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Java

Isaias Valdez
Isaias Valdez
1,412 Points
Posted by Isaias Valdez
Isaias Valdez
1,412 Points

Help me understand Map<String, List<Song>> byArtist = new HashMap<>();

How does a List of Song objects, with each Song having 3 string values (artist, title, video url) get stored as a single value in a Map? Isn't a Map key only allowed to map to at most one value? Song object has 3 values (mArtist, mTitle, mVideoUrl). How are we able to have a List of Songs as a Map value?

1 Answer

Steven Parker
Steven Parker
231,261 Points
Steven Parker
Steven Parker
231,261 Points

A "Song" object may have multiple properties, but it's still one object. And you can put several objects into a list, but the list itself is one thing.

And you're right that a map key can only be associated with one value, but the single value can be a list.