The kcontext is a special variable of the type RuleContext. If you take a look at that interface and all the inheritance you will find out which methods you can use.
You can do something like:
kcontext.getKnowledgeRuntime().getObjects() and then look for the HashMap.
I'm not sure what do you want to achieve.. but as you may notice this is not a clean solution.. you probably can change the shape of your solution to something better, if you share with us what are you trying to achieve, maybe we can help.
Cheers