Langauge java, having trouble handling this exception below

Exception in thread "main" java.lang.NumberFormatException: For input string: ""

at java.base/java.lang.NumberFormatException.forInputString(NumberFormatException.java:65)

at java.base/java.lang.Integer.parseInt(Integer.java:662)

at java.base/java.lang.Integer.parseInt(Integer.java:770)

at a5.Assign5Main.main(Assign5Main.java:24)

Code: public static void main(String[] args) throws IOException { JOptionPane.showMessageDialog(null, welcomeMessage); Thesaurus mythesaurus = new Thesaurus();

int userSelection = 0; while (userSelection != QUIT) {  //line24  userSelection = Integer.parseInt(JOptionPane.showInputDialog(promptMessage)); processSelection(mythesaurus, userSelection); } }