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Java Java Data Structures - Retired Efficiency! Implement Chooser UI

Posted by edard stark
edard stark
272 Points

why he used List<Song>

please explain me Thank you!

Simon Coates
Simon Coates
28,694 Points
Simon Coates
Simon Coates
28,694 Points

List is just an flexible sized ordered collection. It's very common for wanting to bundle multiple objects into a single variable and has more flexibility than an array. You can read List<Song> as "list of songs". Being an interface, it just defines the methods that the implementing classes (eg. ArrayList) needs to implement. The motivation for using the List over a concrete implementation is increased abstraction (helps with maintenance). The list defines the contract, and given that all lists have a minimal set of methods defined by the interface, you could plausibly replace the type of underlying implementation (maybe using a LinkedList over an ArrayList).

Song is a custom class used to bundle some data and behavior for ease of use and conceptual clarity.