Java Programming

I'm designing a web application that pulls data from several different web services. Each service has its own enums, i.e. to represent a country, a particular service would actually send back a country code as a response to some call. These codes are proprietary per service. For example, in the case of the country Afghanistan:

Service1: ("Afghanistan", 1)
Service2: ("Afghanistan", 239)
Service3: ("Afghanistan", 87)

Additionally, I have my own list of country/ID, which creates a fourth mapping from string to int:

MyApp: ("Afghanistan", 56)

I need to be able to convert from a proprietary country/code mapping to mine for data pulls from the services, and vice versa for data pushes. My question is simply this: Can someone recommend the best strategy for storing and retrieving the information? In a MVC web application (using spring framework), how would you implement the lookups/conversions? I'm stuck on whether to use enum'ed ArrayLists or hash tables.

My application has database access; if I want, I can create a lookup table in the db as well.

Any feedback would be greatly appreciated!!