Why use a hash map?

Question

Someone said that hashmaps are pretty slow. So I'm just wondering if to use hashmap or switch logic.

My requirement is this. I have a set of CountryNames and CountryCodes. My ListView displays country names. When the country name element is clicked, I must Toast CountryCode.

In such a scenario, should I support the HashMap of country names and codes and access this in order to get the appropriate code ?:

myMap.put("US", 355);
myMap.put("UK", 459);
//etc

Or is it better to write such a case with a switch

switch (vCountryNamePos):
{
case 0:   //US
vCountryCode = 355;
break;
case 1:   //UK
vCountryCode = 459;
break;

//etc
}

Which is faster? If not Hashmaps, then in what practical scenarios will the map be used?

-Kiki

Answer 1

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