HashTable Benefits

Question

What is the main advantage of using Hashtablecompared to HashMap. Because the Hashtablemain advantage is synchronization. Now the card can also sync with synchronizedMap().

Map m = Collections.synchronizedMap(hashMap);

Answer 1

Hashtableexisted before collections, so it is saved mainly for backward compatibility. Use instead ConcurrentHashMap.

Please note that there is a small semantic difference - it Hashtabledoes not allow null values, but HashMapallows null values ​​and a null key.

Answer 2

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