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Thread: Can scanner read the specified line?

  1. #1
    Member ice's Avatar
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    Default Can scanner read the specified line?

    Hi guys

    Can Scanner read the specified line from user's input?

    For example, I want Scanner to find the 50th line of input and read it only, not from the first line, how to do that?

    Many Thanks


  2. #2
    mmm.. coffee JavaPF's Avatar
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    Default Re: Can scanner read the specified line?

    Hello ice,

    The problem with the Scanner is, as soon as the user presses enter, it takes that as the input.
    There isn't a way to move to the next line without pressing enter.

    This is assuming you are taking user input from the console though.
    If you were reading in a file with the Scanner class, this wouldn't be a problem.
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    mmm.. coffee JavaPF's Avatar
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    Default Re: Can scanner read the specified line?

    You could possibly do something like this. As an example, it will take in user input and print out the 10th line.

    import java.util.Scanner;
     
    public class ScannerTest {
     
    	/**
    	 * JavaProgrammingForums.com
    	 */
    	public static void main(String[] args) {
     
    		Scanner sc = new Scanner(System.in);
    		System.out.println("Enter something:");
     
    		int count = 1;
     
    		while (sc.hasNext()) {
    			String ignore = sc.nextLine();
    			count++;
    			if (count == 10) {
    				String keep = sc.nextLine();
    				System.out.println("This is the 10th line: " + keep);
    				break;
    			}
    		}
    	}
    }
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  4. The Following User Says Thank You to JavaPF For This Useful Post:

    ice (January 27th, 2011)

  5. #4
    Member ice's Avatar
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    Default Re: Can scanner read the specified line?

    Thank you so much JavaPF!! ..especially the example you provided.
    If you were reading in a file with the Scanner class, this wouldn't be a problem.
    , you mean Scanner can read the specified line from a file? If so, then how to do that?  
    Last edited by ice; January 26th, 2011 at 05:59 PM.

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    Crazy Cat Lady KevinWorkman's Avatar
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    Default Re: Can scanner read the specified line?

    Quote Originally Posted by ice View Post
    Thank you so much JavaPF!! ..especially the example you provided.
    , you mean Scanner can read the specified line from a file? If so, then how to do that?  
    He posted a great way to do it. What he meant was, with a file, you don't have to wait for the user to press enter.
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    Default Re: Can scanner read the specified line?

    oh ok I see now.
    Thanks KevinWorkman.

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    Default Re: Can scanner read the specified line?

    No problem. So did you get it all figured out?
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  9. #8
    mmm.. coffee JavaPF's Avatar
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    Default Re: Can scanner read the specified line?

    Glad I could help.

    May be worth taking a look at - http://www.javaprogrammingforums.com...ner-class.html
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