In java, List and Map are using in collections. But i couldn’t understand at which situations we should use List and which time use Map. What is the major difference between both of them?
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In java, List and Map are using in collections. But i couldn’t understand at which situations we should use List and which time use Map. What is the major difference between both of them?
Now would be a good time to read the Java collections tutorial – but fundamentally, a list is an ordered sequence of elements which you can access by index, and a map is a usually unordered mapping from keys to values. (Some maps preserve insertion order, but that’s implementation-specific.)
It’s usually fairly obvious when you want a key/value mapping and when you just want a collection of elements. It becomes less clear if the key is part of the value, but you want to be able to get at an item by that key efficiently. That’s still a good use case for a map, even though in some senses you don’t have a separate collection of keys.
There’s also
Set, which is a (usually unordered) collection of distinct elements.