This week's giveaway is in the EJB and other Java EE Technologies forum. We're giving away four copies of EJB 3 in Action and have Debu Panda, Reza Rahman, Ryan Cuprak, and Michael Remijan on-line! See this thread for details.
No, not everyone knows that a tab is set of fixed number of spaces. Because it isn't. It's just a character. And often displaying it results in displaying a number of spaces instead. But not a fixed number of spaces. A lot of output displays have tab stops at (for example) every 4 positions, so a tab character will be represented by between 1 and 4 spaces. At other times displaying a tab character has no effect at all, as for example in HTML.
But anyway that's all irrelevant if your question is how to replace the pair of characters (backslash, 't') by a single tab character. You do that like this:
That's a hint, so I will leave the other half for you.