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Why am I getting an InputMismatchException with?

I created a Scanner in java to read through a file of data regarding a city. The file is formatted as such:
Abbotsford,2310,2
Adams,1967,1
Algoma,3167,2
When reading through the file, I get an InputMismatchException when scanning the last item on each line (This item needs to be an int).
public void fileScanner(File toScan) throws FileNotFoundException {
Scanner sc = new Scanner(toScan);
sc.useDelimiter(",");
System.out.println(sc.next());
System.out.println(sc.nextInt());
System.out.println(sc.nextInt());
Any ideas as to why? I'd imagine it has something to do with my use of the "," delimiter.

You are using only one delimiter i.e. , but your file contains \r or \n so try to use multiple delimiters. Also, use a loop to read the entire file:-
Scanner sc = new Scanner(toScan);
sc.useDelimiter(",|\\r\\n");
while (sc.hasNext()) {
System.out.println(sc.next());
System.out.println(sc.nextInt());
System.out.println(sc.nextInt());
}
OUTPUT:-
Abbotsford
2310
2
Adams
1967
1
Algoma
3167
2

The delimiter you're using is comma(,)
The system looks for the next comma, which comes only after Adams. So the input for the system looks like 2 Adams which is obviously not an Int , rather a String and hence the inputMisMatch.
If you make your data something like below, your code would work great.
Abbotsford,2310,2,
Adams,1967,1,
Algoma,3167,2,
Also I see there's no loop to read all the data. Your code will read just the first line.

Java: Parse lines from files

I am in need of some ideas. I have a file with some information like this:
AAA222BBB%
CC333DDDD%
EEEE444FF%
The '%' sign is like an indicator of "end of line"
I would like to read every line, and then parse it to fit a certain format (4 letters, 3 digits and 4 letters again) - So if it looks like the above, it should insert a special sign or whitespace to fill, like this:
AAA-222BBB-%
CC--333DDDD%
EEEE444FF--%
My first and immediate idea was to read every line as a string. And then some huge if-statement saying something like
For each line:
{
if (first symbol !abc...xyz) {
insert -
}
if (second symbol !abc...xyz) {
insert -
}
}
However, I am sure there must be a more elegant and effective way, do to a real parsing of the text, but I'm not sure how. So if anyone has a good idea please enlighten me :-)
Best

My first advice is to read this other post (nice explanation of scanner and regex):
How do I use a delimiter in Java Scanner?
Then my solution (sure it is the the cleverest, but it should work)
For each line:
{
Scanner scan = new Scanner(line);
scan.useDelimiter(Pattern.compile("[0-9]"));
String first = scan.next();
scan.useDelimiter(Pattern.compile("[A-Z]"));
String second = scan.next();
scan.useDelimiter(Pattern.compile("[0-9]"));
String third = scan.next();
scan.close();
System.out.println(addMissingNumber(first, 4) + addMissingNumber(second, 3) + addMissingNumber(third, 4));
}
//For each missing char add "-"
private static String addMissingNumber(String word, int size) {
while (word.length() < size) {
word = word.concat("-");
}
return word;
}
The output: "AAA-222BBB-"

Java - Reading in value from text

OK so I have read plenty of examples on here dealing with reading in lines from a text file and splitting them up but im not quite sure I understand how to do it in my situation. I have a file that is basically separated into three columns as follows:
START 5000
FIND A
PLUS B
SAVE C
STOP
A, INT 69
B, INT -420
C, CRAZY 008484342
What I am trying to do is read in this .txt file containing the above information. I figured reading in the file line by line would be best, then splitting it into the correct columns. The problem that I am having is the fact that the 1st column is not always here. It is an optional one. If they were all filled in, im almost positive I could just use use something like
String[] array1 = myLine.split(",");
Another idea I had was to split the line based on ,'s then split the line again based on " " but im not exactly sure how to do this. Maybe somthing like
String[] array1 = myLine.split(",");
String[] array2 = array1[1].split(" ");
Also, is there any way to just read in the file and store each row into like (String, String String) then just check for ints vs strings? Maybe in a try catch? or like:
Scanner input = new Scanner(File);
while(input.hasNext()){
String str = input.next();
try{
b = Integer.parseInt(str);
}
I am not sure if this is as hard as a task as im making it but maybe so... Any help with this topic would be appreciated.
After looking over some more code, I have the following to start:
public static void main(String[] args) {
String file ="TEST.txt";
try{
FileReader input = new FileReader(file);
BufferedReader bufferReader = new BufferedReader(input);
String line;
while ((line = bufferReader.readLine()) != null) {
// Is this where I would attempt to split the lines?
System.out.println(line);
}
bufferReader.close();
}catch(Exception e){
System.out.println("Error while reading file line by line:" + e.getMessage());
}
}
}
So with this, I am successfully reading in the file and displaying the information back to the output console. Now for separating the lines... Ill be posting my work as I go, any help and or suggestions would be appreciated! Also thank you to those who have already commented with helping to split the stings, ill be attempting this now!

You can combine both expressions and only checked the array's length. e.g.:
String[] array = line.trim().split("[, ]+");
switch(array.length) {
case 2:
// do something
break;
case 3:
// do something
break;
default:
// something wrong
break;
}
The trim() in the line is for avoid empty string in the first element array.

Use split(" +") which will split on any numbers of spaces. This works because split handles regex. If you want to split on any type of whitespace you can also use split("\\s+). After you get the array check if it has 2 or 3 elements and handle it accordingly.

Well ... I don't have the time yet for a long answer. But I'd recommend you to read a little bit about regular expressions (RegEx) and how it is used in java ... I am sure this will help you with this problem and a huge amount of future problems like this ...
Try this: http://www.vogella.com/articles/JavaRegularExpressions/article.html ... of this http://docs.oracle.com/javase/tutorial/essential/regex/ ... if the first one does not help ;)

How can i split the user's input with tokens?

i need your advise in order to do something ... i want to take the user's input line as i already do in my program with scanner ... but i want to split each command(word) to tokens .... i do not know how to do that , till now i was playing with substring but if the users for example press twice the space-bar button everything is wrong !!!!!
For example :
Please insert a command : I am 20 years old
with substring or .split(" ") , it runs but think about having :
Please insert a command : I am 20 years old
That is why i need your advice .... The question is how can i split the user's input with tokens.

Well, you need to normalize you string line before splitting it to tokens. A simplest way is to remove repeated whitespace characters:
line = line.replaceAll("\\s+", " ");
(this will also replace all tabs to a single " ").

Use the StringTokenizer class. From the API :
"[It] allows an application to break a string into tokens... A
StringTokenizer object internally maintains a current position within
the string to be tokenized."
The following sample code from the API will give you an idea:
StringTokenizer st = new StringTokenizer("this is a test");
while (st.hasMoreTokens()) {
System.out.println(st.nextToken());
}
It produces the following result:
this
is
a
test

Okay, so the code that I have made is going to ask you for to insert a command, it is then going to take your command and then split it around any number of spaces (due to the Regex). It then saves these words, numbers, speech marks etc. as tokens. You can then manipulate each word in the for loop.
import java.util.Scanner;
public class CommandReaderProgram{
public static void main(String[] args){
Scanner userInput = new Scanner(System.in);
System.out.println("Please insert a command:");
String temp = userInput.nextLine();
while(temp != null){
String [] tokens = temp.split("\\s+");
for(String word : tokens){
System.out.print(word);
System.out.print(" ");
}
break;
}
System.out.print("\n");
}
}
To test that each word, number and speech mark has actually been saved as a token, change the character in the System.out.print(" "); code to anything. e.g System.out.print(""); or
System.out.print("abcdefg"); and it will put this data between each token, to prove that the tokens are indeed separate.
Unfortunately I am unable to call the token array outside of the for loop at the moment, but will let you know when I figure it out.
I'd like to hear what type of program you are trying to make as I think we are both trying to make something very similar.
Hope this is what you are looking for.
Regards.

How do I change the delimiter from a text file?

Let's say I got a textfile.txt that I want to read from. This is the text in the file:
23:years:old
15:years:young
Using the useDelimiter method, how can I tell my program that : and newlines are delimiters? Putting the text in one line and using useDelimter(":"); works. The problem is when I got several lines of text.
Scanner input = new Scanner(new File("textfile.txt));
input.useDelimiter(:);
while(data.hasNextLine()) {
int age = input.nextInt();
String something = input.next();
String somethingelse = input.next();
}
Using this code I will get an inputMisMatch error.

Try
scanner.useDelimiter("[:]+");
The complete code is
Scanner scanner = new Scanner(new File("C:/temp/text.txt"));
scanner.useDelimiter("[:]+");
while (scanner.hasNext()) {
System.out.println(scanner.next());
}
The output is
23
years
old
15
years
young

Use this code
Scanner input;
String tokenizer[];
try {
input = new Scanner(new File("D:\\textfile.txt"));
input.useDelimiter("\\n");
while(input.hasNextLine()) {
tokenizer = input.next().split(":");
System.out.println(tokenizer[0]+" |"+tokenizer[1]+" | "+tokenizer[2]);
}
}catch(Exception e){}
It will give you output like
23 |years | old
15 |years | young

You have two ways to do this:
Concatenate the string to make it one line.
delimit "newline" first, then delimit ":" each return string token.

If all you want is to get everything split up all at once then I guess you can use
useDelimiter(":\\n")
That should split on both : and newspace but it is not the most efficient way of processing data, especially if each line of text is set out in the same format and represents a complete entry. If that is the case then my suggestion would be to only split on a new line to begin with, like this;
s.useDelimiter("\\n");
while(s.hasNext()){
String[] result = s.next.split(":");
//do whatever you need to with the data and store it somewhere
}
This will allow you to process the data line by line and will also split it at the required places. However if you do plan on going through line by line I recommend you look at BufferedReader as it has a readLine() function that makes things a lot easier.

As long as all the lines have all three fields you can just use input.useDelimiter(":\n");

you probably wants to create a delimiter pattern which includes both ':' and newline
I didn't test it, but [\s|:]+ is a regular expression that matches one or more whitespace characters, and also ':'.
Try put:
input.useDelimiter("[\\s|:]+");