Some Map implementations are allowed to have null values, eg HashMap, in this case if get(key) returns null it does not guarantee that there is no entry in the map associated with this key. So if you want to know if a map contains a key use Map.containsKey. If you simply need a value mapped … Read more
Yes. If the computer doesn’t run it, it’s broken. If people can’t read it, it will be broken. Soon.
Exceptions are not conditionals. The conditional version is clearer. That’s natural: this is straightforward flow control, which is what conditionals are designed for, not exceptions. The exception version is primarily used as an optimization when doing these lookups in a loop: for some algorithms it allows eliminating tests from inner loops. It doesn’t have that … Read more
[y for y in (f(x) for x in l) if y] Will do.
You could possibly use a dictionary. Dictionaries store references, which means functions are perfectly viable to use, like so: operationFuncs = { Operation.START: strategy_objects.StartObject Operation.STOP: strategy_objects.StopObject Operation.STATUS: strategy_objects.StatusObject (…) } It’s good to have a default operation just in case, so when you run it use a try except and handle the exception (ie. the … Read more
I’ve always used if (“true”.equals(object.getAttribute(“someAttr”))) { // …. because although it is a little more difficult to read it’s much less verbose and I think it’s readable enough so you get used to it very easily