package lists;
/*
 * ADT List
 * --------
 *
 * A List is a sequential structure that is either empty or it has a
 * sequence of nodes such that one node is the first, one node is the 
 * last, and each node except the last has a unique successor. Finally,
 * one node in a non-empty list is designated as the current node.
 * 
 * The list supports the following operations:
 * 
 *    List               - makes an empty list
 *    
 *    boolean isEmpty()  - checks if list is empty
 *    boolean isFull()   - checks if List if full
 *    boolean isFirst()  - checks if current is the first
 *    boolean isLast()   - checks if current is the last
 *    int getSize()      - returns number of elements in the list
 *    
 *    void first()       - makes current the first
 *    void next()        - makes current the successor of current
 *    
 *    void add(Object obj) - adds obj to the list
 *    void delete()        - removes current object from list
 *  
 *    void set(Object obj  - changes current object to obj
 *    Object get()         - returns object at current position
 */
public interface ADTList
{
    /* PRE/POST ...
     */
    public abstract boolean isEmpty();
    public abstract boolean isFull();
    public abstract boolean isFirst();
    public abstract boolean isLast();
    public abstract int getSize();
    public abstract void first();
    public abstract void next();
    public abstract void add(Object obj);
    public abstract void delete();
    public abstract void set(Object obj);
    public abstract Object get();
}