Java 8 Stream to find element in list

Question

I have the following class:

public class Item {
    int id;
    String name;
    // few other fields, contructor, getters and setters
}

I have

Answer 1

You want to find at most one item for each given id and do something with the found item, right? A bit more performance improvement:

Set idsToLookup = new HashSet<>(getIdsToLookup()); // replace list with Set

items.stream()
    .filter(e -> idsToLookup.remove(e.getId()))
    .forEach(
       /* doing something */
     );