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Trying to create a quiz with java, but something went wrong. What part of my program did i screw up?

So I'm starting to get the hang of java, and I'm creating a quiz as a mini project. However, when I get to the input part of my program, it breaks down. What's going on?
I also apologize for the formatting
import java.util.Scanner;
public class Test {
public static void main(String[] args)
{
Scanner in = new Scanner(System.in);
int score = 0;
int total = 0;
System.out.println("Are you ready for a quiz? (Y/N)");
char answer = in.findInLine(".").charAt(0);
if (answer == 'Y' || answer == 'y');
{
String a = "Barrow";
String b = "Juneau";
String c = "Anchorage";
String d = "Annapolis";
System.out.println("Alright! Lets get right to it!");
System.out.println("What is the Capital of Alaska?");
System.out.println("A: " + a);
System.out.println("B: " + b);
System.out.println("C: " + c);
System.out.println("D: " + d);
char choice = in.findInLine(".").charAt(0);
if (choice == 'B' || choice == 'b')
{
System.out.println("Good Job! 1 point for you!");
score = score + 1;
}
else
{
System.out.println("Incorrect! the answer was actually " + b);
}
String e = "Yes";
String f = "No";
System.out.println("Alright, Next Question! Can you"
+ " store the value 'cat' in a variable of type int?");
System.out.println("A: " + e);
System.out.println("B: " + f);
char secchoice = in.findInLine(".").charAt(0);
if (secchoice == 'A' || secchoice == 'a')
{
System.out.println("Correct! Good Job!");
score = score + 1;
}
else
{
System.out.println("Incorrect");
}
System.out.println("What is the result of 2+2X3-5?");
int result = in.nextInt();
if (result == 3)
{
System.out.println("Correct! Good Job!");
}
else
{
System.out.println("Incorrect");
}
System.out.println("Your total score was " + score + "out of 3");
}
}
}

You are getting a NullPointerException on line 26 because of the way that findInLine() works. Basically, you have used up the one line of input you give it when it starts and the Scanner has advanced passed it to find the next one (which does not exist). In other words, you should use another method for Scanner or use an entirely different approach for getting input.
For example, it is preferable to use this technique
char answer = in.nextLine().charAt(0);
because nextLine() will wait until it has more input.
Of course, you will have to come up with some way to parse the input from the user to make sure that it is valid (i.e. if they can only choose between 'Y' and 'N' you handle the case where they choose neither).
That would look something like
char answer = parseInput(in.nextLine().charAt(0));
where parseInput(String s) is a method you write yourself.
As far as other approaches go, this tutorial from Oracle can help you get started.

Hangman stats error

My code does not show the number of wins, losses and numberOfGames I had played.
I've been trying to fix it for the last month and I'm going nowhere!
import java.util.Random;
import java.util.Scanner;
public class HangmanP2 {
public static void main(String[] args) {
Scanner Input = new Scanner(System.in);
String first, reverse = "";
String second, reverse2 = "";
Scanner in = new Scanner(System.in);
System.out.println("Welcome to Hangman!");
System.out.println("Enter your first name.");
first = in.nextLine();
System.out.println("Enter your last name to play.");
second = in.nextLine();
int length = first.length();
int length2 = second.length();
for ( int i = length - 1 ; i >= 0 ; i-- )
reverse = reverse + first.charAt(i);
reverse = reverse.substring(0,1).toUpperCase() + reverse.substring(1).toLowerCase();
for ( int i = length2 - 1 ; i >= 0 ; i-- )
reverse2 = reverse2 + second.charAt(i);
reverse2 = reverse2.substring(0,1).toUpperCase() + reverse2.substring(1).toLowerCase();
System.out.println("Your name entered in reverse is: "+reverse+" "+reverse2);
startGame(reverse,reverse2);
}
public static void startGame(String reverse,String reverse2){
Random rnd = new Random ();
Scanner user = new Scanner (System.in);
String guess = "";
String message = "";
int count = 1;
boolean quit = false;
String fullWord = "";
int wins=0;
int loss=0;
int numberOfGames=0;
int guessC = 5;
String usedLetters ="";
String remainingLetters ="";
String letters = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
int hinter = 0;
int z = rnd.nextInt(10);
int k = rnd.nextInt(2);
String words[][] = {{"earth","stars","light",
"world","about","again",
"stars","light","music",
"happy","water","amber",
"apple","piano","green",
"mouth","suger","stone",
"japan","china","after","lemon",
"grand",
"lives","twice","print"},{"smile",
"puppy","latin","vegan","phone","april",
"south","house","hangs","woman",
"power","today","india","night","candy",
"forum","birth","other","chris","irish",
"paste","queen","grace","crazy","plant",
"knife","spike","darth","vader","eagle",
"egypt","range","fists","fight","glory",
"March","smart","magic","codes","rolls",
"match","honor","glass","board","teams",
"bully","zebra","under","mango","brain",
"dirty","eight","zeros","train","cycle",
"break","necks","terms","slide","large"},{"stake","guess","wrong","anime","stick","outer","input"},{ "thing","write","white","black"}};
//Prints info of the game and topic that as been selected
System.out.println("Welcome to Hangman"+" "+reverse+" "+reverse2);
//This prints the '-' and spaces for the first run of the game only
for(int index = 0; index < words[z][k].length();index++)
{
Character variableInt = words[z][k].charAt(index);
if(variableInt != ' ')
{
message += "-";
}
else
{
message += " ";
}
}
//Nothing will change, this prints information to the user about his current status in-game.
System.out.println("Secret word: \t\t" + message);
System.out.println("Letters Remaining: " + letters);
System.out.println("Letters Used: ");
System.out.println("Guesses Remaining: " + guessC);
//The loop that will continuously run the game, until the user fails or does not want to play again.
do{
//The following variable's make sure there is not stacking from previous data when the loop runs again.
remainingLetters = "";
count = 0;
//Ask the user for a letter to guess
System.out.println("\nEnter a letter to guess the word): ");
guess = user.nextLine();
//The following for-loop converts ASCII table [A-Z] to actually characters and if the player used a letter it will not show up or add to the string each run of the do-loop.
for(int x = 65; x < 91;x++){
Character current = new Character ((char)x);
String current2 = current.toString();
if(!usedLetters.contains(current2)){
remainingLetters += current;
}
}
//Converts the user's first character to a string which is converted into another character and again converted into a String (Seem's useless) but i used it this way cause i was getting an error.
Character convert = new Character (guess.charAt(0));
Character conv = new Character (convert);
String converted = convert.toString();
//The letters the player uses will be added to a string, if it has not already been added and only if it is a letter.
if(!usedLetters.contains(converted) && conv.isLetter(convert)){
usedLetters+=guess.charAt(0);
}
//Inside this for-loop it turns our word into a String and the user's first character into a string.
for(int index = 0; index < words[z][k].length();index++){
//This is a helper
count++;
//Conversion of variables
Character current2 = new Character ( words[z][k].charAt(index));
String current = current2.toString();
Character current3 = new Character (guess.charAt(0));
String current4 = current3.toString();
String current5 = current4.toUpperCase();
String current6 = words[z][k].toUpperCase();
//If the players gets a letter correct, do the following.
if(current4.equalsIgnoreCase(current))
{
//Add's on to the previous string from where the player got it correct and change it to the correct letter instead of a '-'.
message = message.substring(0,index) + guess + message.substring(index + 1);
}
//If the player gets it wrong and the helper variable is equal to 1 (so that it does not follow the loop of the for-loop and it is not one of the special characters in the game('!' or '?').
if(!current6.contains(current5) && count == 1 && guess.charAt(0) != '?' && guess.charAt(0) != '!'){
guessC--;
}
}
//Prints information to the user of their current topic
//The secret word the player has to guess
System.out.println("Secret word: \t\t" + message.toUpperCase());
//The letters in the alphabet that have not been used yet
System.out.print("\nLetters remaining: ");
System.out.print(remainingLetters.toUpperCase() + "\n\n");
//This will print a message to the user, telling them information on using a hint or the hint itself.
//Letters the user has used since the game session has been running
System.out.print("\nLetters Used: ");
System.out.print(usedLetters.toUpperCase() + "\n");
//The amount of guesses the player has left
System.out.println("\nGuesses Remaining: " +guessC );
//If the player enters a '?' it will do the following.
if(guess.charAt(0) == '?'){
if(hinter <2){
//Displays what is in the array and information about the delay, while losing guesses.
hinter++;
System.out.print("\nHint will appear after next guess! \n");
guessC -=2;
}
}
//If the user guesses the word correct
if(message.equalsIgnoreCase(words[z][k])){
System.out.println("YOU ARE CORRECT! " + words[z][k] + " is correct!");
wins++;
quit = true;
}
//If the user ask to guess the entire word it is stored in a separate variable and make quit equal to true.
if(guess.charAt(0) == '!')
{
System.out.print("\nEnter the secret word: ");
fullWord = user.nextLine();
//if the user guesses the word correct then it will tell the user they are correct and make quit equal to true.
if(fullWord.equalsIgnoreCase(words[z][k])){
System.out.println("YOU ARE CORRECT! " + words[z][k] + " is correct!");
wins++;
quit = true;
}
//If the user does not get it right it will tell the user they are wrong and make quit equal to true.
else{
System.out.println("YOU ARE INCORRECT! the word is: " + words[z][k] + " ");
loss++;
quit = true;
}
}
//If the guesses counter equal 0 then it will tell them that they have lost and make quit equal to true.
if(guessC == 0){
System.out.println("GAME OVER! The secret word was [ " + words[z][k] + " ]!");
loss++;
quit = true;
}
//This is what happens when quit eventually becomes true, the user is asked if they would like to play again.
if(quit == true){
System.out.println("\nWould you like to play again (Y or quit)? ");
System.out.println("\nOr type [stats] to check your work");
guess = user.nextLine();
//If they do want to play again, they will need to enter Y and if they do it will give them another word to guess and resets there information so that there will be no overlap.
if(guess.equalsIgnoreCase("Y")){
quit = false;
z = rnd.nextInt(10);
k = rnd.nextInt(2);
guess = " ";
guessC = 6;
message = "";
usedLetters = "";
hinter = 0;
for(int index = 0; index < words[z][k].length();index++)
{
Character variableInt = words[z][k].charAt(index);
if(variableInt != ' ')
{
message += "-";
}
else
{
message += " ";
}
}
System.out.println("Secret word: \t\t" + message);
System.out.println("Letters Remaining: " + letters);
System.out.println("Letters Used: ");
System.out.println("Guesses Remaining: " + guessC);
}
if(guess.equals("stats")){
printGameStats(wins,loss,numberOfGames);
}
else{
//If the user enters 'N' then they will be told the following and the scanner will be closed.
System.out.println("THANK YOU FOR PLAYING HAVE A GOOD DAY!");
user.close();
}
}
//end of the while loop which will only stop if quit equals true.
}while(quit != true );
}
private static void printGameStats(int wins,int loss,int numberOfGames) {
// Line
System.out.print("+");
printDashes(37);
System.out.println("+");
// Print titles
System.out.printf("| %6s | %6s | %12s |\n",
"WINS", "LOSSES", "GAMES PLAYED");
// Line
System.out.print("|");
printDashes(10);
System.out.print("+");
printDashes(10);
System.out.print("+");
printDashes(10);
System.out.print("+");
printDashes(16);
System.out.print("+");
printDashes(18);
System.out.println("|");
// Print values
System.out.printf("| %6d | %6d | %12d |\n",
wins, loss, numberOfGames);
// Line
System.out.print("+");
printDashes(37);
System.out.println("+");
}
private static void printDashes(int numberOfDashes) {
for (int i = 0; i < numberOfDashes; i++) {
System.out.print("-");
}
}
}

A "Stick Game" program in Java not working correctly?

I've recently decided that I want to make a program that plays a game called "Nim," which is a game in which you start with a predetermined amount of "sticks" and each player takes turns removing between 1 and 3 sticks. Whoever removes the last stick loses.
Anyway, I have written my program and it compiles and runs almost flawlessly. There's only one small problem. After the game is over, it shows the "good game" screen twice, with the game's very first line appearing in the middle (I'll post screenshots at the end here). It's very strange, and I was just wondering if you guys could give it a look.
I'm cutting a chunk of the program out (only one class, named Cup()), because it's somewhat long, so if you see a class you don't recognize then just ignore it. It's pretty self explanatory what the class does in the program, and it's not where the error is occurring. Here's the code.
class SticksGame
{
public static void main(String[] args) throws InputMismatchException
{
Random r = new Random();
int score1 = 0, score2 = 0;
Cup c = new Cup();
int j = 0, d = 0, i = 0, k = 0;
boolean b = true;
String exit = "default";
Scanner input = new Scanner(System.in);
System.out.println("Welcome to the Sticks Game! Last Stick loses! Must pick 1 - 3 sticks.");
System.out.println();
do
{
i = r.nextInt(15) + 9;
System.out.println("We begin with " + i + " sticks");
System.out.println();
while (b == true)
{
System.out.println("Your move");
k = input.nextInt();
if (k > 3)
{
System.out.println("You must select between 1 and 3 sticks");
k = input.nextInt();
}
else if (k < 1)
{
System.out.println("You must select between 1 and 3 sticks");
k = input.nextInt();
}
else
{
j = i;
i = i - k;
if (i <= 0)
{
System.out.println("Computer wins!");
score2 = (score2 + 1);
b = false;
}
else
{
System.out.println("We now have " + i + " sticks.");
}
d = c.select();
System.out.println("Computer removes " + d + " sticks");
i = i - d;
System.out.println("We now have " + i + " sticks");
if (i <= 0)
{
System.out.println("You Win!");
score1 = (score1 + 1);
b = false;
}
}
}
System.out.println();
System.out.println("Good game!");
System.out.println("Your score: " + score1 + " Computer's Score: " + score2);
System.out.println("Press enter if you'd like to play again. Otherwise, type \"quit\"");
exit = input.nextLine();
b = true;
}
while(!"quit".equals(exit));
}
}
Any helps are appreciated! Thanks :)
~Andrew
CODE EDITED FOR JANOS
A little late, I know, but here is the FULL GAME for anyone who wants to play! feel free to copy and paste it into your notepad and execute using cmd(YOU MUST KEEP MY NAME AS A COMMENT ON TOP!) :)
//Andrew Mancinelli: 2015
import java.util.*;
import java.io.*;
class Cup
{
private ArrayList<Integer> c = new ArrayList<Integer>();
public Cup()
{
c.add(1);
c.add(2);
c.add(3);
}
public int count()
{
return c.size();
}
public int select()
{
int index = (int)(c.size() * Math.random());
return c.get(index);
}
public void remove(Integer move)
{
c.remove(move);
}
}
class SticksGame
{
public static void help()
{
System.out.println();
System.out.println("Okay, so here's how it works... The object of the game is to NOT have the last stick. Whoever ends up with the very last stick loses.");
System.out.println();
System.out.println("Rule 1: You will each take turns removing sticks. you may only remove 1, 2, or 3 sticks in a turn");
System.out.println();
System.out.println("Rule 2: The beginning number of sticks is always random between 9 and 24 sticks");
System.out.println();
System.out.println("Rule 3: Whoever chooses the last stick, LOSES!");
System.out.println();
System.out.println("And that's it! Simple, right?");
}
public static void main(String[] args) throws InputMismatchException
{
Random r = new Random();
int score1 = 0, score2 = 0;
Cup c = new Cup();
int j = 0, d = 0, i = 0, k = 0;
boolean b = true;
String exit = "default", inst = "default";
Scanner input = new Scanner(System.in);
System.out.println("Welcome to the Sticks Game! Last Stick loses!");
System.out.println();
System.out.println("Need some instructions? Type \"help\" now to see the instructions. Otherwise, press enter to play!");
inst = input.nextLine();
if (inst.equals("help"))
{
help();
System.out.println();
System.out.println("press \"enter\" to begin!");
inst = input.nextLine();
}
do
{
i = r.nextInt(15) + 9;
System.out.println();
System.out.println("We begin with " + i + " sticks");
System.out.println();
while (b == true)
{
System.out.println("Your move");
k = input.nextInt();
if (k > 3)
{
System.out.println("You must select between 1 and 3 sticks");
k = input.nextInt();
}
else if (k < 1)
{
System.out.println("You must select between 1 and 3 sticks");
k = input.nextInt();
}
else
{
j = i;
i = i - k;
if (i <= 0)
{
System.out.println("Computer wins!");
score2 = (score2 + 1);
b = false;
break;
}
else
{
System.out.println("We now have " + i + " sticks.");
}
d = c.select();
i = i - d;
if (i >= 0)
{
System.out.println("Computer removes " + d + " sticks");
System.out.println("We now have " + i + " sticks");
}
if (i <= 0)
{
System.out.println("You Win!");
score1 = (score1 + 1);
b = false;
break;
}
}
}
System.out.println();
System.out.println("Good game!");
System.out.println("Your score: " + score1 + " Computer's Score: " + score2);
System.out.println("Press enter if you'd like to play again. Otherwise, type \"quit\"");
input.nextLine();
exit = input.nextLine();
b = true;
}
while(!"quit".equals(exit));
}
}

The problem is that this condition is always true:
while (exit != "quit");
Because != means "not identical",
and the exit variable and "quit" are not identical.
Use the equals method for checking logical equality.
In this example, change the loop condition to this instead:
while (!"quit".equals(exit));
For your other problem of not properly starting a second game,
you need to reinitialize the state variables,
for example reset b = true.
Lastly, note that input.nextInt() doesn't read the newline character that you pressed when entering a number. So when exit = input.nextLine() runs, it reads that newline character, and doesn't actually give you a chance to type "quit". To solve this, add input.nextLine(); right before exit = input.nextLine();

The unexpected retry was because of the use of input.nextLine(); the program assumed that you already pressed [enter].
From previous work, the two options is to insert one more input.nextline();
input.nextLine();
exit = input.nextLine();
Or use input.next(); instead, although enter will not work for this method so you may need to enter any key or "quit" to exit;
exit = input.next();

Cannot accurately asses Strings

I wrote some code that is supposed to ask for input from the user and assign it to the String skillAssign. When I try to asses skillAssign, it returns false no matter what. Here is my code:
import java.util.*;
public class CharacterCustomization
{
public CharacterCustomization()
{
}
public static void Customization()
{
Scanner keyboard = new Scanner(System.in);
int skillPoints = 100;
String skillAssign = "";
int newMaxHealth = 0;
int newMaxMagic = 0;
int newMaxStamina = 0;
int assignmentValue = 0;
boolean isDone = false;
System.out.println("Welcome to character customization, you have 100 points to allocate to your skills.");
System.out.println("To allocate points, type name of skill, followed by the points you want to assign (blank for positive, - for negative, ex. -5)");
System.out.println("Put Skill on one line, and press enter, then the value on the next line");
System.out.println("Type \"stats\" to view full stats at any time");
System.out.println("Type \"done\" to finish");
while (true)
{
while (isDone == false)
{
skillAssign = keyboard.nextLine();
if (skillPoints == 0)
{
System.out.println("Max Health: " + newMaxHealth);
System.out.println("Max Magic: " + newMaxMagic);
System.out.println("Max Stamina: " + newMaxStamina);
System.out.println("Skill points left: " + skillPoints);
System.out.println("Type \"done\"to finish");
}
if ((!(skillAssign.equals("stats"))) || (!(skillAssign.equals("done"))))
{
assignmentValue = keyboard.nextInt();
if (((skillAssign.equals("health")) || (skillAssign.equals("Health"))) && (skillPoints - assignmentValue >=0))
{
skillPoints = (skillPoints - assignmentValue);
newMaxHealth = (assignmentValue + newMaxHealth);
}
else if (((skillAssign.equals("magic")) || (skillAssign.equals("Magic"))) && (skillPoints - assignmentValue >=0))
{
skillPoints = (skillPoints - assignmentValue);
newMaxMagic = (assignmentValue + newMaxMagic);
}
else if (((skillAssign.equals("stamina")) || (skillAssign.equals("Stamina"))) && (skillPoints - assignmentValue >=0))
{
skillPoints = (skillPoints - assignmentValue);
newMaxStamina = (assignmentValue + newMaxStamina);
}
else
{
//System.out.println("Sorry, I could not read that!");
System.out.println(skillAssign == "stats");
}
}
else if (skillAssign.equals("stats"))
{
System.out.println("Max Health: " + newMaxHealth);
System.out.println("Max Magic: " + newMaxMagic);
System.out.println("Max Stamina: " + newMaxStamina);
System.out.println("Skill points left: " + skillPoints);
}
else if ((skillAssign.equals("done")) || (skillAssign.equals("Done")))
{
isDone = true;
continue;
}
else
{
System.out.println("Sorry, I could not read that!");
}
}
System.out.println("Are you sure this is the setup you want? [y] [n]");
System.out.println("Max Health: " + newMaxHealth);
System.out.println("Max Magic: " + newMaxMagic);
System.out.println("Max Stamina: " + newMaxStamina);
System.out.println("Skill points left: " + skillPoints);
//skillAssign = keyboard.nextLine();
if (((keyboard.nextLine()).equals("y")) || ((keyboard.nextLine()).equals("Y")) || ((keyboard.nextLine()).equals("yes")) || ((keyboard.nextLine()).equals("Yes")))
{
Player player = new Player(newMaxHealth, newMaxMagic, newMaxStamina);
}
else
{
isDone = false;
}
}
}
}
Its not complete, but Im inputting stats when prompted and all evaluations of it are false
Is there a way I can get it to read the variable properly?

You will always get in inside this condition scope if ((!(skillAssign.equals("stats"))) || (!(skillAssign.equals("done"))))
It because that when one word failed to pass it, the other condition will let it pass, because they are different completely.
e.g:
let's take "stats", this will results with if (false || true) => true.
let's take "done", this will results with if (true || false) => true.
let's take "sTats", this will results with if (true || true) => true.
You can't escape it, you need to check it like that:
if (!(skillAssign.equals("stats") || skillAssign.equals("done")))
this way we're checking if either of the logical expression are true, then we change it to "not" and then checking if the whole condition is true.
P.S
A. You can use "abc".equalsIgnoreCase("AbC") instead what you're using now.
B. Don't add for every logical expression parenthesis it's making the code more complex and unclear for the first glance.

The problem was that I was using || instead of && in the if ((!(skillAssign.equals("stats"))) || (!(skillAssign.equals("done"))))

What ever Orel said is pretty much it. Just wanna add if you are using System.out.println(skillAssign == "stats") to asses your skillAssign it will always return false, even if they have the same value.
Because == compare the reference of Strings not their values.
you must use equals() method.

try-catch doesn't catch IOException

In the following code, I get the Unreachable catch block for IOException. This exception is never thrown from the try statement body error(underlined) with the IOException in } catch (IOException e){ what am I doing wrong?
class driver {
public static void main(String[] args) {
// TODO Auto-generated method stub
Customer forrest = new Customer("Forrest Gump", 1,
"42 New Street, New York, New York");
Customer random = new Customer("Random Name", 2,
"44 New Street, New York, New York");
Customer customer[] = { null, forrest, random };
int whichOption = 1;
int id = 0;
char action = ' ';
char accSrc = ' ';
char accDest = ' ';
double amount = 0;
BankAccount src = null;
do {
try{
// process JOptionPane input information
String input = JOptionPane
.showInputDialog("Please enter your transaction information: ");
Scanner s = new Scanner(input);
id = Integer.parseInt(s.next());
action = Character.toUpperCase((s.next().charAt(0)));
if (action == 'T') {
amount = s.nextDouble();
accSrc = s.next().charAt(0);
accDest = s.next().charAt(0);
} else if (action == 'G' || action == 'I') {
accSrc = s.next().charAt(0);
} else {
// if D,W
amount = s.nextDouble();
accSrc = s.next().charAt(0);
}
} catch (IOException e){
}
// taking action accordingly (T)ransfer, (D)eposit, (W)ithdraw, (I)nterest
if (action == 'T') {
(customer[id].getAccount(accSrc)).transfer(amount,
customer[id].getAccount(accDest));
} else if (action == 'G') {
System.out.println("The current balance on your " + accSrc
+ " account is "
+ customer[id].getAccount(accSrc).getBalance() + "\n");
} else if (action == 'D') {
(customer[id].getAccount(accSrc)).deposit(amount);
} else if (action == 'W') {
(customer[id].getAccount(accSrc)).withdraw(amount);
} else if (action == 'I') {
(customer[id].getAccount(accSrc)).computeInterest();
}
whichOption = JOptionPane
.showConfirmDialog(null , "Do you want to continue?");
System.out.println("The balance on " + customer[id].getName()
+ " auto account is " + customer[id].A.balance);
System.out.println("The balance on " + customer[id].getName()
+ " savings account is " + customer[id].S.balance);
System.out.println("The balance on " + customer[id].getName()
+ " checkings account is " + customer[id].C.balance);
System.out.println("The balance on " + customer[id].getName()
+ " loan account is " + customer[id].L.balance + "\n");
} while (whichOption == 0);
}
}

It is because none of the operations you perform inside try/catch throws IOException.
As per Scanner javadoc
Most of the Scanner class methods throws either FileNotFoundException (Which is not applicable in your case because not reading from file) (or) IllegalArgumentException (or) IllegalStateException
You need to change IOException to either of above exceptions (or) remove try/catch.

You can remove the IOException and the try catch since none of the statements inside the try catch is throwing this exception

Seems like nothing you are doing in that try block is throwing the IOException

No method call in that try block throws a IOException, that is why the catch is an unreachable code.
You can safely remove both the try and the catch, as that situation will never happen.

Your catch block is empty, indicating that you weren't really going to handle the exception, anyway. You probably had some code in there that made you catch it, but now you don't have it anymore. Just remove the entire surrounding try-catch and there will be no further problems.

try/catch block is empty and code is not throw IOException but it may throw other exceptions.