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Problems With Linked List

Posted on 2004-03-26
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Last Modified: 2010-03-31
//im creating 3 mailboxes and trying to add them to the post office linked list. but everytime i create a new mailbox it overwrites all of the previous mailboxes
//

  public static PostOffice myPO;
    public static void main(String[] args)
  {
    MultiThreadedServer multiThreadedServer1 = new MultiThreadedServer();
 
  myPO = new PostOffice();
    System.out.println("PostOffice created.");

    Mailbox mb1 = new Mailbox("lauren", "test1");
    System.out.println("Mailbox mb1 created: " + mb1.getUser() + "-" + mb1.getPassword());
    myPO.add(mb1);
    System.out.println("Mb1 added to PO");
    printMailboxInfo();

    Mailbox mb2 = new Mailbox("a", "z");
    System.out.println("Mailbox mb2 created: " + mb2.getUser() + "-" + mb2.getPassword());
    myPO.add(mb2);
     System.out.println("Mb2 added to PO");
     printMailboxInfo();

    Mailbox mb3 = new Mailbox("chris", "test33");
    System.out.println("Mailbox mb3 created: " + mb3.getUser() + "-" + mb3.getPassword());
    myPO.add(mb3);
    System.out.println("Mb3 added to PO");
    printMailboxInfo();

package server;
import java.util.*;

public class PostOffice
{

  public static LinkedList mailboxList ;
  public PostOffice()
  {
    System.out.println("in POSTOFFICE CONSTRUCTOR!!");
    mailboxList = new LinkedList();
  }

  public void add(Mailbox box)
  {
    System.out.println("In PO: adding mailbox: " + box.getUser() + "-" + box.getPassword());
    this.mailboxList.addFirst(box);
  }
}
public class Mailbox
{
  private static String user, password;

  private static LinkedList emailList  ;

  public Mailbox(String uname, String pass)
  {
    this.user = uname;
    this.password = pass;
   emailList = new LinkedList();


  }

  public void addEmailToBox(Email mail)
  {
    System.out.println("In Mailbox, adding mail: " + mail.toString());
    this.emailList.add(mail);
  }
  public String getUser()
  {
    return this.user;
  }
  public String getPassword()
  {
    return this.password;
  }
  public LinkedList getEmailList()
  {
    return this.emailList;
  }
}
0
Comment
Question by:tricks801
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4 Comments
 
LVL 92

Accepted Solution

by:
objects earned 2000 total points
ID: 10690965
thats because your using static variables.
try:

 public LinkedList mailboxList ;

  private String user, password;

  private LinkedList emailList  ;
0
 
LVL 92

Expert Comment

by:objects
ID: 10690970
All instances of the same class share the one static var.
0
 

Author Comment

by:tricks801
ID: 10690991
whoops. thanks
0
 
LVL 92

Expert Comment

by:objects
ID: 10690998
0

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