Using delimiter when reading a file

Question

I have little experience using delimiters and i need to read a text file that stores several objects whose data is stored in single lines separate by commas (\",\"). The sep

Answer 1

You should be using next(); where you are using nextLine();

Have a look at the tutorial: http://docs.oracle.com/javase/tutorial/essential/io/scanning.html

Notice the lines:

try {
   s = new Scanner(new BufferedReader(new FileReader("xanadu.txt")));

   while (s.hasNext()) {
   System.out.println(s.next());
}

Answer 2

One issue is:

while(read.hasNext())
   {
       title = read.nextLine();
       category = read.nextLine();
       runningTime = read.nextLine();

hasNext()

Returns true if this scanner has another token in its input. Not entire line. You need to use hasNextLine()

You are doing nextLine() three times. I think what you need to do is, read the line and the split the line.

Answer 3

All of the answers above are right and actually the same. However, one important point everybody should remember that the Scanner has a buffer size of only 1024. That means if the length of the delimited text is more, the parsing will stop.

So, a little enhancement to the given solution, use BufferedReader instead of directly passing the file to the Scanner. Example:

    BufferedReader in = new BufferedReader(new FileReader("datafile.txt"), 16*1024);
    Scanner read = new Scanner(in);
    read.useDelimiter(",");
    String title, category, runningTime, year, price;

    while(read.hasNext())
    {
        title = read.next();
        category = read.next();
        runningTime = read.next();
        year = read.next();
        price = read.next();
        System.out.println(title + " " + category + " " + runningTime + " " + year + " " + price + "\n"); //just for debugging
    }
    read.close();

Answer 4

You can also use a String.split() function to convert the string to an array of strings, then iterate over each of them for your values.

How to convert comma-separated String to ArrayList? see this for more details.

Answer 5

I think you want to call .next() which returns a String instead of .nextLine(). Your .nextLine() call is moving past the current line.

Scanner read = new Scanner (new File("datafile.txt"));
   read.useDelimiter(",");
   String title, category, runningTime, year, price;

   while(read.hasNext())
   {
       title = read.next();
       category = read.next();
       runningTime = read.next();
       year = read.next();
       price = read.next();
     System.out.println(title + " " + category + " " + runningTime + " " + year + " " + price + "\n"); //just for debugging
   }
   read.close();

Answer 6

Use read.next() instead of read.nextLine()

   title = read.next();
   category = read.next();
   runningTime = read.next();
   year = read.next();
   price = read.next();