count cache key number

[wkhapy...@gmail.com]

Hi,
    I have a cache ,it's key like 
   "mobile:140000"
   "mobile:140001",
    "address:test1",
    "address:test2",
    "address:test3"。
   I want to count mobile number and address number。
   address number is 3 and mobile number is 2。I see Ignite doc has mapreduce 
job，but it seem not example iterator cache key。 is there any method to iterator 
key in mapreduce job。Thank you very much



wkhapy...@gmail.com