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androidandroid-studionullpointerexceptionandroid-assets

How to read a text file from assets in Android Studio?


I have may wifi2.txt file in my assets file directory in Android Studio. However, I keep getting a NULLPointException when I try to access it. My code is below: (Thanks so much in advance) enter image description here

             //CSV FILE READING
    File file = null;



    try {



        FileInputStream is = new FileInputStream(file);

        try {
            BufferedReader reader = new BufferedReader(new InputStreamReader(getAssets().open("wifi2.txt")));
            String line;
            Log.e("Reader Stuff",reader.readLine());
            while ((line = reader.readLine()) != null) {
                Log.e("code",line);
                String[] RowData = line.split(",");
                LatLng centerXY = new LatLng(Double.valueOf(RowData[1]), Double.valueOf(RowData[2]));
                if (RowData.length == 4) {
                    mMap.addMarker(new MarkerOptions().position(centerXY).title(String.valueOf(RowData[0]) + String.valueOf(RowData[3])).icon(BitmapDescriptorFactory.defaultMarker(BitmapDescriptorFactory.HUE_GREEN)));
                }

            }

        } catch (IOException ex) {
           ex.printStackTrace();
        } finally {
            try {
                is.close();
            } catch (IOException e) {
               e.printStackTrace();
            }
        }
    } catch (FileNotFoundException e) {
        e.printStackTrace();
    }


   //Done with CSV File Reading

Solution

  • File file = null;
    try {
        FileInputStream is = new FileInputStream(file);
    

    Actually you are not using FileInputStream anywhere. Just use this piece of code

      try {
            BufferedReader reader = new BufferedReader(new InputStreamReader(getAssets().open("wifi2.txt")));
            String line;
            Log.e("Reader Stuff",reader.readLine());
            while ((line = reader.readLine()) != null) {
                Log.e("code",line);
                String[] RowData = line.split(",");
                LatLng centerXY = new LatLng(Double.valueOf(RowData[1]), Double.valueOf(RowData[2]));
                if (RowData.length == 4) {
                    mMap.addMarker(new MarkerOptions().position(centerXY).title(String.valueOf(RowData[0]) + String.valueOf(RowData[3])).icon(BitmapDescriptorFactory.defaultMarker(BitmapDescriptorFactory.HUE_GREEN)));
                }
    
            }
    
        } catch (IOException ex) {
           ex.printStackTrace();
        }