javahowto

ConcurrentHashMap Examples

4 steps when accessing a cache implemented with java.util.ConcurrentHashMap (javadoc):get the value from the ConcurrentMap;if null, assume it's the first access, and create the value;call putIfAbsent on the concurrentMap to store the new value;if return value is not null (it's rare but happens), use the return value as the golden copy, and discard the newly-created object.The following test class, SqrtTest, displays the square root of...