About Question com.enthuware.ets.scwcd.v5.2.558 :

[rlrao1987]

Since the question asks for storing headers accompanying a request(and not specifically for their names), option 2 should also be correct.

[admin]

The requirement in the question is "with least impact to existing code". Changing all the jsps will impact a lot of existing code. A filter has no impact on the existing code.