Trying To Read A Text File Into An Array

Question

I have a project which I need help fixing my code to read a text file into an array. My coding can open the file but gives me "NoSuchElementException" error when I get to this line, String contactInfo = inFS.nextLine().trim(); If I remake out the inner loop, it goes into an infinite loop.

Here are criteria for this project, my current coding and some sample data. Any suggestions are appreciated.

Method readContactsFromFile

Declared as public static method with a Scanner as an input parameter
Use FileInputStream to read the file, note you will need throws IOException in the method declaration
Returns a String multi-dimensional array that contains MAX_SIZE (30) rows and MAX_FIELDS (3) columns
Ask user for the name of the file where the contacts are stored. Your program should add the “.txt” to the name.

The method will read the data from the text file “?????.txt”, each line in the file contains a first name, last name, and phone number separated by a comma.  Hint: After reading each line, use the split function. The split function will read each field separated by a comma and place it into an array String contactInfo = input.nextLine().trim(); String[] contactInfoArray = contactInfo.split(",");

public static String[][] readContactsFromFile(Scanner scanner) throws IOException {
   String [][] contactsArray = new String[MAX_SIZE][MAX_FIELDS];
   String inputFileName;
   String filename;
   FileInputStream contactsStream = null; // File input stream
   Scanner inFS = null;                   // Scanner object

   // Try to open file
   System.out.print("Enter file name: ");
   inputFileName = scanner.next();

   filename= inputFileName+".txt";
   try {
       contactsStream = new FileInputStream(filename);
   } catch (FileNotFoundException e) {

       e.printStackTrace();
   }
   inFS = new Scanner(contactsStream);

   while(inFS.hasNextLine()){
       for(int row=0;row<MAX_SIZE;row++) {
           String contactInfo = inFS.nextLine().trim();
           String[] contactInfoArray = contactInfo.split(",");

           for(int column=0;column<MAX_FIELDS;column++) {
               contactsArray [row][column] = contactInfoArray[column];
           }
       }  

   }
    return contactsArray;

}

Sample data from text file(without the additional line separating the records):

Emily,Watson,913-555-0001

Madison,Jacobs,913-555-0002

Joshua,Cooper,913-555-0003

Brandon,Alexander,913-555-0004

Emma,Miller,913-555-0005

did you try to [debug](https://stackoverflow.com/questions/25385173/what-is-a-debugger-and-how-can-it-help-me-diagnose-problems?noredirect=1&lq=1) the thing? You can do it with any IDE. — Curiosa Globunznik, Nov 30 '19 at 04:20
Yes. That is how I discovered the two different issues I'm using Eclipse as my IDE — kstoneman84, Nov 30 '19 at 05:03

Curiosa Globunznik · Accepted Answer · 2019-11-30T05:15:39.640

1

Looks like your file has less lines than MAX_SIZE. If you remove for(int row=0;row<MAX_SIZE;row++), create a variable row and increment it in each iteration that would be one thing. You'd need to limit the loop further too while(inFS.hasNextLine() && row < MAX_SIZE) about.

edited Nov 30 '19 at 05:15

answered Nov 30 '19 at 04:18

Curiosa Globunznik

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Thanks gurioso. I modified my coding to be: int row=0; while(inFS.hasNextLine() && row < MAX_SIZE) { String contactInfo = inFS.nextLine().trim(); String[] contactInfoArray = contactInfo.split(","); for(int column=0;column – kstoneman84 Nov 30 '19 at 06:06

score 0 · Answer 2 · answered Nov 30 '19 at 05:34

I noticed your code could be cleaned up with some help, as there is a lot of extra stuff, which may be causing confusion.

Scanner sc = new Scanner("Test.txt");
    String line;
    while(!(line = sc.nextLine()).equals("")){
        String[] elems = line.split(",");

        //implement the rest of the code
}

This will be able to do whatever you are trying to do with the code.

As pointed out, you read the line twice. Here, the

while(!(line = sc.nextLine()).equals(""))

takes care of that, by calling first storing the nextLine in the variable line, and then checking for null equality with null.

Trying To Read A Text File Into An Array

2 Answers2