Object linked list

Question

Hi am trying to create a linked list out of an object i have called ClassID.
I have a Link class (that creates a node correct?):
import java.io.*;
public class Link
     public ClassID id;
    public Link next;
     public Link(ClassID inID)
          this(inID, null);
    public Link(ClassID inID, Link next)
        id = inID;
        next = next;;
     public void displayLink() // display ourself
          id.toString();
} // end class LinkIf it does create node then I have a class called LinkList with the following insert method:
private Link first; // ref to first link on list
// insert at start of list
     public void insertFirst(Link id)
     { // make new link
          Link newLink = new Link(id);
          newLink.next = first; // newLink --> old first
          first = newLink; // first --> newLinkBut it doesnt seem to be working, could someone help me.
Thanks
Phil
Edited by: The_One on Sep 13, 2008 1:49 AM

Answer 1

I dont think its doing it properly. Iv tried goign through it but cant find the problem. Might be a problem with displaylist
Let me paste all my classes:
LINK METHOD:
import java.io.*;
public class Link
     public ClassID id;
    public Link next;
     public Link(ClassID inID)
          this(inID, null);
    public Link(ClassID inID, Link next)
        id = inID;
        next = next;;
     public void displayLink() // display ourself
          id.toString();
} // end class LinkLINKLIST METHOD:
class LinkList
     private Link first; // ref to first link on list
     public LinkList() // constructor
          first = new Link(null); // no items on list yet
     public boolean isEmpty() // true if list is empty
          return (first==null);
     // insert at start of list
     public void insertFirst(ClassID id)
     { // make new link
          Link newLink = new Link(id);
          newLink.next = first; // newLink --> old first
          first = newLink; // first --> newLink
public void displayList()
          System.out.print("List (first-->last): ");
          Link current = first; // start at beginning of list
          while(current != null) // until end of list,
               current.displayLink(); // print data
               current = current.next; // move to next link
          System.out.println("");
................. SOME MORE METHODS..........MAIN METHOD:
import java.io.*;
public class SortListApp
    public static void main(String[] args)
     BufferedReader inputStream = null;
     LinkList list = new LinkList();
     try
          inputStream = new BufferedReader(new FileReader("data.txt"));
           String inName;
          int inIDNum;
          int inACNum;
          long inTime;
          int inTransmode;
          //while ((inName = (inputStream.readLine()) ) != null)
               inName = inputStream.readLine();
               inIDNum = Integer.parseInt(inputStream.readLine());
               inACNum = Integer.parseInt(inputStream.readLine());
               inTime = Long.parseLong(inputStream.readLine());
               inTransmode = Integer.parseInt(inputStream.readLine());
               list.insertFirst(new ClassID(inName, inIDNum, inACNum, inTime, inTransmode));                    
          list.displayList();
          //System.out.println("Printed to file");
          //list.sort();
          inputStream.close();
     catch (IOException error)
          System.out.println("Error in file");
}Edited by: The_One on Sep 13, 2008 2:41 AM