public static boolean isHex(String input) {
		input = input.replaceAll("\\s", "");
		return input.matches("[0-9a-fA-F]+");
	}
Returns true if the input is a valid hex string.  

Note that spaces are allowed in the input, but are ignored.

@param input
@return
Ghidra/Features/Base/src/main/java/ghidra/app/plugin/core/instructionsearch/util/InstructionSearchUtils.java