groupingByConcurrent javadoc shows an example use that does not require a map factory
brian.goetz at oracle.com
Mon Jun 17 16:21:59 PDT 2013
No, the default factory is HashMap::new. This asks for a TreeMap, which
has the additional property of having a sorted encounter order for keys.
On 6/17/2013 7:13 PM, Arul Dhesiaseelan wrote:
> Looks like this example in Collectors javadoc needs to be corrected for
> groupingByConcurrent that does not take a map factory?
> ConcurrentMap<City, Set<String>> namesByCity
> people.stream().collect(groupingByConcurrent(Person::getCity, TreeMap::new,
> mapping(Person::getLastName, toSet())));
> map factory should not be included in this example, as it uses the default
> - Arul
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