In Java, how can I change the user input to accept characters for the commands

I need the code to accept the characters $($i$,$ l$,$ u$,$ r$,$ q$)$ for the user input commands, but the console is giving the following error:

Exception in thread "main" java.util.InputMismatchException

at java.base$/$java$.$util.Scanner.throwFor$($Scanner$.$java:$939)$

at java.base$/$java$.$util.Scanner.next$($Scanner$.$java:$1594)$

at java.base$/$java$.$util.Scanner.nextInt$($Scanner$.$java:$2258)$

at java.base$/$java$.$util.Scanner.nextInt$($Scanner$.$java:$2212)$

at com.app.CavazosExample.main$($CavazosExample$.$java:$37)$

The code I have is this:

package com.app;

import java.util.Random;

import java.util.Scanner;

import org.json.simple.JSONArray;

public class CavazosExample $\{$

$$ private static final String fileName $="/$Users$/$envyi$/$Documents$/$GitHub$/$General$\_$Cavazos$\_$App$/$cavazosapp$/$src$/$main$/$java$/$com$/$app$/$commands$.$json";

$$ private static String$[]$ commandArray;

$$ private static int lastIssuedCommandIndex $=-1$;

$$ private static int redoCommandIndex $=-1$;

$$ public static void main$($String$[]$ args$)\{$

$$

$$ JSONArray commandJSONArray $=$ JSONFile.readArray$($fileName$)$;

$$ commandArray $=$ getCommandArray$($commandJSONArray$)$;

$//$ initialize Scanner

$$ Scanner scanner $=$ new Scanner$($System$.$in$)$;

$//$ Menu Commands

$$ boolean running $=$ true;

$$ while $($running$)\{$

$$ System.out.println$("$

General Cavazos Commander App"$)$;

$$ System.out.println$("-----------------------------------------")$;

$$ System.out.println$("$i $$ Issue a command"$)$;

$$ System.out.println$("$l $$ List all of the commands"$)$;

$$ System.out.println$("$u $$ Undo the last command that was issued"$)$;

$$ System.out.println$("$r $$ Redo the last command that was issued"$)$;

$$ System.out.println$("$q $$ Quit"$)$;

$$ System.out.println$("-----------------------------------------")$;

$$ System.out.print$("$Enter a command: $")$;

$$ int choice $=$ scanner.nextInt$()$;

$$ scanner.nextLine$()$;

$$ switch $($choice$)\{$

$$ case $\text{'}$l$\text{'}->$ listCommands$()$;

$$ case $\text{'}$i$\text{'}->$ issueRandomCommand$()$;

$$ case $\text{'}$u$\text{'}->$ undoCommand$()$;

$$ case $\text{'}$r$\text{'}->$ redoCommand$()$;

$$ case $\text{'}$q$\text{'}->\{$

$$ System.out.println$("$Quitting the app..."$)$;

$$ running $=$ false;

$\}$

$$ default $->$ System.out.println$("$Invalid option. Please try again."$)$;

$\}$

$\}$

$$ scanner.close$()$;

$\}$

$//$ print list of all commands

private static void listCommands$()\{$

$$ System.out.println$("-----$ List of all commands $-----")$;

$$ print$($commandArray$)$;

$\}$

private static void issueRandomCommand$()\{$

$$ Random rand $=$ new Random$()$;

$$ lastIssuedCommandIndex $=$ rand.nextInt$($commandArray$.$length$)$;

$$ System.out.printf$("$

$---$ Issuing Random Cammands $---$

$\%$s

$",$ commandArray$[$lastIssuedCommandIndex$])$;

$$ redoCommandIndex $=-1$;

$\}$

$//$ Undo last command

private static void undoCommand$()\{$

$$ if $($lastIssuedCommandIndex $==-1)\{$

$$ System.out.println$("$No command to undo."$)$;

$\}$

$$ else $\{$

$$ System.out.printf$("$

$---$ Undo Command $---$

$\%$s

$",$ commandArray$[$lastIssuedCommandIndex$])$;

$$ redoCommandIndex $=$ lastIssuedCommandIndex;

$$ lastIssuedCommandIndex $=-1$;

$\}$

$\}$

$//$ Redo last command

$$ private static void redoCommand$()\{$

$$ if $($redoCommandIndex $==-1)\{$

$$ System.out.println$("$No command to redo."$)$;

$\}$

$$ else $\{$

$$ System.out.printf$("$

$---$ Redo Command $---$

$\%$s

$",$ commandArray$[$redoCommandIndex$])$;

$$ lastIssuedCommandIndex $=$ redoCommandIndex;

$$ redoCommandIndex $=-1$; $//$ Reset redo index

$\}$

$\}$

$//$ print command array

$$ public static void print$($String$[]$ commandArray$)\{$

$$ System.out.printf$("$Number$\backslash$tCommand

$")$;

$$ System.out.printf$("------\backslash$t$---------------$

$")$;

$$ for $($int i $=0$; i $<$ commandArray.length; i$++)\{$

$$ System.out.printf$("\%04$d$\backslash$t$\%$s

$",$ i$,$ commandArray$[$i$])$;

$\}$

$\}$

$//$ get names from json object

$$ public static String$[]$ getCommandArray$($JSONArray commandArray$)\{$

$$ String$[]$ arr $=$ new String$[$commandArray$.$size$()]$;

$$ for $($int i $=0$; i $<$ commandArray.size$()$; i$++)\{$

$$ arr$[$i$]=$ commandArray.get$($i$).$toString$()$;

$\}$

$$ return arr;

$\}$

$\}$