Different Ways of Creating HashMaps

Question

I\'ve been learning about HashMaps recently but I have one question that I can\'t seem to get a clear answer on. The main difference between -

HashMap hash1          


        

Answer 1

Specifying the key and the value types allows for greater type-safety by enabling compile-time typing enforcement.

This makes it easier to write code that doesn't accidentally mix up the key and value types, and reduces the amount of casts that you must explicitly declare in the code.

However, it is important to be aware the these type-checks are compile-time only, i.e. once the application is running, the JVM will allow you to use any types for the keys and values.