Q:

Releasing resources acquired by BufferedReader, InputStreamReader and InputStream

I've got the following piece of code:
public ArrayList<Crime> loadCrimes() throws IOException, JSONException {
    ArrayList<Crime> crimes = new ArrayList<Crime>();
    BufferedReader reader = null;
    try {
        // Open and read the file into a StringBuilder
        InputStream in = mContext.openFileInput(mFilename);
        //what if an exception gets thrown in the line below?
        reader = new BufferedReader(new InputStreamReader(in));
        StringBuilder jsonString = new StringBuilder();
        String line = null;
        while ((line = reader.readLine()) != null) {
            // Line breaks are omitted and irrelevant
            jsonString.append(line);
        }
        // Parse the JSON using JSONTokener
        JSONArray array = (JSONArray) new JSONTokener(jsonString.toString()).nextValue();
        // Build the array of crimes from JSONObjects
        for (int i = 0; i < array.length(); i++) {
            crimes.add(new Crime(array.getJSONObject(i)));
        }
    } catch (FileNotFoundException e) {
        // Ignore this one; it happens when starting fresh
    } finally {
        if (reader != null)
            reader.close();
        }
    return crimes;
}

First, I wondered why we call .close() just on the BufferedReader object and not on the InputStream and InputStreamReader objects. I checked the official Oracle documentation and skimmed through a couple of questions in stackoverflow and according to what I've read BufferedReader.close() takes care of releasing the resources acquired by InputStreamReader and InputStream, so I don't have to call .close() on them.
Is this correct?
Secondly, I thought what would happen if an exception got thrown after creating the InputStream object and before creating the BufferedReader object. That is, either the InputStreamReader(InputStream in) constructor or BufferedReader(Reader in) constructor throws an exception. In that case we have acquired a file resource with InputStream but the BufferedReader object is still null, so in the finally block, the .close() method will not be invoked and the InputStream will not release the resources it has acquired.
Then I read the Oracle documentation, and neither of those two constructors throw an exception according to it. So it's not possible for an exception to occur between those two lines, right?
My final question is "Does this piece of code make sure it releases all resources it acquires?"

A:

First, I wondered why we call .close() just on the BufferedReader object and not on the InputStream and InputStreamReader objects. I checked the official Oracle documentation and skimmed through a couple of questions in stackoverflow and according to what I've read BufferedReader.close() takes care of releasing the resources acquired by InputStreamReader and InputStream, so I don't have to call .close() on them.
  Is this correct?

Yes, it is.

My final question is "Does this piece of code make sure it releases all resources it acquires?"

Most probably, yes. Even if some odd exceptions occur when creating the InputStreamReader or the BufferedReader, after exiting the block where they're defined, before GC collects them, they will be automatically closed as well. Of course, it's usually not a good idea to count on the GC to cleanup for you so if you want to be 100% sure, you might want to do it yourself in the finally block.
Another easier way is to use a FileReader which will simplify the code by only using two objects: 
BufferedReader reader = new BufferedReader(new FileReader(fileName));

(I am assuming you want to read from a file).

