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Printing user input in array says null

I am trying to print user input from an array to display in java. When i run this, it just prints out "null" for each amount no matter what the user inputs. I am a beginner at java and want to learn more about arrays, and I can't seem to figure this out.
String itemAmount = ss.getInputString("How many items?");
int amount = Integer.parseInt(itemAmount);
String[] Items = new String[amount];
for (int i = 0; i < Items.length; i++) {
ss.getInputString("Please enter items?");
}
for (int i = 0; i < Items.length; i++) {
ss.println((Items[i]));
}
Also, how would i be able to print the items, for example user inputs 3 items -> "Eggs", "Bacon", "Tomato" how would I print this to show in a line separated by commas.

I'm not sure what gt is, but since you're using it this way
String itemAmount = gt.getInputString("How many items?");
I guess it's some sort of wrapper around the standard input.
You can use it the same way to populate an array, one item at a time.
for (int i = 0; i < Items.length; i++) {
Item[i] = gt.getInputString("Please enter items?");
}
You seem to be able to use the array in the other loop, so I'll assume you don't need further explanation.
Then to print them on a single line, separated by a comma you can use the join method of String (note: you need to convert your array to a List, first)
String joinedString = String.join(", ", Arrays.asList(Items));

I think you are checking the length of wrong array/string in second for loop. It should be Items.length not Appliances.length

char digit to integer conversion [duplicate]

This question already has answers here:
Using charAt method, won't add them as an Int, and wont print as string. Will explain better
(4 answers)
Using charAt in System.out.println displays integer?
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Why does this code print the ASCII value instead of the character
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(1 answer)
Closed 5 years ago.
I'm getting the user to enter a string of numbers, then a for loop should pick out each number from the string and add it to an ArrayList. I'm sure someone can help me out fairly quickly
My problem is as follows. When I print out all the values in the ArrayList, It is printing out much higher numbers e.g. 1234 = 49 50 51 52.
I think what is happening is that it is printing out the ASCII values rather than the numbers themselves. Can anyone spot where and why this is happening?
I have tried changing the int variable barcodeNumberAtI to a char, which yields the same result.
Apologies for lack of comments but this was only supposed to be a quick program
int tempNewDigit;
String barCode, ans;
int barcodeNumberAtI;
ArrayList <Integer> numbers = new ArrayList <Integer>();
public void addNumbers(){
Scanner s = new Scanner(System.in);
do{
System.out.println("Please enter a 12 digit barcode\n");
barCode = s.nextLine();
for(int i = 0; i < barCode.length(); i++){
barcodeNumberAtI = barCode.charAt(i);
System.out.println(barcodeNumberAtI);
numbers.add(barcodeNumberAtI);
}
System.out.print("Would you like to add another? y/n\n");
ans = s.nextLine();
} while (!ans.equals("n"));
}
public void displayNumbers(){
for(int i = 0; i < numbers.size(); i++){
System.out.print(numbers.get(i));
}
}

Happens at this line: barcodeNumberAtI = barCode.charAt(i);
barCode.charAt(i) returns a char which is converted to a int by using its ASCII value.
Use this instead:
barcodeNumberAtI = Character.digit(barCode.charAt(i), 10);
What Character.digit does is converting its first argument from the type char to the corresponding int in the radix specified by the second argument.
Here's a link to the documentation

Check String is in a range of numbers Java

Trying to design a simple lottery program. Everything works except checking if the numbers entered are between 1 to 59.
Exercise says the numbers must be stored in a String variable.
so
if(num<0 || num>59) //wont work for me
Tried making another variable
int numConverted = Integer.parseInt(num)
We haven't covered converting String to int in class though so I don't think this is what expected. Got confused trying that way anyway so probably this is wrong.
Here is the code I have currently.
{
Scanner scan = new Scanner(System.in);
String num=""; //num variable is empty untill user inputs numbers
for(int i =0; i<6; i++)
{
System.out.println("Enter your number between 1-59");
num = num +" "+ scan.nextLine();
}
System.out.println("Ticket printed £2. Your numbers are " + num);
}

In your posted code it's obvious that you want the User to supply 6 specific numerical values. These values are appended to the String variable named num (space delimited). You need to obviously do a few things here:
1) Make sure the value supplied by the user is indeed a numerical value;
2) Make sure the numerical values supplied fall within the minimum and maximum scope of the lottery itself (which you have stated is: 1 to 59);
3) Make sure the number entered by the User hasn't been supplied already.
You've been tasked to store the entered values into a String data type variable and that is all fine but at some point you want to carry out value comparisons to make sure that all the entered values actually play within the limits of the lottery.
When the User completes his/her entries, you end up with a space delimited string held in the num string variable. You now need to make sure that these values entered are indeed....numbers from 1 to 59 and none contain alpha characters.
In my opinion (and this is only because you need to store entered values into a String variable), it's best to use your String variable to gather User input, then test the input to make sure it is indeed a string representation of an actual integer number. Once this is established then we test to make sure if falls within the value min/max limits (1-59). Now we need to test to make sure the number entered hasn't already been entered before for this ticket.
Of course with each test described above, if one fails then the User should be prompted to re-enter a proper value. You can do this by utilizing a while loop. Plenty examples of this in StackOverflow but here's a quick example:
Scanner scan = new Scanner(System.in);
String ticketNumbers = "";
for(int i = 0; i < 6; i++) {
Boolean isOK = false;
while (!isOK) {
System.out.println("\nPlease enter your desired 6 ticket numbers:\n"
+ "(from 1 to 59 only)");
String num = scan.nextLine();
//Is the string entered an actual integer number?
//We use the String.matches() method for this with
//a regular expression.
if(!num.matches("\\d+")) {
System.out.println("You must supply a numerical value! "
+ "Try Again...");
continue;
}
if (ticketNumbers.contains(num + " ")) {
System.out.println("The number you supplied has already been chosen!"
+ " Try Again...");
continue;
}
if (Integer.parseInt(num) >= 1 && Integer.parseInt(num) <= 59) {
ticketNumbers+= num + " ";
isOK = true;
}
else {
System.out.println("The number you supply must be from "
+ "1 to 59! Try Again...");
}
}
}
System.out.println("Ticket printed £2. Your numbers are " + ticketNumbers);

How about -
if(Integer.parseInt(num) < 0 || Integer.parseInt(num) > 59)
This should work, place it after the input.
If it works, please mark this as correct, I need the rep!!!

Easy way would be add available numbers (suppose it wont grow more than 60. You can use a loop to add to this as well)
String numbers[] = {"1","2","3", "..."};
Then inside the loop
Arrays.asList(numbers).contains(num);
You can remove prefixing zero in order avoid conflicts with values like '02'
Here everything is String related.

If you don't want to explicitly convert to int, you could use a regular expression.
if (num.matches("[1-5]?[0-9]")) {
...
This checks whether the String consists of (1) maybe a digit from 1 to 5, followed by (2) definitely a digit from 0 to 9. That'll match any number in the range 0-59.
If you've got a whole series of numbers separated by spaces, you could expand this to cover a whole series like this.
if (num.matches("([1-5]?[0-9]\\s+)*[1-5]?[0-9]")) {
This matches any number of repetitions (including zero) of "a number followed by spaces", followed by a single repetition without a space. The "\\s" means "any whitespace character", the "+" after it means "one or more of what precedes", and the "*" means "zero more of what precedes" - which in this case is the term in parentheses.

Oh I see what you are trying to do
This is what you want
Scanner scan = new Scanner(System.in);
String allNums = "";
for(int i =0; i<6; i++)
{
System.out.println("Enter your number between 1-59");
int num = scan.nextInt();//Take the number in as an int
if(num >0 && num < 59)//Check if it is in range
{
allNums += num + " ";//if it is add it to a string
}
else
{
System.out.println("Number not in range");
i--;//go back one iteration if its not in range
}
}
System.out.println("Ticket printed £2. Your numbers are " + allNums);

convert String to arraylist of integers using wrapper class

Im trying to write a program that takes a string of user inputs such as (5,6,7,8) and converts it to an arrayList of integers e.g. {5,6,7,8}. I'm having trouble figuring out my for loop. Any help would be awesome.
String userString = "";
ArrayList<Integer> userInts = new ArrayList<Integer>();
System.out.println("Enter integers seperated by commas.");
userString = in.nextLine();
for (int i = 0; i < userString.length(); i++) {
userInts.add(new Integer(in.nextInt()));
}

If your list consists of single-digit numbers, your approach could work, except you need to figure out how many digits there are in the string before allocating the result array.
If you are looking to process numbers with multiple digits, use String.split on the comma first. This would tell you how many numbers you need to allocate. After than go through the array of strings, and parse each number using Integer.parseInt method.
Note: I am intentionally not showing any code so that you wouldn't miss any fun coding this independently. It looks like you've got enough knowledge to complete this assignment by reading through the documentation.

Lets look at the lines:
String userString = ""
int[] userInt = new int[userString.length()];
At this point in time userString.length() = 0 since it doesnt contain anything so this is the same as writing int[] userInt = new int[0] your instantiating an array that cant hold anything.
Also this is an array not an arrayList. An arrayList would look like
ArrayList<Integer> myList = new ArrayList()<Integer>;

I'm assuming the in is for a Scanner.
I don't see a condition to stop. I'll assume you want to keep doing this as long as you are happy.
List<Integer> arr = new ArrayList<Integer>();
while(in.hasNext())
arr.add(in.nextInt());
And, say you know that you will get 10 numbers..
int count = 10;
while(count-- > 0)
arr.add(in.nextInt());

Might I suggest a different input format? The first line of input will consist of an integer N. The next line contains N space separated integers.
5
3 20 602 3 1
The code for accepting this input in trivial, and you can use java.util.Scanner#nextInt() method to ensure you only read valid integer values.
This approach has the added benefit of validate the input as it is entered, rather than accepting a String and having to validate and parse it. The String approach presents so many edge cases which need to be handled.

Giving input separated by spaces

Input:
1 10
How can I provide a space between two inputs so that compiler can take both the inputs differently.
I tried to use
st1=in.nextInt();
in.next();
st2=in.nextInt();

Simply remove the in.next(); call. nextInt() already "ignores" whitespaces. And there is no need to create an array by using split() and to convert the number "manually". Just let the Scanner handle this by using nextInt() like you do already:
Scanner s = new Scanner("1 10 9 5");
while(s.hasNextInt()) {
int number = s.nextInt();
System.out.println(number);
}
The good thing about that is, that you won't get a NumberFormatException like in the other answers if the user does not provide numbers (e.g. a b c).

The following line will give you a String array containing the two numbers as strings:
String[] numbersFromUser = in.nextLine().split(" ");
Assuming that the user properly formats the input.
This would of course also work for a number of arguments greater than 2.
You can then go on to convert numbersFromUser[0] and numbersFromUser[1] into the int values you need:
int st1 = Integer.valueOf(numbersFromUser[0]).intValue();
int st2 = Integer.valueOf(numbersFromUser[1]).intValue();

Use:
data = line.split("\s");
first = data[0];
second = data[1];
third = data[2];
System.out.println(first)
System.out.println(second);
System.out.println(third);
Input:
1 5 6
Output:
1
5
6