Verification component reuse is one of the basic requirement when building verification components.Parameterized class play a very important role in making a code generic. With parameterized class in system verilog data types , size of bit vectors can be declared generic in the class , different variations of the class can be created by varying the parameter value.
Example of a parameterized class
class data # ( type t=int , int size=8 )
t a ;
bit [ size-1 : 0] b ;
endclass
data # ( shortint , 16 ) halfword_data;
data # ( longint , 32) word_data;