What is the closest to ConcurrentHashMap and NavigableMap in Java?

[Jacek Furmankiewicz]

On Thursday, 14 November 2013 at 21:39:53 UTC, bearophile wrote:
> Jacek Furmankiewicz:
>
>> hashmap per thread is not an option. The cache may be a few 
>> GBs of data, there is no way we can duplicate that data per 
>> thread.
>
> But is the D garbage collector able to manage efficiently 
> enough associative arrays of few gigabytes? You are not dealing 
> with a GC nearly as efficient as the JavaVM one.
>

Well, these are the types of questions I have as a Java veteran
who is having a first look at D after the recent Facebook 
announcement.

By now I have a decent idea of where most of the new languages 
(Go has same issues, for the most part) come up short when 
compared to Java's very mature SDK, so that is usually where I 
start probing first.

Sorry :-(