How does the performance of ArrayList in Java compare to other data structures?

How does the performance of ArrayList in Java compare to other data structures?

ArrayList in Java offers fast random access and is generally efficient for adding elements at the end. However, it can be slower for insertions and deletions in the middle due to shifting elements.

What are the time complexities for common operations in ArrayList?

The time complexities for ArrayList operations are:

• Access: O(1)
• Add (end): O(1)
• Add (middle): O(n)
• Remove: O(n)
• Search: O(n) for unsorted lists.

When should I use ArrayList over LinkedList?

Use ArrayList when you need fast access and are primarily adding/removing elements at the end. Choose LinkedList for frequent insertions and deletions in the middle.

Are there any performance issues with ArrayList?

Yes, ArrayList can face performance issues with resizing when it exceeds its capacity, leading to O(n) time complexity for resizing operations.

What alternatives to ArrayList should I consider?

Consider using LinkedList for frequent insertions/deletions, or HashSet for unique elements with fast access.