What are some common usage scenarios for Java collections?

What are some common usage scenarios for Java collections?

Java collections are used in various scenarios, such as storing lists of items, managing sets of unique elements, and mapping keys to values.

Can you give me an example of when to use an ArrayList?

Sure! Use an ArrayList when you need a resizable array that allows for fast random access and frequent additions/removals.

What about when to use a HashMap?

A HashMap is ideal when you need to associate keys with values and require fast lookups, insertions, and deletions.

Are there any performance considerations I should be aware of?

Yes, different collections have varying performance characteristics. For example, ArrayLists are faster for indexed access, while LinkedLists are better for frequent insertions and deletions.