java - How to make a new list with a property of an object which is in another list - Stack Overflow

java - How to make a new list with a property of an object which is in another list - Stack Overflow

ists.transform(studentList, StudentToId.INSTANCE);

Surely it will loop in order to extract all ids, but remember guava methods returns view and Function will only be applied when you try to iterate over the List<Integer>
If you don't iterate, it will never apply the loop.

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