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How to find a path write to a json file in Android studio emulation?

I am trying use Android Studio emulation to produce a json in my apps. Is there a way to locate the directory and set it as path and implement it in the following?
......
DIRECTORY directory = createDummySchool();
ObjectMapper mapper = new ObjectMapper();
try {
mapper.writeValue(new File(filepath? + "sample.json"), directory);
}catch (IOException e) {
e.printStackTrace();}
.....

well it depends where you want to write your file in, Internal or external memory.
you can always write information in internal memory which can be accessible by your app but to write on external memory you will require permission like
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
To save file internally you can use this
getFilesDir();
String filename = "myfile";
File file = new File(context.getFilesDir(), filename);
String string = "Hello world!";
FileOutputStream outputStream;
try {
outputStream = openFileOutput(filename, Context.MODE_PRIVATE);
outputStream.write(string.getBytes());
outputStream.close();
} catch (Exception e) {
e.printStackTrace();
}
refer this for more information, this is the best way and should be the first place where you should be looking, :)

Create file in specified directory

Try to create file in specific directory but it shows the error FileNotFound. Why?
Am I using impossible path? I really don't know, but is seems like the code should be working.
String day=/1;
String zn="/zn";
File_name=zn
String root= Environment.getExternalStorageDirectory().toString();
File_path=root+day;
File file1 = new File(File_path,File_name);
file1.mkdirs();
if(!file1.exists()) {
try {
file1.createNewFile();
} catch (IOException e) {
e.printStackTrace();
}
}
try {
OutputStream fos= new FileOutputStream(file1);
String l,d,p;
l = lessnum.getText().toString();
d = desc.getText().toString();
p = place.getText().toString();
fos.write(l.getBytes());
fos.write(d.getBytes());
fos.write(p.getBytes());
fos.close();

Change your code as for creating a file on sdcard
String root= Environment.getExternalStorageDirectory().getAbsolutePath();
String File_name = "File_name.Any_file_Extension(like txt,png etc)";
File file1 = new File(root+ File.separator + File_name);
if(!file1.exists()) {
try {
file1.createNewFile();
} catch (IOException e) {
e.printStackTrace();
}
}
In current you you are also missing file Extension with file name so change String zn as zn="/zn.txt";
and make sure you have added Sd card permission in AndroidManifest.xml :
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>

First you make a directory
String root= Environment.getExternalStorageDirectory().toString();
String dirName =
root+ "abc/123/xy";
File newFile = new File(dirName);
newFile.mkdirs();
then you create a file inside that directory
String testFile = "test.txt";
File file1 = new File(dirName,testFile);
if(!file1.exists()){
try {
file1.createNewFile();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
then do your file writing operations
try { OutputStream fos= new FileOutputStream(file1);
String l,d,p;
l = lessnum.getText().toString();
d = desc.getText().toString();
p = place.getText().toString();
os.write(l.getBytes());
fos.write(d.getBytes());
fos.write(p.getBytes());
fos.close();
}
catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
I think this will help you...
Thanks...

you will need to give your app the correct permission to write to the SD Card by adding the line below to your Manifest:
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
And check http://developer.android.com/reference/android/os/Environment.html#getExternalStorageDirectory%28%29

String root= Environment.getExternalStorageDirectory().toString();
String dirName =
root+ "abc/123/xy";
File newFile = new File(dirName);
newFile.mkdirs();
String testFile = "test.txt";
File file1 = new File(dirName,testFile);
if(!file1.exists()){
try {
file1.createNewFile();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
And and <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>
on manifest file...
Thanks...

Here is your latest attempt:
File_path = root + File.separator + day;
File f_dir = new File(File_path);
f_dir.mkdirs();
File file1 = new File(f_dir, File_name);
if (!file1.exists()) {
try {
file1.createNewFile();
} catch (IOException e) {
e.printStackTrace();
}
}
try {
OutputStream fos= new FileOutputStream(file1);
If you showed us the complete stacktrace and error message it would be easier to figure out what is going wrong, but I can think of a couple of possibilities:
You are not checking the value returned by f_dir.mkdirs(), and it could well be returning false to indicate that the directory path was not created. This could mean that:
The directory already existed.
Something existed but it wasn't a directory.
Some part of the directory path could not be created ... for one of a number of possible reasons.
The file1.exists() call will return true if anything exists with that pathname given by the object. The fact that something exists doesn't necessarily mean that you can open it for writing:
It could be a directory.
It could be a file that the application doesn't have write permissions for.
It could be a file on a read-only file system.
And a few other things.
If I was writing this, I'd write it something like this:
File dir = new File(new File(root), day);
if (!dir.exists()) {
if (!dir.mkdirs()) {
System.err.println("Cannot create directories");
return;
}
}
File file1 = new File(dir, fileName);
try (OutputStream fos= new FileOutputStream(file1)) {
...
} catch (FileNotFoundException ex) {
System.err.println("Cannot open file: " + ex.getMessage());
}
I only attempt to create the directory if required ... and check that the creation succeeded.
Then I simply attempt to open the file to write to it. If the file doesn't exist it will be created. If it cannot be created, then the FileNotFoundException message should explain why.
Notice that I've also corrected the style errors you made in your choice of variable names.

Android File not created on SD card

I'm trying to create a file on the SD on my device. This worked a week ago, but now it isn't, and I don't understand why.
The Logcat prints:
java.io.FileNotFoundException ...pathtofile... (no such file or directory)
So, the file is not being created. I have the correct permissions on the android manifest:
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"></uses-permission>
I create the file this way:
if (Environment.getExternalStorageState().equals(Environment.MEDIA_MOUNTED)){
base = Environment.getExternalStorageDirectory().getAbsolutePath();
}
String fname = File.separator +"VID_"+ timeStamp + ".3gp";
mediaFile = new File(base+fname);
Then I check if it exists:
if(mediaFile.exists()){
Log.v("mediaFile","ex");
}else{
Log.v("mediaFile","no ex");
}
And the log says that IT DOESN'T EXIST. I also have tried with file.createNewFile() and it doesn't work.
So, a week ago it was working, now it doesn't work, it could be a problem with the SD card ???? Could it be some type of BUG!!!????
Thanks
EDIT: More Code
The function where the file is created is :
private static File getOutputMediaFile()
Called from:
private static Uri getOutputMediaFileUri(){
return Uri.fromFile(getOutputMediaFile());
}
And setted to mediarecorder output as:
vMediaRecorder.setOutputFile(getOutputMediaFileUri().toString());
So, when I do mediarecorder.prepare():
try {
vMediaRecorder.prepare();
} catch (IllegalStateException e) {
Log.v("RELEASE VIDREC1",e.toString());
releaseMediaRecorder();
return false;
} **catch (IOException e) {
Log.v("RELEASE VIDREC2",e.toString());
releaseMediaRecorder();
return false;**
}
The bold catch is the one that runs, and prints:
java.io.FileNotFoundException ...pathtofile... (no such file or directory)

just try this
String fname = "VID_"+ timeStamp + ".3gp";
if (Environment.getExternalStorageState().equals(Environment.MEDIA_MOUNTED))
{
mediaFile = new File(android.os.Environment.getExternalStorageDirectory(),fname);
if(!mediaFile.exists())
{
mediaFile.createNewFile();
}
}
if(mediaFile.exists()){
Log.v("mediaFile","ex");
}else{
Log.v("mediaFile","no ex");
}

You merely create the object mediaFile, not the actual file. Use this:
if(!f.exists()){
f.createNewFile();
}
I tried this, for me it works.
final String filename = "file.3gp";
final String path = Environment.getExternalStorageDirectory() + "/" + filename;
File outputfile = new File(path);
if (!outputfile.exists()) {
try {
outputfile.createNewFile();
}
catch (IOException e) {
e.printStackTrace();
}
}
MediaRecorder recorder = new MediaRecorder();
recorder.setAudioSource(MediaRecorder.AudioSource.MIC);
recorder.setOutputFormat(MediaRecorder.OutputFormat.THREE_GPP);
recorder.setAudioEncoder(MediaRecorder.AudioEncoder.AMR_NB);
recorder.setOutputFile(outputfile.toString());
try {
recorder.prepare();
recorder.start();
/*recorder.stop();
recorder.reset();
recorder.release();*/
}
catch (IllegalStateException e) {
e.printStackTrace();
}
catch (IOException e) {
e.printStackTrace();
}
Try and see whether or not it works. If not, can you add the full code of getOutputMediaFile()?

My answer here:
First open the path, then add the file:
String dir = Environment.getExternalStorageDirectory(); // getAbsolutePath is not requried
File path = new File(dir);
File root = new File(path, "VID_"+ timeStamp + ".3gp";);

Thanks for your help, I've solved the problem using old code. It is strange because the "file saving" part has no modification. Thanks for all guys, kinda.

Where will be a file created in android if I do it like this

This function creates a file but I can't figure out where is the file created and if someone has a solution to create a file in a particular directory from the external storage is very welcomed :) thanks a lot
private void writeFileToInternalStorage() {
String eol = System.getProperty("line.separator");
BufferedWriter writer = null;
try {
writer = new BufferedWriter(new OutputStreamWriter(openFileOutput("myfile", MODE_WORLD_WRITEABLE)));
writer.write("This is a test1." + eol);
writer.write("This is a test2." + eol);
} catch (Exception e) {
e.printStackTrace();
} finally {
if (writer != null) {
try {
writer.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
}

for query
Where will be a file created
it will create in Internal Storage as function name said and that will be like
/data/data/yourApp_package_as_in_manifest/ (can see in DDMS)
for query
if someone has a solution to create a file in a particular directory
from the external storage is very welcomed
as per link Write a file in external storage in Android
.........
** Method to check whether external media available and writable. This is adapted from
http://developer.android.com/guide/topics/data/data-storage.html#filesExternal */
private void checkExternalMedia(){
boolean mExternalStorageAvailable = false;
boolean mExternalStorageWriteable = false;
String state = Environment.getExternalStorageState();
if (Environment.MEDIA_MOUNTED.equals(state)) {
// Can read and write the media
mExternalStorageAvailable = mExternalStorageWriteable = true;
} else if (Environment.MEDIA_MOUNTED_READ_ONLY.equals(state)) {
// Can only read the media
mExternalStorageAvailable = true;
mExternalStorageWriteable = false;
} else {
// Can't read or write
mExternalStorageAvailable = mExternalStorageWriteable = false;
}
tv.append("\n\nExternal Media: readable="
+mExternalStorageAvailable+" writable="+mExternalStorageWriteable);
}
/** Method to write ascii text characters to file on SD card. Note that you must add a
WRITE_EXTERNAL_STORAGE permission to the manifest file or this method will throw
a FileNotFound Exception because you won't have write permission. */
private void writeToSDFile(){
// Find the root of the external storage.
// See http://developer.android.com/guide/topics/data/data- storage.html#filesExternal
File root = android.os.Environment.getExternalStorageDirectory();
tv.append("\nExternal file system root: "+root);
// See https://stackoverflow.com/questions/3551821/android-write-to-sd-card-folder
File dir = new File (root.getAbsolutePath() + "/download");
dir.mkdirs();
File file = new File(dir, "myData.txt");
try {
FileOutputStream f = new FileOutputStream(file);
PrintWriter pw = new PrintWriter(f);
pw.println("Hi , How are you");
pw.println("Hello");
pw.flush();
pw.close();
f.close();
} catch (FileNotFoundException e) {
e.printStackTrace();
Log.i(TAG, "******* File not found. Did you" +
" add a WRITE_EXTERNAL_STORAGE permission to the manifest?");
} catch (IOException e) {
e.printStackTrace();
}
tv.append("\n\nFile written to "+file);
}
and also add a WRITE_EXTERNAL_STORAGE permission to the manifest

It will be created on internal folder: /data/data/com.package.name/ You cannot access that folder using file browser.
If you want to easily access the file you can try to create it on SD card:
/*...*/
String baseDir = Environment.getExternalStorageDirectory().getAbsolutePath();
String fileName = baseDir + "/"+ "myFile.txt";
FileOutputStream writer = null;
try {
writer = new FileOutputStream(fileName);
writer.write("This is a test1." + eol);
/*...*/

Writing a file to sdcard

I'm trying to write a file from an Http post reply to a file on the sdcard. Everything works fine until the byte array of data is retrieved.
I've tried setting WRITE_EXTERNAL_STORAGE permission in the manifest
and tried many different combinations of tutorials I found on the net.
All I could find was using the openFileOutput("",MODE_WORLD_READABLE) method, of the activity but how my app writes file is by using a thread. Specifically, a thread is invoked from another thread when a file has to be written,
so giving an activity object didn't work even though I tried it.
The app has come a long way and I cannot change how the app is currently written.
Please, someone help me?
CODE:
File file = new File(bgdmanip.savLocation);
FileOutputStream filecon = null;
filecon = new FileOutputStream(file);
byte[] myByte;
myByte = Base64Coder.decode(seReply);
bos.write(myByte);
filecon.write(myByte);
myvals = x * 11024;
bgdmanip.savLocation holds the whole files path. seReply is a string reply from HttpPost response. The second set of code is looped with reference to x. The file is created but remains 0 bytes.

//------------------------------WRITING DATA TO THE FILE ---------------------------------
btnWriteSDFile.setOnClickListener(new OnClickListener()
{
public void onClick(View v)
{
try {
File myFile = new File("/sdcard/mysdfile.txt");
myFile.createNewFile();
FileOutputStream fOut = new FileOutputStream(myFile);
OutputStreamWriter myOutWriter =new OutputStreamWriter(fOut);
myOutWriter.append(txtData.getText());
myOutWriter.close();
fOut.close();
Toast.makeText(v.getContext(),"Done writing SD 'mysdfile.txt'", Toast.LENGTH_SHORT).show();
txtData.setText("");
}
catch (Exception e)
{
Toast.makeText(v.getContext(), e.getMessage(),Toast.LENGTH_SHORT).show();
}
}
});
//---------------------------READING DATA FROM THE FILE PLACED IN SDCARD-------------------//
btnReadSDFile.setOnClickListener(new OnClickListener()
{
public void onClick(View v)
{
try {
File myFile = new File("/sdcard/mysdfile.txt");
FileInputStream fIn = new FileInputStream(myFile);
BufferedReader myReader = new BufferedReader(new InputStreamReader(fIn));
String aDataRow = "";
String aBuffer = "";
while ((aDataRow = myReader.readLine()) != null)
{
aBuffer += aDataRow ;
}
txtData.setText(aBuffer);
myReader.close();
Toast.makeText(v.getContext(),"Done reading SD 'mysdfile.txt'",Toast.LENGTH_SHORT).show();
}
catch (Exception e)
{
Toast.makeText(v.getContext(), e.getMessage(),Toast.LENGTH_SHORT).show();
}
}
});
ALONG WITH THIS ALSO WRITE THIS PERMISSION IN Android.Manifest
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />

The openFileOutput() method writes data to your application's private data area (not the SD card), so that's probably not what you want. You should be able to call Environment.getExternalStorageDirectory() to get the root path to the SD card and use that to create a FileOutputStream. From there, just use the standard java.io routines.

Here is a sample:
// Log used as debug
File log = new File(Environment.getExternalStorageDirectory(), "Log.txt");
try {
out = new BufferedWriter(new FileWriter(log.getAbsolutePath(), false));
out.write(new Date().toString());
out.write(" : \n");
} catch (Exception e) {
Log.e(TAG, "Error opening Log.", e);
}