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no luck with reading integers from file in arraylist

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Join Date: Oct 2004

Posts: 26

Reputation: SyLk is an unknown quantity at this point

Solved Threads: 0

SyLk

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no luck with reading integers from file in arraylist

Sep 7th, 2008

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();
		}

	}

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Join Date: Jun 2008

Posts: 973

Reputation: Alex Edwards is a jewel in the rough

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Alex Edwards Alex Edwards is offline

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Posting Shark

Re: no luck with reading integers from file in arraylist

Sep 7th, 2008

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

 Help with Code Tags 
 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();
		}
	}
}