there's a very easy way to get the spawner an its as the same way of how to get the command block.
well, you need to do the following things:

1.- in a cheat enabled game press the chat ( if u dont know how put the controlls in the menu and there you will see)
2.- put the following command: /give <Player> 52
3.- it's done now you have an infinity of pigs! ( to murder)

any questions please in the commentaries
if you want more cool stuff subscribe.

Bye Bye