How to easily convert a java8 map to a concurrentMap?

Question

Is there any way to convert java8 Map<K,V> to ConcurrentMap<K,V> other than iterating manually over all entities?

http://stackoverflow.com/questions/510632/whats-the-difference-between-concurrenthashmap-and-collections-synchronizedmap — Hannes, Mar 28 '16 at 10:02

score 3 · Accepted Answer · answered Mar 28 '16 at 10:04

3

There exist the constructor in https://docs.oracle.com/javase/8/docs/api/java/util/concurrent/ConcurrentMap.html

So you can

ConcurrentHashMap(Map m) Creates a new map with the same mappings as the given map.

answered Mar 28 '16 at 10:04

anquegi

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score 0 · Answer 2 · answered Mar 28 '16 at 10:03

0

You could use the ConcurrentHashMap(Map<? extends K,? extends V> m) constructor for example to pass in a Map and construct a ConcurrentHashMap .

JavaDoc

answered Mar 28 '16 at 10:03

Som Bhattacharyya

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score 0 · Answer 3 · answered Mar 28 '16 at 10:09

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If the only thing you need is synchronized view of this map you can use

java.util.Collections#synchronizedMap

Usually, it isn't what you want, because the performance of "synchronized" map is worse in general. But this solution can solve some cases when you want specifically "synchronized view" for your map.

answered Mar 28 '16 at 10:09

SerCe

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what is the difference between "synchronized map" and "synchronized view" – Elad Benda Mar 28 '16 at 10:18
@EladBenda, synchronized view is just synchronized proxy for your map – SerCe Mar 28 '16 at 16:21

How to easily convert a java8 map to a concurrentMap?

3 Answers3