json - Java-8 JSONArray to HashMap -

i'm trying convert jsonarray map<string,string> via streams , lambdas. following isn't working:

org.json.simple.jsonarray jsonarray = new org.json.simple.jsonarray(); jsonarray.add("pankaj"); hashmap<string, string> stringmap = jsonarray.stream().collect(hashmap<string, string>::new, (map,membermsisdn) -> map.put((string)membermsisdn,"error"), hashmap<string, string>::putall); hashmap<string, string> stringmap1 = jsonarray.stream().collect(collectors.tomap(member -> member, member -> "error")); 

to avoid typecasting in line 4, i'm doing line 3

line 3 gives following errors:

multiple markers @ line - type hashmap<string,string> not define putall(object, object) applicable here - method put(string, string) undefined type object - method collect(supplier, biconsumer, biconsumer) in type stream not applicable arguments (hashmap<string, string>::new, (<no type> map, <no type> membermsisdn)   -> {}, hashmap<string, string>::putall) 

and line 4 gives following error:

type mismatch: cannot convert object hashmap<string,string> 

i'm trying learn lambdas , streams. can me out?

it appear json-simple's jsonarray extends arraylist without providing generic types. causes stream return stream doesn't have type either.

knowing this, can program on interface of list instead of jsonarray

list<object> jsonarray = new jsonarray(); 

doing allow stream so:

map<string, string> map = jsonarray.stream().map(object::tostring).collect(collectors.tomap(s -> s, s -> "value"));