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

Answer 1

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.

Answer 2

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.