What are the best practices for using ArrayLists in Java?

What are the best practices for using ArrayLists in Java?

When using ArrayLists in Java, consider the following best practices: 1. Initialize with a capacity if you know the size in advance. 2. Use generics to avoid type casting. 3. Prefer ArrayList over LinkedList for random access. 4. Be cautious with resizing, as it can be costly.

Why should I use generics with ArrayLists?

Using generics with ArrayLists helps ensure type safety, preventing runtime errors by allowing you to specify the type of elements the list will hold.

What happens if I don't initialize the capacity?

If you don't initialize the capacity, the ArrayList will start with a default size and resize as needed, which can lead to performance overhead due to frequent resizing.

Can you give an example of initializing an ArrayList with a specific capacity?

Sure! You can initialize an ArrayList with a specific capacity like this: ArrayList<String> list = new ArrayList<>(10); This creates an ArrayList that can hold up to 10 elements before needing to resize.

What are the performance implications of using ArrayLists?

ArrayLists provide fast random access but can be slow for insertions and deletions, especially in the middle of the list, due to the need to shift elements.