I am having a problem when i break out from remove part the code prints main menu options twice
There is no error in code and it runs properly but why does it print twice instead of once?
public void mainloop() {
for (int i = 0; i < 100; i++) {
String x;
System.out.println("Please Select your option");
System.out.println("............................");
System.out.println("1 ADD NAME AND NUMBER \n2 REMOVE NAME AND NUMBER \n3 SEARCH NAME AND NUMBER \n0 EXIT");
System.out.println("............................");
x = input.nextLine();
if (x.equalsIgnoreCase("0")) {
System.out.println("Thank you!");
break;
}
if (x.equalsIgnoreCase("1")) {
String Name;
String Number;
System.out.println("Please Enter your Name below");
Name = input.nextLine();
System.out.println("Please Enter your Number below");
Number = input.nextLine();
System.out.println("");
System.out.println("Your Name " + Name + " and Number " + Number + " has been saved!\n");
objectclass objectclassObject = new objectclass(Name, Number);
Test.add(objectclassObject);
}
if (x.equalsIgnoreCase("2")) {
System.out.println("-------ALL NAME AND NUMBERS-------");
System.out.println("");
for (int j = 0; j < Test.size();) {
objectclass p = Test.get(j++);
System.out.println(j + ". Name: " + p.getName() + " - " + p.getNumber());
}
for (int j = 0; j < Test.size(); j++) {
System.out.println("");
System.out.println("Enter Index number to remove Contact from Phonebook!");
int v = input.nextInt();
int temp = (v - 1);
if (v >= 1 && v <= Test.size()) {
System.out.println("Name: " + Test.get(temp).getName() + " And Number: " + Test.get(temp).getNumber() + " has been removed!!");
System.out.println("");
Test.remove(temp);
} else {
System.out.println("Please enter number properly!!");
}
break;
}
}
if (x.equalsIgnoreCase("3")) {
String y;
System.out.println("*** Enter your Name below for search ***");
y = input.nextLine();
for (objectclass p : Test) {
String z = p.getName();
if (z.equalsIgnoreCase(y)) {
System.out.println("Your Name is: " + p.getName() + "\nYour Number is: " + p.getNumber());
System.out.println("");
}
if (!z.equalsIgnoreCase(y)) {
System.out.println("Contact not found!!!");
}
}
}
}
}
}
System.out.println("Please Select your option");
System.out.println("............................");
System.out.println("1 ADD NAME AND NUMBER \n2 REMOVE NAME AND NUMBER \n3 SEARCH NAME AND NUMBER \n0 EXIT");
System.out.println("............................");
this prints twice :/~
If this prints twice, you went 2 times thru the loop. Try to display the variable 'x' after reading it. I bet you have extra empty strings between your legitimate input.
What happens is that nextInt() doesn't consume the newline. Therefore, the next time you read x you read the end of the line after the value v.
As mentioned by #Aeshang please use Switch instead of if.
Secondly
if (x.equalsIgnoreCase("2")) {
block does not end before
if (x.equalsIgnoreCase("3")) {
Your remove part also includes search part. Not sure if this will solve the problem but first correct these things and check your answer.
Related
public static void main(String[] args) {
Scanner input = new Scanner(System.in);
boolean start = true;
while(start)
System.out.printf("%70s %n", " ##### Zoos Australia ##### " + "\n");
System.out.printf("%57s %n", "Main Menu" + "\n");
System.out.printf("%72s %n", "Zoo has the following ticketing options:");
System.out.print("\n");
System.out.printf("%59s %n", "1 = Child (4-5 yrs)");
System.out.printf("%59s %n", "2 = Adult (18+ yrs)");
System.out.printf("%60s %n", "3 = Senior (60+ yrs)");
System.out.println("\n");
String choose1 = "";
String choose2 = "";
String choose3 = "";
String selected = "";
int option = 0;
{
System.out.print("Please select an option: ");
option = input.nextInt();
if (option == 1) {
choose1 = "Child";
selected = choose1;
} else if (option == 2) {
choose2 = "Adult";
selected = choose2;
} else if (option == 3) {
choose3 = "Senior";
selected = choose3;
}
}
// done
System.out.println("\n");
int price = 0;
int tickets = 0;
System.out.print("Enter the number of tickets: ");
tickets = input.nextInt();
if (selected == choose1) {
price = 10;
} else if (selected == choose2) {
price = 20;
} else if (selected == choose3) {
price = 15;
}
System.out.println("\n");
System.out.print("You are purchasing " + tickets + " " + selected + " tickets at " + "$" + price + " each!");
System.out.println("\n");
int confirm = 0;
System.out.print("Press 1 to confirm purchase: ");
confirm = input.nextInt();
if (confirm != 1) {
System.out.print("Incorrect Key. Please return to Main Menu");
System.out.println("\n");
} else {
break;
}
System.out.println("\n");
int total = tickets;
price = total * price;
System.out.print("Total amount for " + selected + " tickets: " + "$" + price);
System.out.println("\n");
String pick = "";
System.out.print("Do you wish to continue: ");
input.next();
System.out.println("\n");
if (pick == "no") {
System.out.print("Total amount payable is: " + "$" + price);
System.out.println("\n");
System.out.print("Have a nice day!");
System.out.println("\n");
}}}
Trying to do this at the end of the program where user is asked "Do you wish to continue" using a method or something but cant get it to work. Either the program returns to main menu only or the program ends and displays the total message "Total amount payable..." etc. I have tried using while with continue and break. Using boolean with true and false. But no luck. Thank you anyone that may be able to clear this up for me please.
First, you have to assign the users's input to a variable: pick = input.next(). After that, the problem is that you compare the user's input string with a "no" string by using == operator. When comparing reference types (objects) (and String is an object), in most cases == operator gives you an unpredictable result, because it compares the reference (address of an object in memory) and not the actual content. Please remember, that you always have to use the .equals() method instead. You also have to break from your loop, when the user's input is "no".
There is plenty of material concerning this issue. You can check, for instance, this one How do I compare strings in Java?
P.S. I quickly looked at the rest of your code and put some additional comments, which might help you to improve it. Good luck with learning Java!
Scanner input = new Scanner(System.in);
// boolean start = true; you don't need this line
while(true) { // 'true' condition makes it an infinite loop until you use break
// You also have to surround your while loop with curly braces,
// otherwise you fall into an infinite loop
System.out.printf("%70s %n", " ##### Zoos Australia ##### \n");
System.out.printf("%57s %n", "Main Menu\n");
System.out.printf("%72s %n", "Zoo has the following ticketing options: \n");
System.out.printf("%59s %n", "1 = Child (4-5 yrs)");
System.out.printf("%59s %n", "2 = Adult (18+ yrs)");
System.out.printf("%60s %n", "3 = Senior (60+ yrs)\n");
String choose1 = "";
String choose2 = "";
String choose3 = "";
String selected = "";
int option = 0;
System.out.print("Please select an option: ");
option = input.nextInt();
if (option == 1) {
choose1 = "Child";
selected = choose1;
} else if (option == 2) {
choose2 = "Adult";
selected = choose2;
} else if (option == 3) {
choose3 = "Senior";
selected = choose3;
}
System.out.println(); // "\n" is a redundant argument
int price = 0;
int tickets = 0;
System.out.print("Enter the number of tickets: ");
tickets = input.nextInt();
if (selected.equals(choose1)) { // you should never compare strings with == operator! Always use .equals() instead
price = 10;
} else if (selected.equals(choose2)) {
price = 20;
} else if (selected.equals(choose3)) {
price = 15;
}
System.out.println();
System.out.print("You are purchasing " + tickets + " " + selected + " tickets at " + "$" + price + " each!");
System.out.println();
int confirm = 0;
System.out.print("Press 1 to confirm purchase: ");
confirm = input.nextInt();
if (confirm != 1) {
System.out.print("Incorrect Key. Please return to Main Menu");
System.out.println("\n");
} else {
//break; you cannot use 'break' in the if statement! You have to figure out another way, how to handle an invalid input
}
System.out.println();
int total = tickets;
price = total * price;
System.out.print("Total amount for " + selected + " tickets: " + "$" + price);
System.out.println();
String pick = "";
System.out.print("Do you wish to continue: ");
pick = input.next(); // you have to assign the input to a variable
System.out.println();
if (pick.equals("no")) { // You have to ALWAYS use .equals() when comparing Strings or any other reference types! == works correctly only with primitive types
System.out.print("Total amount payable is: " + "$" + price);
System.out.println();
System.out.print("Have a nice day!");
System.out.println();
break; // you need to break from the loop in the end
}
}
}
Code for menu options won't loop, but has no errors. I intentionally wrote it similar to my while loop that loops just fine. I have to use only integers, and my instructor did tell me to turn my inputs into variables. Most of it isn't quite finished but I'm working on that at the same time as trying to figure all this out.
//Loop to check user input
num=-1;
while (num<0)
{
//Getting user entered interger
System.out.print("Please enter a positive number: ");
num = kb.nextInt();
//Ensuring positive interger
if (num >= 0)
{
System.out.println("You've entered the number " + num + ".");
}
else
{
System.out.println("Error! The number you've entered is not a valid interger.");
}
}
copy = num;
//Printing menu loop
copy2 = -1;
do
{
//Menu making
System.out.println(" ");
System.out.println("1. Enter a new number.");
System.out.println("2. Print the number of odd digits, even digits, and zeros in the interger.");
System.out.println("3. print if the number is light or heavy.");
System.out.println("4. Print the prime numbers between 2 and the interger (inclusive).");
System.out.println("5. Quit the program.");
System.out.println(" ");
System.out.print("Please enter your menu choice: ");
choice = kb.nextInt();
copy2 =choice;
//Checking entry
if (0<copy2 && copy2<=5)
{
System.out.println("You chose option " +copy2+".");
}
//Option one
if (copy2 == 1)
{
System.out.print("Will work on soon.");
}
//Option two
if (copy2 == 2)
{
oddNum=0;
evenNum=0;
zero=0;
while (copy>0)
{
if (copy %10==0)
{
zero++;
}
else if (copy %2==1)
{
evenNum++;
}
else
{
oddNum++;
}
}
copy = copy/10;
System.out.println("Even numbers: " + evenNum+
"\nOdd numbers: "+ oddNum +
"\nZeros: " +zero );
}
//Option three
if (copy2 == 3)
{
loh = 0;
do
{
System.out.println("To check if your number is light or heavy, we need a second interger.");
System.out.print("Please enter a second positive interger: ");
loh = kb.nextInt();
if (loh >= 0)
{
numWeight = ((loh +copy)/2);
//Test num weight
System.out.println("Check: " +numWeight);
if (numWeight > copy)
{
System.out.print("The number " + copy + " compared to the number "
+ loh + " is a heavy number.");
}
else
{
System.out.print("The number " + copy + " compared to the number "
+ loh + " is a light number.");
}
}
if (loh < 0)
{
System.out.println("Error! The number you've entered is not a valid interger.");
}
}while (loh <=0);
}
//Option four
if (copy2 ==4)
{
primeNumbers = 0;
for (int i=1; i<=copy; i++)
{
int counter = 0;
for(int prime = i; prime>=1; prime--)
{
if (i%prime==0)
{
counter = counter +1;
}
}
if (counter==2)
{
primeNumbers = primeNumbers + i;
}
}
System.out.println("Prime numbers from 2-"+copy+" are: ");
System.out.println(primeNumbers);
}
//Option five
else
{
System.out.print("Error! Please enter a valid menu option.");
}
}while (copy2 <0 && copy2 >=6);
}//End main
}//End class
You should use switch case for your purpose. nested if/else isn't good idea for menu options but switch case make it more clear to understand what are you going to do.
switch (num) {
case c1:
statements // they are executed if variable == c1
System.out.println("1. Enter a new number.");
break;
case c2:
System.out.println("2. Print the number of odd digits, even digits, and zeros in the interger.");
statements // they are executed if variable == c2
break;
case c3:
case c4:
statements // they are executed if variable == any of the above c's
break;
. . .
default:
statements // they are executed if none of the above case is satisfied
break;
}
My teacher wants us to make a program that counts the total number of votes for two candidates from a variable number of precincts. So the user inputs the candidates’ names as strings and is then prompted to enter the number of precincts prior to entering the votes for each precinct. What I am having trouble with is that I have to use an array to keep each precinct's vote total. Then after all of that is done I have to keep a running total of the votes for each candidate after each precinct is completed and who is currently leading and by how much. I have already begun my program but I am honestly just lost as to where to go from here, and I know that what I have in my arrays so far is not correct.
import java.util.*;
public class Voting
{
public static void main (String [] args)
{
Scanner scan = new Scanner(System.in);
int rerun;
int rerun2;
while (rerun == 1)
{
System.out.print("Name of candidate 1: ");
candidate1 = scan.next();
System.out.print("Name of candidate 2: ");
candidate2 = scan.next();
System.out.print("\nPlease enter amount of precincts: ");
presincts = scan.nextInt();
System.out.print("\n Please enter amount of votes for candidate 1: ");
votes1 = scan.nextInt();
System.out.print("\n Please enter amount of votes for candidate 2: ");
votes2 = scan.nextInt();
while (rerun2 == 1 && precincts >= 0 && votes1 >= 0 && votes2 >= 0)
{
int[] votes1 = new int[precincts];
for(int i = 0; i < votes1.length; i++)
{
votes1[i] = int [i];
System.out.println ("\n" + votes1);
}
int[] votes2 = new int[precincts];
for(int i = 0; i < votes2.length; i++)
{
votes2[i] = int [i];
System.out.println ("\n" + votes2);
}
}
}
}
}
I don't know what the function of rerun is so I've left it out of this answer.
First thing you're going to want to do is initialize your variables at the start of your class:
String candidate1;
String candidate2;
int precincts;
int vote1;
int vote2;
int total1;
int total2;
int[] votes1;
int[] votes2;
Note you had a typo in precincts
Then you need to get the name of the candidates and the number of precincts (you've done this correctly already):
Scanner scan = new Scanner(System.in);
System.out.print("Name of candidate 1: ");
candidate1 = scan.next();
System.out.print("Name of candidate 2: ");
candidate2 = scan.next();
System.out.print("\nPlease enter amount of precincts: ");
precincts = scan.nextInt();
Then you need to iterate through the number of precincts, and get the number of votes for each candidate from each precinct. You can do this by initializing an empty array which will keep the votes stored (eg, the votes for the first candidate in precinct 1 will be stored in votes1[0]). Additionally, the easiest way to keep a running total is to use a separate variable total1 and total2:
total1 = 0;
total2 = 0;
votes1 = new int[precincts];
votes2 = new int[precincts];
for (int i = 0; i < precincts; i++) {
System.out.print("\nPlease enter amount of votes for candidate 1 in precinct " + (i + 1) + ": ");
vote1 = scan.nextInt();
votes1[i] = vote1;
total1 = total1 + vote1;
System.out.print("\nPlease enter amount of votes for candidate 2 in precinct " + (i + 1) + ": ");
vote2 = scan.nextInt();
votes2[i] = vote2;
total2 = total2 + vote2;
}
From inside the for loop you can do things like print the current total votes for a candidate:
System.out.println(candidate1 + " has " + total1 + " votes in total");
And print out who is the current leader and by how many votes:
if (total1 > total2) {
System.out.println(candidate1 + " is winning by " + (total1-total2) + " votes");
} else {
System.out.println(candidate2 + " is winning by " + (total2-total1) + " votes");
}
I have a program that asks the user their name etc. Then it asks how many times do you want the numbers to loop (so my program generates 3 random numbers between 7 and 13 and if it adds up to 31 they are the winner) and my issue is that I only want the last printed number to count towards if the player wins or looses, the other numbers are just for show or tease i guess. the problem is that regardless towards if the player wins or looses, the losing statement always prints out. Below is my entire code.
import java.util.InputMismatchException;
import java.util.Scanner;
import java.io.IOException;
import java.util.Random;
public class StringVariables {
public static void main(String[] args) throws NumberFormatException,
IOException {
// user inputs their name in this section
Scanner user_input = new Scanner(System.in);
//enter their first name
String first_name;
System.out.print("Enter Your First Name: ");
while
(!user_input.hasNext("[A-Za-z]+")) {
System.out.println("Please only enter alphabet characters. Try again.");
user_input.next();
}
first_name = user_input.next();
//enter their last name
String last_name;
System.out.print("Enter Your Last Name: ");
while
(!user_input.hasNext("[A-Za-z]+")) {
System.out.println("Please only enter alphabet characters. Try again.");
user_input.next();
}
last_name = user_input.next();
//full name printed together
String full_name;
full_name = first_name + " " + last_name;
System.out.println(full_name + " Is Now Playing");
// this is the shuffle portion as well as something to see if a number
int numShuffles = -1;
while (numShuffles < 0) {
System.out.println("How many times do you want the numbers shuffled? ");
try {
numShuffles = user_input.nextInt();
} catch (InputMismatchException inputException) {
System.out.print("Please enter a valid number. \n");
//this is the buffer that resets if the user types a letter instead of a number, or any other character
user_input.next();
}
}
// here is going to be the loop for shuffles
// we are now going to generate their random number and add a delay
// after completing their name fields
delay(3000);
System.out
.println(" You will be given " + numShuffles + " hand(s) of 3 random numbers between 7-13" );
delay(2000);
System.out
.println(" Then, the computer will add the random numbers and if it is equal to 31, you win!");
/*
* end of explanation of the game, next i will create a new screen with
* the user's name and numbers
*/
delay(4000);
// printing 25 blank lines
for (int i = 0; i < 25; i++)
System.out.println(" ");
System.out.println("User playing: " + full_name);
System.out.println("Number of times shuffled: " + numShuffles);
System.out.println("Your lucky numbers are...");
// random number generator
Random random = new Random();
while (true) {
// the shuffle loop
Arraylist numberStore = new Arraylist();
boolean isWinner = false;
for (int i = 0; i < numShuffles; i++) {
int num1 = 7 + random.nextInt(7);
int num2 = 7 + random.nextInt(7);
int num3 = 7 + random.nextInt(7);
System.out.println(num1 + " + " + num2 + " + " + num3 + " = " + (num1 + num2 + num3));
numberStore.add(num1 + num2 + num3);
int lastNumber = (numberStore.size() - 1);
if (lastNumber == 31) {
isWinner = true;
System.out.println("Congratulations !! You are the Lucky Winner !!!!");
break;
//if you loose every shuffle
}
}
if (!isWinner) {
System.out.println("Better Luck Next Time");
}
// play again prompt
System.out
.println(" Do you want to play again? (If you do enter y or yes) \n To exit press any other key ");
String input = user_input.next();
if (!"y".equalsIgnoreCase(input) && !"yes".equalsIgnoreCase(input)) {
break;
}
}
// if pressed y or yes the program will run again with the same number of shuffles entered from before
user_input.close();
}
// delay field
public static void delay(int millis) {
try {
Thread.sleep(millis);
} catch (InterruptedException exp) {
// delay field
}
}
}
int lastNumber = (numberStore.size() - 1);
if (lastNumber == 31) {
you probably want something like
int lastNumber = numberStore.get(numberStore.size() - 1);
if (lastNumber == 31) {
to verify that is the error try to change that line to
int lastNumber = num1 + num2 + num3;
Edit based on further messages:
Looks like what you really want is this:
for (int i = 0; i < numShuffles; i++) {
int num1 = 7 + random.nextInt(7);
int num2 = 7 + random.nextInt(7);
int num3 = 7 + random.nextInt(7);
System.out.println(num1 + " + " + num2 + " + " + num3 + " = " + (num1 + num2 + num3));
numberStore.add(num1 + num2 + num3);
int lastNumber = num1 + num2 + num3;
boolean lastShuffle = (i == (numShuffles - 1));
if (lastShuffle) {
if (lastNumber == 31) {
System.out.println("Congratulations !! You are the Lucky Winner !!!!");
} else {
System.out.println("Better Luck Next Time");
}
}
}
// play again prompt
System.out
.println(" Do you want to play again? (If you do enter y or yes) \n To exit press any other key ");
String input = user_input.next();
if (!"y".equalsIgnoreCase(input) && !"yes".equalsIgnoreCase(input)) {
break;
}
Just a general suggestion: avoid to use break if possible, it makes control flow hard to follow and is not a good programming practice.
Several points to make here. One, your code is quite messy and hard to read. It's helpful when you're asking for help (and in general anyway) to properly indent your code. This is good practice and if you do other languages like Python can help you out a lot. Also, why do a check for !isWinner? Scrap the isWinner variable altogether and just check for the number equalling 31 and then have an else statement for the losing statement. Like this:
if (lastNumber == 31) {
System.out.println("Congratulations !! You are the Lucky Winner !!!!");
break;
//if you loose every shuffle
}
else {
System.out.println("Better Luck Next Time");
}
Also, take some steps to find the error. Print out each number as you get it, and use
int lastNumber = num1 + num2 + num3;
instead of
int lastNumber = (numberStore.size() - 1);
Also for anybody else compiling this, it's ArrayList and not Arraylist... just a little slip.
Sorry, I may have to say that your codes are a kind of mess up. a small factory with the solution you ask, hope it can be a little help to you
public static void main(String[] args) throws NumberFormatException,
IOException {
Scanner user_input = new Scanner(System.in);
String full_name = registeGamePlayer(user_input);
int numShuffles = initGame(user_input);
showTheGameInfo(full_name, numShuffles);
runningGame(user_input, numShuffles);
user_input.close();
}
/**
* #param user_input
* #param numShuffles
*/
private static void runningGame(Scanner user_input, int numShuffles) {
// random number generator
Random random = new Random();
while (true) {
// the shuffle loop
boolean isWinner = false;
for (int i = 0; i < numShuffles; i++) {
int num1 = 7 + random.nextInt(7);
int num2 = 7 + random.nextInt(7);
int num3 = 7 + random.nextInt(7);
int amount = num1 + num2 + num3;
System.out.printf("%d + %d + %d = %d \n", num1,num2,num3,amount);
if (amount == 31) {
isWinner = true;
System.out.println("Congratulations !! You are the Lucky Winner !!!!");
break;
// if you loose every shuffle
}
}
if (!isWinner) {
System.out.println("Better Luck Next Time");
}
// play again prompt
System.out.println(" Do you want to play again? (If you do enter y or yes) \n To exit press any other key ");
String input = user_input.next();
if (!"y".equalsIgnoreCase(input) && !"yes".equalsIgnoreCase(input)) {
break;
}
}
}
/**
* #param full_name
* #param numShuffles
*/
private static void showTheGameInfo(String full_name, int numShuffles) {
// printing 25 blank lines
for (int i = 0; i < 25; i++)
System.out.println(" ");
System.out.println("User playing: " + full_name);
System.out.println("Number of times shuffled: " + numShuffles);
System.out.println("Your lucky numbers are...");
}
// delay field
public static void delay(int millis) {
try {
Thread.sleep(millis);
} catch (InterruptedException exp) {
// delay field
}
}
private static String registeGamePlayer(Scanner user_input){
String first_name;
System.out.print("Enter Your First Name: ");
while (!user_input.hasNext("[A-Za-z]+")) {
System.out
.println("Please only enter alphabet characters. Try again.");
user_input.next();
}
first_name = user_input.next();
// enter their last name
String last_name;
System.out.print("Enter Your Last Name: ");
while (!user_input.hasNext("[A-Za-z]+")) {
System.out
.println("Please only enter alphabet characters. Try again.");
user_input.next();
}
last_name = user_input.next();
// full name printed together
String full_name;
full_name = first_name + " " + last_name;
System.out.println(full_name + " Is Now Playing");
return full_name;
}
private static int initGame(Scanner user_input){
// this is the shuffle portion as well as something to see if a number
int numShuffles = -1;
while (numShuffles < 0) {
System.out.println("How many times do you want the numbers shuffled? ");
try {
numShuffles = user_input.nextInt();
} catch (InputMismatchException inputException) {
System.out.print("Please enter a valid number. \n");
// this is the buffer that resets if the user types a letter
// instead of a number, or any other character
user_input.next();
}
}
// here is going to be the loop for shuffles
// we are now going to generate their random number and add a delay
// after completing their name fields
delay(3000);
System.out.println(" You will be given " + numShuffles + " hand(s) of 3 random numbers between 7-13");
delay(2000);
System.out.println(" Then, the computer will add the random numbers and if it is equal to 31, you win!");
/*
* end of explanation of the game, next i will create a new screen with
* the user's name and numbers
*/
delay(4000);
return numShuffles;
}
I have the following piece of code where I'm trying to get the user to only enter integers; if a string is entered then it would display a system out error message "please only enter numbers" and then it would show the "Enter your ID#:" again. I tried using the try/catch method but was not using it correctly -- still a beginner. I know I can use the "NumberFormatException" but not sure where. Can anyone help? Thanks!
//Get Customer ID and Account Number
do
{ System.out.print("Enter your ID#: ");
custid = Integer.parseInt(input.readLine());
System.out.print("Enter your Account Number#: ");
custacctnum = Integer.parseInt(input.readLine());
//validate the choice
for(int i=0; i<people.length; i++)
{ if ((people[i].custid == custid) && (people[i].custacctnum == custacctnum))
{ match = true;
System.out.println("Welcome " +people[i].firstname+ " to JJ Dealership!");
for(int p=0; p<cluster.length; p++)
System.out.println(+(p+1)+ ": " +cluster[p].year+"," +cluster[p].make+ "," +cluster[p].model);
System.out.println(people[i].firstname+ ", what color car would you like?");
break;
}
}
if (!match)
{ System.out.println("Invalid ID");
} while (!(match));
Exceptions should be for exceptional circumstances. I suggest you use a Scanner and hasNextInt() to just continue when it isn't an int. That is make a Scanner like,
Scanner input = new Scanner(System.in);
and then something like this would work,
do {
System.out.print("Enter your ID#: ");
if (!input.hasNextInt()) {
System.out.printf("%s is not an int.%n", input.nextLine());
continue;
}
custid = input.nextInt();
System.out.print("Enter your Account Number#: ");
custacctnum = input.nextInt();
if (!input.hasNextInt()) {
System.out.printf("%s is not an int.%n", input.nextLine());
continue;
}
If you really want to use try-catch it should look something like,
do
{
try {
System.out.print("Enter your ID#: ");
custid = Integer.parseInt(input.readLine());
System.out.print("Enter your Account Number#: ");
custacctnum = Integer.parseInt(input.readLine());
//validate the choice
for(int i=0; i<people.length; i++)
{ if ((people[i].custid == custid) &&
(people[i].custacctnum == custacctnum))
{ match = true;
System.out.println("Welcome " +people[i].firstname
+ " to JJ Dealership!");
for(int p=0; p<cluster.length; p++)
System.out.println("" + (p+1) + ": " +cluster[p].year+","
+ cluster[p].make+ "," +cluster[p].model);
System.out.println(people[i].firstname
+ ", what color car would you like?");
break;
}
}
} catch (NumberFormatException nfe) {
nfe.printStackTrace();
}
} while (!(match));
#Elliott Frisch, I "played" around with it before I saw your answer and figured out how to use the try/catch. It was fairly simple, but I will look at the other option that you posted. With the updated code below when the user enters a string, it will display the error message and then take them to the "Enter your ID#" line to try again.
Thank you all so much for the quick response.
do
{
try{
System.out.print("Enter your ID#: ");
custid = Integer.parseInt(input.readLine());
System.out.print("Enter your Account Number#: ");
custacctnum = Integer.parseInt(input.readLine());
//validate the choice
for(int i=0; i<people.length; i++)
{ if ((people[i].custid == custid) && (people[i].custacctnum == custacctnum))
{ match = true;
System.out.println("Welcome " +people[i].firstname+ " to JJ Dealership!");
for(int p=0; p<cluster.length; p++)
System.out.println(+(p+1)+ ": " +cluster[p].year+"," +cluster[p].make+ "," +cluster[p].model);
System.out.println(people[i].firstname+ ", what color car would you like?");
break;
}
}
if (!match)
{ System.out.println("Invalid ID");
}
} catch (NumberFormatException e)
{System.out.println ("Error! Please enter a number!");}
} while (!(match));