I am getting an error and don't know why: Error:(43, 50) java: unreported exception java.lang.Exception; must be caught or declared to be thrown public static String readString() throws Exception { //write your code here InputStream inputStream = System.in; Reader inputStreamReader = new InputStreamReader(inputStream); BufferedReader bufferedReader = new BufferedReader(inputStreamReader); return bufferedReader.readLine(); } ......this seems to have solved the error...but why?? I compared before and after the "fix" and the code is the same...already had Exception ?? The asker of this question here: https://stackoverflow.com/questions/15412555/shortcut-to-add-throws-declaration-in-intellij-idea Said he was accustomed to Eclipse and had just switched to InteliJ When a piece of code needs error handling, IntelliJ underlines it with red. Set your pointer on that piece of code and press ALT+ENTER. IntelliJ should now give you the choice to either surround it with try/catch, add a catch clause, or to add a throws declaration. In your case: click the underlined code → ALT+ENTER → Add Exception to Method Signature