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Using a Scanner to Extract Line-Delimited Data

I am fetching data from a file. I am having problems using delimiters when reading a file.

My file is ordered like this:

0    Name    0
1    Name1   1

The structure is an integer, tab (\ t), string, tab (\ t), another integer, and then a newline (\ n).

I tried using a compound delimiter as stated in this question: Java - using multiple delimiters in a scanner

However, I still get an InputMismatch exception when I run the following code:

while(readStations.hasNextLine()) { 
 327    tempSID = readStations.nextInt();
 328    tempName = readStations.next();
 329    tempLine = readStations.nextInt();
        //More code here
}

It throws this error on line 2 of the above code ... I'm not sure why and help would be appreciated, thanks.

The current output is executed as such for the code:

Exception in thread "main" java.util.InputMismatchException
    ...stuff...
    at Metro.declarations(Metro.java:329)
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2 answers


The newline is most likely causing you problems. try it



    public class TestScanner {

        public static void main(String[] args) throws IOException {
            try {   
                Scanner scanner = new Scanner(new File("data.txt"));   
                scanner.useDelimiter(System.getProperty("line.separator"));   
                while (scanner.hasNext())  {  
                    String[] tokens = scanner.next().split("\t");
                    for(String token : tokens) {
                        System.out.print("[" + token + "]");
                    }
                    System.out.print("\n");
                }
                scanner.close();  
            } 
            catch (FileNotFoundException e) {   
                e.printStackTrace();  
            }
       }
    }
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I think that when the scanner strips the input this way, you can only use input.next () and not the following int: or keep the same type.



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