working .dat extension file in android - android

I need to use a file of type .dat in Android, but I cannot reference to the file ,application doesnt realize that file
Is that code correct?
File sdcard=Environment.getExternalStorageDirectory();
File file=new File(sdcard,"dictionary.dat");
if(file.exists()){
Toast.makeText(context,"file exists",Toast.LENGTH_LONG).show();
}
else{
Toast.makeText(context,"NOT exists",Toast.LENGTH_LONG).show();
}
String path=file.getAbsolutePath();
FileInputStream fis=new FileInputStream(path);
DataInputStream dawgDataFile=new DataInputStream(fis);
maybe I coded in wrong way, I just need to use "dictionary.dat" file , and I have stored it in raw folder. Button application says "NOT exists" . help please

you cannot get a file saved in RAW folder like that. This is how you can do it:
InputStream inputStream = getResources().openRawResource(R.raw.dictionary);
BufferedReader reader = new BufferedReader(new InputStreamReader(inputStream));
//then start reading lines from reader with reader.readLine()
P.S. when saving files in RAW folder, file extensions can be omitted as they are not available when referencing in code

Related

Open a file from SD card in android

To open a file from android application asset folder I used below code:
InputStream fis = getApplicationContext().getAssets().open(filename);
Same thing I want to open a file from SDcard... How to do?
File file = new File(path);
InputStream in = new FileInputStream(file);
This should work as long as the sdcard is mounted with a valid path.

can't find file created in dir returned by getFilesDir()

One part of my app needs to write a data file out.
I use getFilesDir() and it gives me a path like this (after adding a file name):
/data/data/com.casadelgato.zillaconfigdroid/files/Log.1378357559316.csv
I create a PrintWriter to the file, write a bunch of stuff to it, and close it.
No errors.
The problem is that I can't find the file anywhere on my Android device.
mention the file name in the path
FileOutputStream fos = context.openFileOutput(path,
Context.MODE_PRIVATE);
write the file into the stream...and you get the file by passing the same file name
FileInputStream openFileInput = context.openFileInput(path);
read the input stream

Unable to read file from the Downloads folder for an android app

I want to create an inputstream for a file that is stored in the Downloads folder of my phone.
Earlier I had the required file as an asset and I read it with this code:
InputStream fin;
fin = getAssets().open(FILENAME);
However now I want to be able to open a file stored in my downloads folder /mnt/sdcard/Download as an InputStream NOT as a FileInputStream Object. I am using a library which requires an InputStream only as an argument so I can not use the FileInputStream
methods because I get a fatal exception if I do and the App stops.
How do I go about this? I tried to find some helper function from the documentation, but could not.
Edit: I also tried editing the code to this-
String path = "/mnt/sdcard/Download"+FILENAME;
fin = new BufferedInputStream(new FileInputStream(path));
However still when I try to read the file, the App crashes.
I had the same issue as yours :
AssetManager am=getAssets();
InputStream is=am.open("file1.xls");
InputStream is = new FileInputStream(filepath);
Workbook wb = Workbook.getWorkbook(is);
Here I used to access file1.xls from the assets folder.
I fixed it by using :
File filepath = newFile(Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_DOWNLOADS)+"/"+"file1.xls"); // fist part gets the directory of download folder and last part is your file name
InputStream is = new FileInputStream(filepath);
Workbook wb = Workbook.getWorkbook(is);
Don't forget to get the storage permission first to access the storage.

how to create .json file and how to write json object into json file ...In android

I am using this code for creating the new file and write the json object in test.json file but I am unable to create file.Please find mistake and give the best result
One things I have also write the code for permission in manifest file..
Thanks,
String fileName = "test";
File file = new File("/data/data/packagename/test.json");
file.createNewFile();
DataOutputStream fos = new DataOutputStream(openFileOutput(fileName , Context.MODE_PRIVATE));
if(file.exists()){
fos.write(jsString.getBytes());
fos.close();
}
This will not land on C:/ anyway. At best at your SD card or some other folder, and since android is a unix based system. you should be careful on how you use "slashes"

How do I store files on an android phone?

When creating an Android application, I have some files that needs to be stored on the android itself.
How do I do this?
If you have local files, like some error tones, some openning video.. then place it in you assets folder of your project.
If you have dynamic data need to download at run time then use this guide.
Best place for generic files would be the assets folder.
You can access files through the AssetManager, which you can get with Activity.getAssets() for example.
Here is an example how you could access a text file:
try {
BufferedReader br = new BufferedReader(
new InputStreamReader(getAssets().open("sometextfile.txt")));
// do stuff with br
} catch (IOException e) {
e.printStackTrace();
}
For more information on AssetManager read the Java Doc. Oh and yes, you can create folders in assets.
If you want to keep some files like readme.txt or even music files, you can use the raw folder inside of res folder. So create a folder named raw inside of res folder.
Inside of raw folder, let us assume that there is a file named readme.txt, assuming that the Activity class is called MyActivity.
Now, you can read the contents of a file into a String as shown below:
StringBuilder strContents = new StringBuilder();
String thisLine;
InputStream is = MyActivity.this.getResources().openRawResource(R.raw.readme);
InputStreamReader isr = new InputStreamReader(is);
BufferedReader br = new BufferedReader(isr);
while ((thisLine = br.readLine()) != null) { // while loop begins here
strContents.append(thisLine);
}
br.close();
//Now you have the data in strContents
Alternately, assets is also one such folder that you can use since the raw folder contains the file as is without any optimization, zipping done by Android.
So create an assets folder in your Project root folder and place your files there e.g. myfile.
Now, you can get an instance of the file InputStream as given below:
InputStream is = getBaseContext().getAssets().open("mydb");

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