Convert and add list of string to set of ID?

Question

I am tring to add list of string to set of Id . i am trying to avoid one more for loop to again loop and convert using Id.valueOf(). Help me to achieve it.

Map<String,Set<String>> delegationDataMap // Value retrieved from some other function call 
Set<Id> permSetIds = new Set<Id>();
for (List<String> permSetSubSet : delegationDataMap.values()){
    permSetIds.add((Set<Id>)permSetSubSet);// Struggling here
}

Thank you all .I found answer from this article

for(Set<String> permSetSubSet : delegationDataMap.values()){            
    permSetIds.addAll(new Set<Id>((List<Id>)new List<String>(permSetSubSet)));
}

Now what is the most efficient way of this conversion. will JSON step ahead of this ?

Answer 1

JSON is a CPU hog; you may as well loop over your Set and cast each element individually at that point. You should not use JSON for converting a list to a set or vice versa. As an aside, you're also abusing a compiler bug by casting a List<String> to a List<Id>. You should be prepared for runtime exceptions if you do this. Realistically, you should fix the delegationDataMap to be Map<String, Set<Id>> if it really is meant to be a set of Id values.

Answer 2

You could use related good solution answered by Peter Knolle.

Here is an example based on your code:

Map<String, Set<String>> mapOfSet = new Map<String, Set<String>>{
    'a' => new Set<String> {'Id 1', ..},
    'b' => new Set<String> {'Id2', ..}
};
Set<Id> setOfId = new Set<Id>();
for(Set<String> s: mapOfSet.values()) {
    setOfId.addAll((Set<Id>) JSON.deserialize(JSON.serialize(s), Set<Id>.class));
}

System.debug('==' + setOfId);

Answer 3

You can use JSON class for this:

Map<String,Set<String>> delegationDataMap // Value retrieved from some other function call 
Set<Id> permSetIds = new Set<Id>();
for (List<String> permSetSubSet : delegationDataMap.values()){
    permSetIds.addAll((Set<Id>)JSON.deserialize(JSON.serialize(permSetSubSet), Set<Id>.class));
}

Answer 4

As much as I love clever solutions, I think in this case you will get the best readability and maintainability by just doing a normal loop (plus it gives you better error handling):

Map<String,Set<String>> delegationDataMap;
Set<Id> permSetIds = new Set<Id>();
for (List<String> permSetSubSet : delegationDataMap.values())
{
    for(String element : permSetSubSet)
    {
        if (element instanceof ID)
        {
            permSetIds.add(element);
        }
        else
        {
            System.debug('Attempted to add invalid ID: ' + element);
        }
    }
}