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Thread: Object creation from a input file and storing in an Array list

  1. #1
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    Red face Object creation from a input file and storing in an Array list

    ok, so i am a complete java noob and would be incredibly grateful if someone could show me how to create objects from a file and store them in an arraylist

    below is what i have so far
    import java.util.*;
    import java.io.*;
     
    public class People {
     
    	private String userName;
     
     
    	public People (String User)
    { 
    		userName = User;
     
    }
     
    	static ArrayList <People> Users = new ArrayList <People>();
     
    	public static void main(String[] args) 
    {
     
     
    		try 
    { 
     
    			File file1 = new File ("people.txt");
    			Scanner Filereader1 = new Scanner (file1);
    			while (Filereader1.hasNextLine())
     
     
    { 				
    				String Name = Filereader1.nextLine();
     
    				People User = new People(Name);
    				Users.add(User);
     
     
    }
     
    			System.out.println(Users);
     
    } 			
     
    		catch (FileNotFoundException e) 
    {
     
    			System.out.println("error" + e);
    }
     
     
     
     
     
     
     
    	}
     
    }
    Last edited by LabX; May 14th, 2009 at 03:26 AM.


  2. #2
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    Default Re: creating objects from file input and storing in arraylist

    You should be able to just use add(obj) rather than add(index, obj).

    Other than that can you please explain your problem as I cannot really see anything wrong with it, although does your ArrayList Really want to be static?

    Chris

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    Default Re: creating objects from file input and storing in arraylist

    what i want to do is to read input from a text file and create user objects from it

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    Default Re: creating objects from file input and storing in arraylist

    nvm i think i got it

    error was i was not using capital letters when executing it in dos
    AAHRHHAHRAHARHRAH

    2 hours wasted
    :'-(
    Last edited by LabX; May 14th, 2009 at 03:45 AM.

  5. #5
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    Default Re: creating objects from file input and storing in arraylist

    Hello LabX and welcome to the Java Programming Forums

    Does this work as expected?

    import java.util.*;
    import java.io.*;
     
    public class People {
     
        static ArrayList<String> Users = new ArrayList<String>();
     
        public static void main(String[] args) {
     
            try {
                File file1 = new File("people.txt");
                Scanner Filereader1 = new Scanner(file1);
                while (Filereader1.hasNextLine()) {
                    int i = 0;
                    String Name = Filereader1.next();
                    Users.add(i, Name);
                    i++;
                }
     
                Object[] elements = Users.toArray();
                for (int a = 0; a < elements.length; a++) {
                    System.out.println(elements[a]);
                }
     
            }
     
            catch (FileNotFoundException e) {
                System.out.println("error" + e);
            }
     
        }
     
    }
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