Which collection class allows you to access its elements by associating a key with an element's value, and provides synchronization?

Q: Which collection class allows you to access its elements by associating a key with an element's value, and provides synchronization?

Hashtable is the only class listed that provides synchronized methods. If you need synchronization great; otherwise, use HashMap, it's faster.

java.util.SortedMap
java.util.TreeMap
java.util.TreeSet
java.util.Hashtable

Correct Answer: java.util.Hashtable

Explanation:

Hashtable is the only class listed that provides synchronized methods. If you need synchronization great; otherwise, use HashMap, it's faster.

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