no luck with reading integers from file in arraylist

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can someone help me understand what i'm doing wrong here. attempted to run, program builds but no output is generated and the compiler does'nt generate an error message.

thank you all.

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import java.util.Scanner;
import java.io.*;
import java.util.ArrayList;


public class arrayManipulator 
{

                 public static void main(String[] args) throws IOException
	{
		ArrayList<Integer> myArray = new ArrayList<Integer>();
		
		Scanner s = null;
		try 
		{
			s = new Scanner(new BufferedReader (new FileReader("usrnames.txt")));
				while(s.hasNext())
				{
					if(s.hasNextInt())
					{
						for(int i=0; i<myArray.size(); i++)
						{
						myArray.set(i, s.nextInt());
						System.out.print(" "+myArray.get(i));
						}
					}
				}
		}
		finally
		{ s.close();
		}

	}

SyLk

Reputation Points: 10

Solved Threads: 0

Light Poster

Offline

27 posts
since Oct 2004

Permalink

Sep 7th, 2008

Re: no luck with reading integers from file in arraylist

Here's a way to filter out what you need without worrying about hideous "blocks" from the Scanner class--

java Syntax (Toggle Plain Text)
import java.util.Scanner;
import java.io.*;
import java.util.ArrayList;
 
public class arrayManipulator{
        public static void main(String... args) throws IOException{
		ArrayList<Integer> myArray = new ArrayList<Integer>(0);
		BufferedReader s = null;
		try{
			s = new BufferedReader(new FileReader("C:/Documents and Settings/Mark/My Documents/usrnames.txt"));
				while(s.ready()){
					String value = "" + (char)s.read();
					try{
						Integer x = Integer.parseInt(value);
						myArray.add(x);
					}catch(Exception e){
						continue;
					}
				}
				System.out.println(myArray);
		}finally{ 
			s.close();
		}
	}
}
import java.util.Scanner;
import java.io.*;
import java.util.ArrayList;

public class arrayManipulator{
        public static void main(String... args) throws IOException{
		ArrayList<Integer> myArray = new ArrayList<Integer>(0);
		BufferedReader s = null;
		try{
			s = new BufferedReader(new FileReader("C:/Documents and Settings/Mark/My Documents/usrnames.txt"));
				while(s.ready()){
					String value = "" + (char)s.read();
					try{
						Integer x = Integer.parseInt(value);
						myArray.add(x);
					}catch(Exception e){
						continue;
					}
				}
				System.out.println(myArray);
		}finally{ 
			s.close();
		}
	}
}

Alex Edwards

Reputation Points: 392

Solved Threads: 108

Posting Shark

Offline

971 posts
since Jun 2008

Permalink

Sep 8th, 2008

Re: no luck with reading integers from file in arraylist

Thanks Alex

SyLk

Reputation Points: 10

Solved Threads: 0

Light Poster

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27 posts
since Oct 2004

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