In Java an identifier can be declared to represent a variable whose possible value is a type!

Such identifiers are called generic parameters.

An identifier must be declared to be a generic identifier.

Below line 2 declares E to be a generic parameter. The scope of E is from line 2 to the end of the class MyList at line 11.

Line 6 is a use of E, not a declaration of E.

If one or more generic parameters is declared in a class header (line 2), the class is said to be a generic class.

    1   
    2   public class MyList<E> // declaration of E
    3   {
    4    
    5     ...
    6     public void add(E x) // Use of E
    7     {
    8   
    9     }
   10   
   11   }