Creating and Storing Log File on device in Android
Snapshot: 1
Fingerprint: 1, Rank: 0.23424, Boolean: true
Fingerprint: 2, Rank: 0.42344, Boolean: false
Fingerprint: 3, Rank: 0.23425, Boolean: true

Snapshot: 2
Fingerprint: 1, Rank: 0.75654, Boolean: false
Fingerprint: 2, Rank: 0.23456, Boolean: true
Fingerprint: 3, Rank: 0.89423, Boolean: true

................

File backupPath = Environment.getExternalStorageDirectory();

    backupPath = new File(backupPath.getPath() + "/Android/data/com.maximusdev.bankrecord/files");

    if(!fullPath.exists()){
        fullPath.mkdirs();
    }

    FileOutputStream fos;
    try {
        fos = new FileOutputStream(backupPath.getPath() + "/recordsbackup.txt");

        if(okaytowrite){
            for(int i = 0; i < count; ++i){
                entry = adapter.getItem(i);
                fos.write(entry.toString().getBytes());
                fos.write("n".getBytes());
                fos.write(String.valueOf(entry.dateTime).getBytes());
                fos.write("n".getBytes());
                fos.write(String.valueOf(entry.sign).getBytes());
                fos.write("n".getBytes());
                fos.write(String.valueOf(entry.cleared).getBytes());
                fos.write("n".getBytes());
                fos.write(String.valueOf(entry.transDate).getBytes());
                fos.write("n".getBytes());
                fos.write(entry.category.getBytes());
                fos.write("n".getBytes());
            }
        }
        fos.close();

        Toast.makeText(this, "Backup Complete", Toast.LENGTH_SHORT).show();

    } catch (FileNotFoundException e) {

        e.printStackTrace();

        AlertDialog.Builder delmessagebuilder = new AlertDialog.Builder(this);

        delmessagebuilder.setCancelable(false);

        delmessagebuilder.setMessage("File Access Error");

        delmessagebuilder.setNeutralButton("Okay", new DialogInterface.OnClickListener() {
            public void onClick(DialogInterface dialog, int id) {
                dialog.dismiss();
            }
        });

        delmessagebuilder.create().show();

    } catch (IOException e) {

        e.printStackTrace();

        AlertDialog.Builder delmessagebuilder = new AlertDialog.Builder(this);

        delmessagebuilder.setCancelable(false);

        delmessagebuilder.setMessage("File Access Error");

        delmessagebuilder.setNeutralButton("Okay", new DialogInterface.OnClickListener() {
            public void onClick(DialogInterface dialog, int id) {
                dialog.dismiss();
            }
        });

        delmessagebuilder.create().show();
    }

public static BufferedWriter out;
    private void createFileOnDevice(Boolean append) throws IOException {
            /*
             * Function to initially create the log file and it also writes the time of creation to file.
             */
            File Root = Environment.getExternalStorageDirectory();
            if(Root.canWrite()){
                 File  LogFile = new File(Root, "Log.txt");
                 FileWriter LogWriter = new FileWriter(LogFile, append);
                 out = new BufferedWriter(LogWriter);
                 Date date = new Date();
                 out.write("Logged at" + String.valueOf(date.getHours() + ":" + date.getMinutes() + ":" + date.getSeconds() + "n"));
            }
        }

public void writeToFile(String message){
        try {
            out.write(message+"n");
        } catch (IOException e) {
            e.printStackTrace();
        }