As others have mentioned, using
switch(input) {
case "a":
// do stuff
break;
case "b":
// do more stuff
break;
}
will work. Just another thing, if you are working in java 7 (java -version), you should be able to get rid of
BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
and replace it with
Scanner in = new Scanner(System.in);
String input = in.nextLine();
Which at least to me is a lot easier to use. Just import
import java.util.Scanner;