        file_path = dir_path + File.separator + generateFileNameBasedOnTimeStamp();
    } else {
        file_path = dir_path + File.separator + file_name;
    }
    Logger.d("... going to return an external dir:" + file_path);
    file = new File(file_path);
    if (file.exists()) {
        Logger.d("... before creating to delete an external dir:" + file.getAbsolutePath());
        if (!file.delete()) {
            Logger.e("!!! failed to delete file");
            return null;
        }
    }
    return file;
}

public File createInternalFile(String dir_name, String file_name, Context context) {
    String dir_path;
    String file_path;
    File dir ;
    File file;
    if (dir_name == null) {
        dir = new ContextWrapper(context).getDir(DEFAULT_DIR_NAME, Context.MODE_PRIVATE);
    } else {
        dir = new ContextWrapper(context).getDir(dir_name, Context.MODE_PRIVATE);
    }
    dir_path = dir.getAbsolutePath();
    Logger.d("... going to access an internal dir:" + dir_path);
    if (!dir.exists()) {
        Logger.d("... going to mkdirs:" + dir_path);
        if (!dir.mkdirs()) {
            Logger.e("!!! mkdirs failed");
            return null;
        }
    }
    if (file_name == null) {
        file = new File(dir, generateFileNameBasedOnTimeStamp());
    } else {
        file = new File(dir, file_name);
    }
    file_path = file.getAbsolutePath();
    Logger.d("... going to return an internal dir:" + file_path);
    if (file.exists()) {
        Logger.d("... before creating to delete an external dir:" + file.getAbsolutePath());
        if (!file.delete()) {
            Logger.e("!!! failed to delete file");
            return null;
        }
    }
    return file;
}

public File getExternalFile(String dir_name, String file_name, Context context) {
    String dir_path;
    String file_path;
    File file;
    if (!isExternalStorageWritable(context)) {
        Logger.e("!!! external storage not writable");
        return null;
    }
    if (dir_name == null) {
        dir_path = Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_PICTURES).getAbsolutePath() + File.separator + DEFAULT_DIR_NAME;
    } else {
        dir_path = Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_PICTURES).getAbsolutePath() + File.separator + dir_name;
    }
    if (file_name == null) {
        file_path = dir_path;
    } else {
        file_path = dir_path + File.separator + file_name;
    }
    Logger.d("... going to return an external file:" + file_path);
    file = new File(file_path);
    if (file.exists()) {
        Logger.d("... file exists:" + file.getAbsolutePath());
    } else {
        Logger.e("!!! file does't exist:" + file.getAbsolutePath());
    }
    return file;
}

public File getInternalFile(String dir_name, String file_name, Context context) {
    String file_path;
    File dir ;
    File file;
    if (dir_name == null) {
        dir = new ContextWrapper(context).getDir(DEFAULT_DIR_NAME, Context.MODE_PRIVATE);
    } else {
        dir = new ContextWrapper(context).getDir(dir_name, Context.MODE_PRIVATE);
    }
    if (file_name == null) {
        file = new File(dir.getAbsolutePath());
    } else {
        file = new File(dir, file_name);
    }
    file_path = file.getAbsolutePath();
    Logger.d("... going to return an internal dir:" + file_path);
    if (file.exists()) {
        Logger.d("... file exists:" + file.getAbsolutePath());
    } else {
        Logger.e("!!! file does't exist:" + file.getAbsolutePath());
    }
    return file;
}

private byte[] readBytesFromFile(File file) {
    Logger.d(">>> path:" + file.getAbsolutePath());
    FileInputStream fis;
    long file_length;
    byte[] buffer;
    int offset = 0;
    int next = 0;
    if (!file.exists()) {
        Logger.e("!!! file doesn't exists");
        return null;
    }
    if (file.length() > Integer.MAX_VALUE) {
        Logger.e("!!! file length is out of max of int");
        return null;
    } else {
        file_length = file.length();
    }
    try {
        fis = new FileInputStream(file);
        //buffer = new byte[(int) file_length];
        buffer = new byte[(int) file.length()];
        long time_start = System.currentTimeMillis();
        while (true) {
            Logger.d("... now next:" + next + " and offset:" + offset);
            if (System.currentTimeMillis() - time_start > 1000) {
                Logger.e("!!! left due to time out");
                break;
            }
            next = fis.read(buffer, offset, (buffer.length-offset));
            if (next < 0 || offset >= buffer.length) {
                Logger.d("... completed to read");
                break;
            }
            offset += next;
        }
        //if (offset < buffer.length) {
        if (offset < (int) file_length) {
            Logger.e("!!! not complete to read");
            return null;
        }
        fis.close();
        return buffer;
    } catch (IOException e) {
        e.printStackTrace();
        Logger.e("!!! IOException");
        return null;
    }
}

public byte[] readBytesFromFile(File file, boolean is_fis_fos_only) {
    if (file == null) return null;
    if (is_fis_fos_only) {
        return readBytesFromFile(file);
    }
    Logger.d(">>> path:" + file.getAbsolutePath());
    FileInputStream fis;
    BufferedInputStream bis;
    ByteArrayOutputStream bos;
    byte[] buf = new byte[(int) file.length()];
    int num_read;
    if (!file.exists()) {
        Logger.e("!!! file doesn't exists");
        return null;
    }
    try {
        fis = new FileInputStream(file);
        bis = new BufferedInputStream(fis);
        bos = new ByteArrayOutputStream();
        long time_start = System.currentTimeMillis();
        while (true) {
            if (System.currentTimeMillis() - time_start > 1000) {
                Logger.e("!!! left due to time out");
                break;
            }
            num_read = bis.read(buf, 0, buf.length); //1024 bytes per call
            if (num_read < 0) break;
            bos.write(buf, 0, num_read);
        }
        buf = bos.toByteArray();
        fis.close();
        bis.close();
        bos.close();
        return buf;
    } catch (FileNotFoundException e) {
        e.printStackTrace();
        Logger.e("!!! FileNotFoundException");
        return null;
    } catch (IOException e) {
        e.printStackTrace();
        Logger.e("!!! IOException");
        return null;
    }
}

/**
 * streams (InputStream and OutputStream) transfer binary data
 * if to write a string to a stream, must first convert it to bytes, or in other words encode it
 */
public boolean writeStringToFile(File file, String string, Charset charset) {
    if (file == null) return false;
    if (string == null) return false;
    return writeBytesToFile(file, string.getBytes((charset == null) ? DEFAULT_CHARSET:charset));
}

public boolean writeBytesToFile(File file, byte[] data) {
    if (file == null) return false;
    if (data == null) return false;
    FileOutputStream fos;
    BufferedOutputStream bos;
    try {
        fos = new FileOutputStream(file);
        bos = new BufferedOutputStream(fos);
        bos.write(data, 0, data.length);
        bos.flush();
        bos.close();
        fos.close();
    } catch (IOException e) {
        e.printStackTrace();
        Logger.e("!!! IOException");
        return false;
    }
    return true;
}

/**
 * io blocks until some input/output is available.
 */
public boolean copy(File source, File destination) {
    if (source == null || destination == null) return false;
    Logger.d(">>> source:" + source.getAbsolutePath() + ", destination:" + destination.getAbsolutePath());
    try {
        FileInputStream fis = new FileInputStream(source);
        FileOutputStream fos = new FileOutputStream(destination);
        byte[] buffer = new byte[(int) source.length()];
        int len;
        while (EOF != (len = fis.read(buffer))) {
            fos.write(buffer, 0, len);
        }
        if (true) { //debug
            byte[] copies = readBytesFromFile(destination);
            if (copies != null) {
                int copy_len = copies.length;
                Logger.d("... stream read and write done for " + copy_len + " bytes");
            }
        }
        return destination.length() != 0;
    } catch (IOException e) {
        e.printStackTrace();
        return false;
    }
}

public void list(final String path, final String end, final List<File> files) {
    Logger.d(">>> path:" + path + ", end:" + end);
    File file = new File(path);
    if (file.isDirectory()) {
        for (File child : file.listFiles()){
            list(child.getAbsolutePath(), end, files);
        }
    } else if (file.isFile()) {
        if (end.equals("")) {
            files.add(file);
        } else {
            if (file.getName().endsWith(end)) files.add(file);
        }
    }
}

public String[] splitFileName(File file, String split) {
    String path;
    String ext;
    int lastIndexOfSplit = file.getAbsolutePath().lastIndexOf(split);
    if (lastIndexOfSplit < 0) {
        path = file.getAbsolutePath();
        ext = "";
    } else {
        path = file.getAbsolutePath().substring(0, lastIndexOfSplit);
        ext = file.getAbsolutePath().substring(lastIndexOfSplit);
    }
    return new String[] {path, ext};
}

public File rename(File old_file, String new_name) {
    if (old_file == null || new_name == null) return null;
    Logger.d(">>> old file path:" + old_file.getAbsolutePath() + ", new file name:" + new_name);
    File new_file = new File(old_file, new_name);
    if (!old_file.equals(new_file)) {
        if (new_file.exists()) { //if find out previous file/dir at new path name exists
            if (new_file.delete()) {
                Logger.d("... succeeded to delete previous file at new abstract path name:" + new_file.getAbsolutePath());
            } else {
                Logger.e("!!! failed to delete previous file at new abstract path name");
                return null;
            }
        }
        if (old_file.renameTo(new_file)) {
            Logger.d("... succeeded to rename old file to new abstract path name:" + new_file.getAbsolutePath());
        } else {
            Logger.e("!!! failed to rename old file to new abstract path name");
        }
    } else {
        Logger.d("... new and old file have the equal abstract path name:" + new_file.getAbsolutePath());
    }
    return new_file;
}

public boolean remove(final String path, final String end) {
    Logger.d(">>> path:" + path + ", end:" + end);
    File file = new File(path);
    boolean result = false;
    if (file.isDirectory()) {
        for (File child : file.listFiles()){
            result = remove(child.getAbsolutePath(), end);
        }
    } else if (file.isFile()) {
        if (end.equals("")) {
            result = file.delete();
        } else {
            if (file.getName().endsWith(end)) result = file.delete();
        }
    } else {
        Logger.e("!!! child is not file or directory");
    }
    return result;
}

@TargetApi(Build.VERSION_CODES.O)
public byte[] readNIOBytesFromFile(String path) throws IOException {
    Logger.d(">>> path:" + path);
    if (!Files.exists(Paths.get(path), LinkOption.NOFOLLOW_LINKS)) {
        Logger.e("!!! file doesn't exists");
        return null;
    } else {
        return Files.readAllBytes(Paths.get(path));
    }
}

@TargetApi(Build.VERSION_CODES.O)
public File writeNIOBytesToFile(String dir, String name, byte[] data) {
    Logger.d(">>> dir:" + dir + ", name:" + name);
    Path path_dir;
    Path path_file;
    try {
        if (!Files.exists(Paths.get(dir), LinkOption.NOFOLLOW_LINKS)) {
            Logger.d("... make a dir");
            path_dir = Files.createDirectories(Paths.get(dir));
            if (path_dir == null) {
                Logger.e("!!! failed to make a dir");
                return null;
            }
        }
        path_file = Files.write(Paths.get(name), data);
        return path_file.toFile();
    } catch (IOException e) {
        e.printStackTrace();
        Logger.e("!!! IOException");
        return null;
    }
}

@TargetApi(Build.VERSION_CODES.O)
public void listNIO(final String dir, final String end, final List<File> files) throws IOException {
    Logger.d(">>> dir:" + dir + ", end:" + end);
    Files.walkFileTree(Paths.get(dir), new FileVisitor<Path>() {
        @Override
        public FileVisitResult preVisitDirectory(Path dir, BasicFileAttributes attrs) {
            Logger.d("... file:" + dir.getFileName());
            return FileVisitResult.CONTINUE;
        }

        @Override
        public FileVisitResult visitFile(Path file, BasicFileAttributes attrs) {
            Logger.d("... file:" + file.getFileName());
            if (end.equals("")) {
                files.add(file.toFile());
            } else {
                if (file.endsWith(end)) files.add(file.toFile());
            }
            return FileVisitResult.CONTINUE;
        }

        @Override
        public FileVisitResult visitFileFailed(Path file, IOException exc) {
            Logger.d("... file:" + file.getFileName());
            if (end.equals("")) {
                files.add(file.toFile());
            } else {
                if (file.endsWith(end)) files.add(file.toFile());
            }
            return FileVisitResult.CONTINUE;
        }

        @Override
        public FileVisitResult postVisitDirectory(Path dir, IOException exc) {
            Logger.d("... file:" + dir.getFileName());
            return FileVisitResult.CONTINUE;
        }
    });
}

/**
 * recursion
 */
private int factorial (int x) {
    if (x > 1) return (x*(factorial(x-1)));
    else if (x == 1) return x;
    else return 0;
}

}

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