Ok, so I was reading the Java online tutorial for generics and I found this:
E - Element (used extensively by the Java Collections Framework)
K - Key
N - Number
T - Type
V - Value
S,U,V etc. - 2nd, 3rd, 4th types
I have seen a lot of methods in Java use the "E" notation but I was looking for a method that uses the "K", key notation. Anyone can help please?
Theres no real need to use K, V, E, T etc in your own classes but they are nice standards.
ReplyDeleteK and V for example are used by Map. A good example of K and V is a HashMap!
HashMap<K, V> hm = new HashMap<K, V>();
And implementing:
HashMap<Integer, String> hm = new HashMap<Integer, String>();
The HashMap (java.util.HashMap<K,V>) uses it for example.
ReplyDeletePretty sure a Map K uses and V
ReplyDeletepublic interface Map<K,V>
java.util.Map is defined:
ReplyDeletepublic interface Map<K, V> { ... }