[Reza_]

hi guys!

I have four different classes; one is main class which contain a array of names now i want to make a linked list ( reference-based implementation ) using node class, ListInterface and ListReferenceBased class. I don`t know how to pass my array to these classes.

can anyone help me with this plzzzzz ?

public class Node {
  private Object item;
  private Node next;
 
  public Node(Object newItem) {
     item = newItem;
    next = null;
  } // end constructor
 
  public Node(Object newItem, Node nextNode) {
    item = newItem;
    next = nextNode;
  } // end constructor
 
  public void setItem(Object newItem) {
    item = newItem;
  } // end setItem
 
  public Object getItem() {
    return item;
  } // end getItem
 
  public void setNext(Node nextNode) {
    next = nextNode;
  } // end setNext
 
  public Node getNext() {
    return next;
  } // end getNext
} // end class Node 
 

// ****************************************************
// Reference-based implementation of ADT list.
// ****************************************************
public class ListReferenceBased implements ListInterface {
  // reference to linked list of items
  private Node head;
  private int numItems; // number of items in list
  HandlePersonalData data;
 
  public ListReferenceBased() {
    numItems = 0;
    head = null;
 
  }  // end default constructor
 
  public boolean isEmpty() {
    return numItems == 0;
  }  // end isEmpty
 
  public int size() {
    return numItems;
  }  // end size
 
  private Node find(int index) {
  // --------------------------------------------------
  // Locates a specified node in a linked list.
  // Precondition: index is the number of the desired
  // node. Assumes that 1 <= index <= numItems+1
  // Postcondition: Returns a reference to the desired
  // node.
  // --------------------------------------------------
    Node curr = head;
    for (int skip = 1; skip < index; skip++) {
      curr = curr.getNext();
    } // end for
    return curr;
  } // end find
 
  public Object get(int index)
                throws ListIndexOutOfBoundsException {
    if (index >= 1 && index <= numItems) {
      // get reference to node, then data in node
      Node curr = find(index);
      Object dataItem = curr.getItem();
      return dataItem;
    }
    else {
      throw new ListIndexOutOfBoundsException(
                "List index out of bounds on get");
    } // end if
  } // end get
 
  public void add(int index, Object item)
                  throws ListIndexOutOfBoundsException {
    if (index >= 1 && index <= numItems+1) {
      if (index == 1) {
        // insert the new node containing item at
        // beginning of list
        Node newNode = new Node(item, head);
        head = newNode;
      }
      else {
        Node prev = find(index-1);
        // insert the new node containing item after
        // the node that prev references
        Node newNode = new Node(item, prev.getNext());
        prev.setNext(newNode);
      } // end if
      numItems++;
    }
    else {
      throw new ListIndexOutOfBoundsException(
                "List index out of bounds on add");
    } // end if
  }  // end add
 
  public void remove(int index)
                     throws ListIndexOutOfBoundsException {
    if (index >= 1 && index <= numItems) {
      if (index == 1) {
        // delete the first node from the list
        head = head.getNext();
      }
      else {
        Node prev = find(index-1);
        // delete the node after the node that prev
        // references, save reference to node
        Node curr = prev.getNext();
        prev.setNext(curr.getNext());
      } // end if
      numItems--;
    } // end if
    else {
      throw new ListIndexOutOfBoundsException(
                "List index out of bounds on remove");
    } // end if
  }   // end remove
 
  public void removeAll() {
    // setting head to null causes list to be
    // unreachable and thus marked for garbage
    // collection
    head = null;
    numItems = 0;
  } // end removeAll
 
} // end ListReferenceBased 
 

/ ********************************************************
// Interface ListInterface for the ADT list.
// *********************************************************
public interface ListInterface {
  public boolean isEmpty();
  public int size();
  public void add(int index, Object item) 
                  throws ListIndexOutOfBoundsException,
                         ListException;
  public Object get(int index) 
                  throws ListIndexOutOfBoundsException;
  public void remove(int index) 
                  throws ListIndexOutOfBoundsException;
  public void removeAll();
}  // end ListInterface 
 

[King Coder]

But why would you pass arrays to these classes? Your constructors take Objects! Are you wanting a linked list where each element is an array

[jfulton]

Do you want to convert an Array to a LinkedList?

(Sorry if my Java coding is a little rusty )

//...myArray defined above...
LinkedList myList = new ListReferenceBased();
for (int i=0; i<myArray.length; i++) {
     /**
      * I think your implementation of LinkedList.add() is a little off
      * Generally the first element in a collection has index=0
      */
     myList.add(i+1, myArray[i]);
}
//...continue code...