Using Mockito for HTTP Client

I have a stubbed JSON OBJECT but need to mock the following using Mockito:

HttpResponse response = defaultHttpClient.execute(postRequest);
BufferedReader rd = new BufferedReader(new InputStreamReader(response.getEntity().getContent()));
StringBuilder result = new StringBuilder();
while ((line = rd.readLine()) != null) {
    result.append(line);        
}
JSONObject jsonResponseObject = new JSONObject(result.toString()); 

I have created the following Mocks:

@Mock
    private HttpClient mockHttpClient;
    private HttpPost mockHttpPost;
    private HttpResponse mockHttpResponse;
    private HttpEntity mockHttpEntity; 
    private InputStream mockInputStream;
    private InputStreamReader mockInputStreamReader;
    private BufferedReader mockBufferedReader;

And have the following when statements:

    Mockito.when(mockHttpClient.execute(mockHttpPost)).thenReturn(mockHttpResponse); 
    Mockito.when(mockHttpResponse.getEntity()).thenReturn(mockHttpEntity);
    Mockito.when(mockHttpEntity.getContent()).thenReturn(mockInputStream);

Question: Do I need to create all these 'when' statements and if yes then which other ones do I need to create to be able to get to the stubbed JSON?

Any suggestions pls?

Thanks