structure
Class OrderedList

java.lang.Object
  |
  +--structure.AbstractStructure
        |
        +--structure.OrderedList

All Implemented Interfaces:

OrderedStructure, Structure

public class OrderedList

extends AbstractStructure

implements OrderedStructure

A class that implements a collection of values that are kept in order. Base values must be comparable. Unlike Lists there is no notion of head or tail.

Example Usage:

To determine the effect of the original Starwars™ movie on the careers of its stars, we could place ComparableAssociations between each star's name and the number of movies they have been in since Starwars™ into an ordered vector and print our the results, as follows:

 public static void main(String[] argv){
	//instantiate an ordered vector
	OrderedList v = new OrderedList();
	
	//add the cast members of the original star wars along with
	//the number of films in which the have subsequently appeared
	v.add(new ComparableAssociation(new Integer(12),"Sir Alec Guiness"));
	v.add(new ComparableAssociation(new Integer(24),"Carrie Fisher"));
	v.add(new ComparableAssociation(new Integer(28),"Harrison Ford")); 
	v.add(new ComparableAssociation(new Integer(28),"Mark Hamill"));

	//print out the results
	for(Iterator i = v.iterator(); i.hasNext();){
	    ComparableAssociation actor = (ComparableAssociation)i.next();
	    System.out.println(actor.getValue() + " has been in " + 
			       actor.getKey() + " movies since Star Wars"); 
	}
   }
 

See Also:

Vector

Field Summary

protected int	count Number of elements in list
protected SinglyLinkedListElement	data Pointer to the smallest element, maintained as a singly linked list
protected Comparator	ordering The ordereding used to arange the values

Constructor Summary

OrderedList()
Construct an empty ordered list

OrderedList(Comparator ordering)
Construct an empty ordered list with alternative ordering

Method Summary

void	add(Object value) Add a value to the ordered list, keeping values in order
void	clear() Remove all the elements from the ordered list
boolean	contains(Object value) Determine if the ordered list contains a value
boolean	isEmpty() Determine if the list is empty
Iterator	iterator() Construct an iterator for traversing elements of ordered list in ascending order
Object	remove(Object value) Remove a value from the ordered list.
int	size() Determine the number of elements in the list
String	toString() Generate string representation of the ordered list

Methods inherited from class structure.AbstractStructure

elements, hashCode, values

Methods inherited from class java.lang.Object

, clone, equals, finalize, getClass, notify, notifyAll, registerNatives, wait, wait, wait

Methods inherited from interface structure.Structure

elements, values

Field Detail

data

protected SinglyLinkedListElement data

Pointer to the smallest element, maintained as a singly linked list

count

protected int count

Number of elements in list

ordering

protected Comparator ordering

The ordereding used to arange the values

Constructor Detail

OrderedList

public OrderedList()

Construct an empty ordered list

OrderedList

public OrderedList(Comparator ordering)

Construct an empty ordered list with alternative ordering

Parameters:

ordering - the Comparator to be used in comparison

Method Detail

clear

public void clear()

Remove all the elements from the ordered list

Specified by:

clear in interface Structure

Postcondition:

the ordered list is empty

add

public void add(Object value)

Add a value to the ordered list, keeping values in order

Specified by:

add in interface Structure

Parameters:

value - The value to be added to the list

Precondition:

value is non-null

Postcondition:

value is added to the list, leaving it in order

contains

public boolean contains(Object value)

Determine if the ordered list contains a value

Specified by:

contains in interface Structure

Overrides:

contains in class AbstractStructure

Parameters:

value - The value sought in the list

Precondition:

value is a non-null comparable object

Postcondition:

returns true iff contains value

Returns:

The actual value found, or null, if not

remove

public Object remove(Object value)

Remove a value from the ordered list. At most one value is removed.

Specified by:

remove in interface Structure

Parameters:

value - The value to be removed

Precondition:

value is non-null

Postcondition:

an instance of value is removed, if in list

Returns:

The actual value removed from the list

size

public int size()

Determine the number of elements in the list

Specified by:

size in interface Structure

Precondition:

returns the number of elements in the ordered list

Returns:

The number of elements in the list

isEmpty

public boolean isEmpty()

Determine if the list is empty

Specified by:

isEmpty in interface Structure

Overrides:

isEmpty in class AbstractStructure

Postcondition:

returns true iff the size is non-zero

Returns:

True if the ordered list is empty

iterator

public Iterator iterator()

Construct an iterator for traversing elements of ordered list in ascending order

Specified by:

iterator in interface Structure

Postcondition:

returns an iterator over ordered list

Returns:

An iterator traversing elements in ascending order

toString

public String toString()

Generate string representation of the ordered list

Overrides:

toString in class Object

Postcondition:

returns string representation of list

Returns:

String representing ordered list