BufferedReader br = new BufferedReader(new InputStreamReader(new ByteArrayInputStream(buf1)));
         while (true) {
            String referenceLine = br.readLine(); // of the normal reader
            if (referenceLine == null) 
               break;
            String lineToCheck = bism.readLine(); // must be the same as the corresponding reference since we expect same behaviour
            if (lineToCheck == null) 
               assertTrue("the line to be checked is unexpectedly null", false);
            assertEquals("wrong content", referenceLine, lineToCheck);
         }