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Java Java Data Structures - Retired Exploring the Java Collection Framework Sets

Posted by Dinu Comendant
Dinu Comendant
6,049 Points

add vs addAll

I don't quite understand what's the difference between these two, since when we do a for loop, we should get the same results, regardless if we use add or addAll.

1 Answer

Steven Parker
Steven Parker
231,275 Points
Steven Parker
Steven Parker
231,275 Points

The difference is that you use a loop and "add" together to add one item at a time.

But when you use "addAll" you add an entire collection at once and you don't need a loop.