Develop Reference

how can i copy file in data directory

i want to copy file from asset to other application data directory.i have also given root acess to it.but this code doesn't work.its work on extenal storage directory .but not copy file in data directory..
public void onClick(View arg1){
String command[] = { "su", "-c", "ls", "/data" };
Shell shell = new Shell();
String text = shell.sendShellCommand(command);
if (new File((Object)Environment.getDataDirectory() + "/data/com.my/shared_pref/com.myxml").exists()) {
Toast.makeText(getApplicationContext(),"copied",Toast.LENGTH_LONG).show();
MainActivity.this.copyAssets();
}
else{
Toast.makeText(getApplicationContext(),"error! copy failed ",Toast.LENGTH_LONG).show();
private void copyAssets()
{
AssetManager assetManager = getAssets();
String[] files = null;
InputStream in = null;
OutputStream out = null;
String filename =
"com.my.xml" ;
try
{
in = assetManager.open( filename);
out = new FileOutputStream((Environment.getDataDirectory().toString() +"/data/com.my/shared_pref/" + filename));
copyFile(in, out);
in.close();
in = null;
out.flush();
out.close();
out = null;
}
catch (IOException e)
{
Log. e ( "tag" , "Failed to copy asset file: " , e);
}
}
private void copyFile(InputStream in, OutputStream out) throws IOException
{
byte[] buffer = new byte[1024];
int read;
while ((read = in.read(buffer)) != -1)
{
out.write(buffer, 0, read);
}
}
if anyone knows how to do it?
Pleaase suggest me.!!
Thanks.!!

This is exactly what you need. This code copies sample.apk from assets to the application data directory. You can change the path to anywhere you want.
private String copyAssets() {
AssetManager assetManager = getActivity().getAssets();
InputStream in = null;
OutputStream out = null;
String filename = "sample.apk";
String path = Environment.getExternalStorageDirectory()
+ "/Android/data/"
+ getActivity().getPackageName()
+ "/files";
try {
in = assetManager.open("files/" + filename);
File outFile = new File(path);
if (!outFile.exists()) {
outFile.mkdirs();
}
out = new FileOutputStream(outFile + "/" + filename);
copyFile(in, out);
} catch (Exception e) {
e.printStackTrace();
} finally {
if (in != null) {
try {
in.close();
} catch (Exception e) {
e.printStackTrace();
}
}
if (out != null) {
try {
out.close();
} catch (Exception e) {
e.printStackTrace();
}
}
}
return path + "/" + filename;
}
private void copyFile(InputStream in, OutputStream out) throws IOException {
byte[] buffer = new byte[1024];
int read;
while ((read = in.read(buffer)) != -1) {
out.write(buffer, 0, read);
}
}

Use this code. I used this code in my project, Got it on net somewhare, it works.
private void copyDataBase() throws IOException
{
//Open your local db as the input stream
InputStream myInput = _context.getAssets().open(DB_NAME);
// Path to db
String outFileName = DB_PATH + DB_NAME;
//Open the empty db as the output stream
OutputStream myOutput = new FileOutputStream(outFileName);
//transfer bytes from the inputfile to the outputfile
byte[] buffer = new byte[1024];
int length;
while ((length = myInput.read(buffer))>0)
{
myOutput.write(buffer, 0, length);
}
//Close the streams
myOutput.flush();
myOutput.close();
myInput.close();
}

Android bluetooth client receive xml

I'm new at android development and I'm creating simple bluetooth app that can receive xml file and save xml file values to database. But how can I receive xml file from bytes array? Is it possible? After searchinf I found this question and based ont that question I try to save byte array to file. But how I need to test it? I can't find my file in my phone.
case Constants.MESSAGE_READ:
byte[] readBuffer = (byte[]) msg.obj;
try {
String path = activity.getFilesDir() + "/myFile.xml";
Log.d("MuTestClass", path);
FileOutputStream stream = new FileOutputStream(path);
stream.write(readBuffer);
stream.close();
} catch (Exception e1) {
e1.printStackTrace();
}
break;

You can use:
class Utils{
public static InputStream openFile(String filename) throws IOException{
AssetManager assManager = getApplicationContext().getAssets();
InputStream is = null;
is = assManager.open(filename);
return new BufferedInputStream(is);
}
public static byte[] readBytes(InputStream inputStream) throws IOException {
ByteArrayOutputStream byteBuffer = new ByteArrayOutputStream();
int bufferSize = 1024;
byte[] buffer = new byte[bufferSize];
int len = 0;
while ((len = inputStream.read(buffer)) != -1) {
byteBuffer.write(buffer, 0, len);
}
return byteBuffer.toByteArray();
}
}
like this:
try {
Utils.readBytes(Utils.openFile("something.xml"));
} catch (IOException e) {
e.printStackTrace();
}

Copy multiple files from asset to internal storage

This is the original code for copying one file from asset to internal storage I found online:
Context Context = getApplicationContext();
String DestinationFile = Context.getFilesDir().getPath() + File.separator + "DB.sqlite";
if (!new File(DestinationFile).exists()) {
try {
CopyFromAssetsToStorage(Context, "Database/DB.sqlite", DestinationFile);
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
private void CopyFromAssetsToStorage(Context Context, String SourceFile, String DestinationFile) throws IOException {
InputStream IS = Context.getAssets().open(SourceFile);
OutputStream OS = new FileOutputStream(DestinationFile);
CopyStream(IS, OS);
OS.flush();
OS.close();
IS.close();
}
private void CopyStream(InputStream Input, OutputStream Output) throws IOException {
byte[] buffer = new byte[5120];
int length = Input.read(buffer);
while (length > 0) {
Output.write(buffer, 0, length);
length = Input.read(buffer);
}
}
The above code is working fine for copying one file. However, what I want is to copy multiple files instead of one file. Following MT8, I modified my the code to below:
public class MainActivity extends Activity{
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
ArrayList<String> destFiles = new ArrayList<String>();
destFiles.add("FileB.jpg");
destFiles.add("FileC.jpg");
destFiles.add("FileD.jpg");
for(int i =0 ; i < destFiles.size(); i++) {
Context Context = getApplicationContext();
String DestinationFile = Context.getFilesDir().getPath() + File.separator + "FileA.db";
if (!new File(DestinationFile).exists()) {
try {
CopyFromAssetsToStorage(Context, "database/FileA.db", destFiles.get(i));
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
}
private void CopyFromAssetsToStorage(Context Context, String SourceFile, String DestinationFile) throws IOException {
InputStream IS = Context.getAssets().open(SourceFile);
OutputStream OS = new FileOutputStream(DestinationFile);
CopyStream(IS, OS);
OS.flush();
OS.close();
IS.close();
}
private void CopyStream(InputStream Input, OutputStream Output) throws IOException {
byte[] buffer = new byte[5120];
int length = Input.read(buffer);
while (length > 0) {
Output.write(buffer, 0, length);
length = Input.read(buffer);
}
}
}
However, the files won't be copied. Any part that I did wrongly?

Step 1 : u need to put the All files name in Arraylist first say ArrayList<String> destFiles .
ArrayList<String> destFiles = new ArrayList<String>();
destFiles.add("FileA");
destFiles.add("FileB");
destFiles.add("FileC");
Step 2 : For loop :
for(int i=0;i<destFiles.size;i++)
{
Context Context = getApplicationContext();
String DestinationFile = Context.getFilesDir().getPath() + File.separator + "DB.sqlite";
if (!new File(DestinationFile).exists()) {
try {
CopyFromAssetsToStorage(Context, "Database/DB.sqlite", destFiles.get(i));
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
private void CopyFromAssetsToStorage(Context Context, String SourceFile, String DestinationFile) throws IOException {
InputStream IS = Context.getAssets().open(SourceFile);
OutputStream OS = new FileOutputStream(DestinationFile);
CopyStream(IS, OS);
OS.flush();
OS.close();
IS.close();
}
private void CopyStream(InputStream Input, OutputStream Output) throws IOException {
byte[] buffer = new byte[5120];
int length = Input.read(buffer);
while (length > 0) {
Output.write(buffer, 0, length);
length = Input.read(buffer);
}
}
}

You can copy all the data from Asset folder into Internal Storage (Download Folder of Android), Call the copyAsset() function in onCreate.
private void copyAssets() {
AssetManager assetManager = getAssets();
String[] files = null;
try {
files = assetManager.list("");
} catch (IOException e) {
Log.e("tag", "Failed to get asset file list.", e);
}
for (String filename : files) {
InputStream in = null;
OutputStream out = null;
try {
in = assetManager.open(filename);
String outDir = Environment.getExternalStorageDirectory().getAbsolutePath() + "/Download/";
File outFile = new File(outDir, filename);
out = new FileOutputStream(outFile);
copyFile(in, out);
in.close();
in = null;
out.flush();
out.close();
out = null;
} catch (IOException e) {
Log.e("tag", "Failed to copy asset file: " + filename, e);
}
}
}
private void copyFile(InputStream in, OutputStream out) throws IOException {
byte[] buffer = new byte[1024];
int read;
while ((read = in.read(buffer)) != -1) {
out.write(buffer, 0, read);
}
}

Android: Accessing File from Internal Storage Using RandomAccessFile

I am creating an app that needs to read data from a file. I was initially reading it from the assets folder using a BufferedReader and an InputStreamReader but I was running into memory issues (see Android: File Reading - OutOfMemory Issue). One suggestion was to copy the data from the assets folder to the internal storage (not the SD card) and then access it via RandomAccessFile. So I looked up how to copy files from the assets to internal storage and I found 2 sources:
https://groups.google.com/forum/?fromgroups=#!topic/android-developers/RpXiMYV48Ww
http://developergoodies.blogspot.com/2012/11/copy-android-asset-to-internal-storage.html
I decided to use the code from the second one and modified it for my file. So it looks like this:
public void copyFile() {
//Open your file in assets
Context context = getApplicationContext();
String destinationFile = context.getFilesDir().getPath() + File.separator + "text.txt";
if (!new File(destinationFile).exists()) {
try {
copyFromAssetsToStorage(context, "text.txt", destinationFile);
} catch (IOException e) {
e.printStackTrace();
}
}
}
private void copyStream(InputStream input, OutputStream output) throws IOException {
byte[] buffer = new byte[1024];
int length = Input.read(buffer);
while (length > 0) {
output.write(buffer, 0, length);
length = input.read(buffer);
}
}
private void copyFromAssetsToStorage(Context context, String sourceFile, String destinationFile) throws IOException {
InputStream inputStream = context.getAssets().open(sourceFile);
OutputStream outputStream = new FileOutputStream(destinationFile);
copyStream(inputStream , outputStream );
outputStream.flush();
outputStream.close();
inputStream.close();
}
I am assuming that this copies the file into the app's data directory. I have not been able to test it because I would like to be able to access the file using RandomAccessFile. However, I have never done either one of these two (copying the file from assets and RandomAccessFile) so I am stuck. The work on this app has come to a standstill because this is the only thing that is preventing me from completing it.
Can anyone provide me with corrections, suggestions, and correct implementations of how to access the data using RandomAccessFile? (The data is a list of strings 4-15 characters in length on each line.)
EDIT*
private File createCacheFile(Context context, String filename){
File cacheFile = new File(context.getCacheDir(), filename);
if (cacheFile.exists()) {
return cacheFile ;
}
InputStream inputStream = null;
FileOutputStream fileOutputStream = null;
try {
inputStream = context.getAssets().open(filename);
fileOutputStream = new FileOutputStream(cacheFile);
int bufferSize = 1024;
byte[] buffer = new byte[bufferSize];
int length = -1;
while ( (length = inputStream.read(buffer)) > 0) {
fileOutputStream.write(buffer,0,length);
}
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
finally {
try {
fileOutputStream.close();
} catch (IOException e) {
e.printStackTrace();
}
try {
inputStream.close();
} catch (IOException e) {
e.printStackTrace();
}
}
return cacheFile;
}

1- Copy the file from assets to the cache directory
This code just for illustration, you have to do appropriate exception handling and close resources
private File createCacheFile(Context context, String filename){
File cacheFile = new File(context.getCacheDir(), filename);
if (cacheFile.exists()) {
return cacheFile ;
}
InputStream inputStream = context.getAssets().open(filename);
FileOutputStream fileOutputStream = new FileOutputStream(cacheFile);
int bufferSize = 1024;
byte[] buffer = new byte[bufferSize];
int length = -1;
while ( (length = inputStream.read(buffer)) > 0) {
fileOutputStream.write(buffer,0,length);
}
fileOutputStream.close();
inputStream.close();
return cacheFile;
}
2- Open the file using RandomAccessFile
File cacheFile = createCacheFile(context, "text.txt");
RandomAccessFile randomAccessFile = new RandomAccessFile(cacheFile, "r");
// Process the file
randomAccessFile.close();
On a side note, you should follow Java naming conventions, e.g. your method and variable name should start with small letter such as copyFromAssetsToStorage and destinationFile
Edit:
You should make a separate try/catch for each close() operation, so if one fails the other still get executed and check that they are not null
finally {
try {
if(fileOutputStream!=null){
fileOutputStream.close();
}
} catch (IOException e) {
e.printStackTrace();
}
try {
if(inputStream!=null){
inputStream.close();
}
} catch (IOException e) {
e.printStackTrace();
}
}

Read file As String

I need to load an xml file as String in android so I can load it to TBXML xml parser library and parse it. The implementation I have now to read the file as String takes around 2seconds even for a very small xml file of some KBs. Is there any known fast method that can read a file as string in Java/Android?
This is the code I have now:
public static String readFileAsString(String filePath) {
String result = "";
File file = new File(filePath);
if ( file.exists() ) {
//byte[] buffer = new byte[(int) new File(filePath).length()];
FileInputStream fis = null;
try {
//f = new BufferedInputStream(new FileInputStream(filePath));
//f.read(buffer);
fis = new FileInputStream(file);
char current;
while (fis.available() > 0) {
current = (char) fis.read();
result = result + String.valueOf(current);
}
} catch (Exception e) {
Log.d("TourGuide", e.toString());
} finally {
if (fis != null)
try {
fis.close();
} catch (IOException ignored) {
}
}
//result = new String(buffer);
}
return result;
}

The code finally used is the following from:
http://www.java2s.com/Code/Java/File-Input-Output/ConvertInputStreamtoString.htm
public static String convertStreamToString(InputStream is) throws Exception {
BufferedReader reader = new BufferedReader(new InputStreamReader(is));
StringBuilder sb = new StringBuilder();
String line = null;
while ((line = reader.readLine()) != null) {
sb.append(line).append("\n");
}
reader.close();
return sb.toString();
}
public static String getStringFromFile (String filePath) throws Exception {
File fl = new File(filePath);
FileInputStream fin = new FileInputStream(fl);
String ret = convertStreamToString(fin);
//Make sure you close all streams.
fin.close();
return ret;
}

You can use org.apache.commons.io.IOUtils.toString(InputStream is, Charset chs) to do that.
e.g.
IOUtils.toString(context.getResources().openRawResource(<your_resource_id>), StandardCharsets.UTF_8)
For adding the correct library:
Add the following to your app/build.gradle file:
dependencies {
compile 'org.apache.directory.studio:org.apache.commons.io:2.4'
}
https://stackoverflow.com/a/33820307/1815624
or for the Maven repo see -> this link
For direct jar download see-> https://commons.apache.org/proper/commons-io/download_io.cgi

Reworked the method set originating from -> the accepted answer
#JaredRummler An answer to your comment:
Read file As String
Won't this add an extra new line at the end of the string?
To prevent having a newline added at the end you can use a Boolean value set during the first loop as you will in the code example Boolean firstLine
public static String convertStreamToString(InputStream is) throws IOException {
// http://www.java2s.com/Code/Java/File-Input-Output/ConvertInputStreamtoString.htm
BufferedReader reader = new BufferedReader(new InputStreamReader(is));
StringBuilder sb = new StringBuilder();
String line = null;
Boolean firstLine = true;
while ((line = reader.readLine()) != null) {
if(firstLine){
sb.append(line);
firstLine = false;
} else {
sb.append("\n").append(line);
}
}
reader.close();
return sb.toString();
}
public static String getStringFromFile (String filePath) throws IOException {
File fl = new File(filePath);
FileInputStream fin = new FileInputStream(fl);
String ret = convertStreamToString(fin);
//Make sure you close all streams.
fin.close();
return ret;
}

It's very easy if you use Kotlin:
val textFile = File(cacheDir, "/text_file.txt")
val allText = textFile.readText()
println(allText)
From readText() docs:
Gets the entire content of this file as a String using UTF-8 or
specified charset. This method is not recommended on huge files. It
has an internal limitation of 2 GB file size.

With files we know the size in advance, so just read it all at once!
String result;
File file = ...;
long length = file.length();
if (length < 1 || length > Integer.MAX_VALUE) {
result = "";
Log.w(TAG, "File is empty or huge: " + file);
} else {
try (FileReader in = new FileReader(file)) {
char[] content = new char[(int)length];
int numRead = in.read(content);
if (numRead != length) {
Log.e(TAG, "Incomplete read of " + file + ". Read chars " + numRead + " of " + length);
}
result = new String(content, 0, numRead);
}
catch (Exception ex) {
Log.e(TAG, "Failure reading " + this.file, ex);
result = "";
}
}

public static String readFileToString(String filePath) {
InputStream in = Test.class.getResourceAsStream(filePath);//filePath="/com/myproject/Sample.xml"
try {
return IOUtils.toString(in, StandardCharsets.UTF_8);
} catch (IOException e) {
logger.error("Failed to read the xml : ", e);
}
return null;
}

this is working for me
i use this path
String FILENAME_PATH = "/mnt/sdcard/Download/Version";
public static String getStringFromFile (String filePath) throws Exception {
File fl = new File(filePath);
FileInputStream fin = new FileInputStream(fl);
String ret = convertStreamToString(fin);
//Make sure you close all streams.
fin.close();
return ret;
}