Something

String output = "I\\AM\\So\\Cool";

while (true) {
	int pos = output.indexOf("\\");
	if (pos == -1) 
		break;

	int spacePos = output.indexOf(" ");

	String tok = output.substring(0, pos);
	String end = output.substring(pos+1);

	if (spacePos == -1)
		output = end + " " + tok;
	else
		output = end.substring(0, spacePos) + tok + end.substring(spacePos);
}