How do I make this progam in java into a linked list?

// the Node class

class Node

{

private int data;

private Node link;

// constructor

public Node()

{

this.data = 0;

this.link = null;

}

// accessor and mutator for the data component

public int getData()

{

return this.data;

}

public void setData(int data)

{

this.data = data;

}

// accessor and mutator for the link component

public Node getLink()

{

return this.link;

}

public void setLink(Node link)

{

this.link = link;

}

}

// the List class

public class List

{

public static final int MAX_SIZE = 50;

private Node head;

private Node tail;

private Node curr;

private int num_items;

// constructor

// remember that an empty list has a "size" of -1 and its "position" is at -1

public List()

{

num_items= -1;

head = new Node();

curr=head;

}

// copy constructor

// clones the list l and sets the last element as the current

public List(List l)

{

}

// navigates to the beginning of the list

public void First()

{

}

// navigates to the end of the list

// the end of the list is at the last valid item in the list

public void Last()

{

}

// navigates to the specified element (0-index)

// this should not be possible for an empty list

// this should not be possible for invalid positions

public void SetPos(int pos)

{

}

// navigates to the previous element

// this should not be possible for an empty list

// there should be no wrap-around

public void Prev()

{

}

// navigates to the next element

// this should not be possible for an empty list

// there should be no wrap-around

public void Next()

{

}

// returns the location of the current element (or -1)

public int GetPos()

{

}

// returns the value of the current element (or -1)

public int GetValue()

{

}

// returns the size of the list

// size does not imply capacity

public int GetSize()

{

}

// inserts an item before the current element

// the new element becomes the current

// this should not be possible for a full list

public void InsertBefore(int data)

{

}

// inserts an item after the current element

// the new element becomes the current

// this should not be possible for a full list

public void InsertAfter(int data)

{

}

// removes the current element (collapsing the list)

// this should not be possible for an empty list

public void Remove()

{

}

// replaces the value of the current element with the specified value

// this should not be possible for an empty list

public void Replace(int data)

{

}

// returns if the list is empty

public boolean IsEmpty()

{

}

// returns if the list is full

public boolean IsFull()

{

}

// returns if two lists are equal (by value)

public boolean Equals(List l)

{

}

// returns the concatenation of two lists

// l should not be modified

// l should be concatenated to the end of *this

// the returned list should not exceed MAX_SIZE elements

// the last element of the new list is the current

public List Add(List l)

{

}

// returns a string representation of the entire list (e.g., 1 2 3 4 5)

// the string "NULL" should be returned for an empty list

public String toString()

{

}

}