replaceLast.java

public static String replaceLast(String string, String toReplace,
  		String replacement) {
		int pos = string.lastIndexOf(toReplace);
		if (pos > -1) {
			return string.substring(0, pos)
					+ replacement
					+ string.substring(pos + toReplace.length(),
							string.length());
		} else {
			return string;
		}
	}