ArrayLists are generally preferred over LinkedLists in many use-cases due to several performance advantages:
Constant-Time Random Access: ArrayLists provide constant-time complexity ($$O(1)$$) for random access of elements. This is because ArrayLists use a dynamic array as their underlying data structure, allowing direct access to any element using its index. This makes ArrayLists highly efficient for scenarios where frequent read operations are required[1][2][4][5][6][9][11][18][19].
Better Memory Utilization: ArrayLists store elements in contiguous memory locations, which can be more cache-friendly. This means that when an element is accessed, the surrounding elements are likely to be pre-loaded into the cache, leading to faster access times. LinkedLists, on the other hand, store nodes non-contiguously, and each node contains additional overhead for storing references to the next (and previous, in the case of doubly-linked lists) nodes, which can lead to higher memory usage and less efficient cache utilization[1][2][4][6][8][11][18].
Less Memory Overhead: Each element in an ArrayList is just the data itself, whereas each element in a LinkedList is a node that contains the data and two references (for doubly-linked lists) to the next and previous nodes. This additional overhead can make LinkedLists less memory-efficient, especially when the list nodes are small[1][2][4][6][8][11][18].
Efficient Resizing: While it's true that ArrayLists need to resize when they run out of capacity, this operation is typically amortized to be a constant-time operation. The resizing operation involves creating a new array and copying the elements, which is a relatively fast operation due to the use of System.arraycopy() in Java. LinkedLists do not require resizing, but the cost of additional memory overhead per element often outweighs the resizing cost of ArrayLists[1][2][4][5][6][11][18][19].
Insertions and Deletions: Although LinkedLists can theoretically offer constant-time complexity for insertions and deletions at any point in the list, in practice, these operations often require traversal from the head of the list to the point of insertion or deletion, which can be costly ($$O(n)$$). For ArrayLists, insertions and deletions are costly only when they occur in the middle of the list, as they require shifting elements. However, for operations at the end of the list, ArrayLists perform w...
