@Override
protected T doInBackground(Void... params) {
long startTime, endTime;
T result = null;
try {
startTime = System.currentTimeMillis();
result = calculus.perform();
endTime = System.currentTimeMillis();
elapsedTime = endTime - startTime;
return result;
} catch (Exception e) {
callback.ifFails(e);
}
return result;
}
