In Java, finding a class that maintains key-value associations and preserves insertion order can be challenging. The Hashtable class, commonly used for this purpose, presents difficulties in retrieving values in their original order.
For this scenario, consider leveraging LinkedHashMap or TreeMap. LinkedHashMap preserves the order in which keys are inserted, making it suitable for displaying values in a specific sequence. TreeMap, on the other hand, sorts keys based on a Comparator or natural ordering, allowing for retrieval of values based on their order.
LinkedHashMap offers faster performance in most cases due to its O(1) complexity for operations like containsKey, get, put, and remove. TreeMap, with its O(log n) complexity, is ideal when a specific sort order is required.
If your API only expects predictable sort order, consider using NavigableMap or SortedMap interfaces. These interfaces allow you to abstract your implementation and easily swap between LinkedHashMap or TreeMap or even different implementations in the future.
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