structure
Class AbstractList

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

All Implemented Interfaces:

List, Structure

Direct Known Subclasses:

CircularList, DoublyLinkedList, SinglyLinkedList, Vector

public abstract class AbstractList

extends AbstractStructure

implements List

An abstract structure implementing features common to all list-like structures in this package.

Lists are typically used to store data of unknown or varying length. The structure package provides several extensions of the AbstractList class, each of which has its particular strengths and weaknesses.

Example usage: To place a copy of every unique parameter passed to a program into a List, we could use the following:

 public static void main(String[] arguments)
 {
     AbstractList argList = new SinglyLinkedList();
     for (int i = 0; i < arguments.length; i++){
	   if (!argList.contains(arguments[i])){
	       argList.add(arguments[i]);
         }
    }
    System.out.println(argList);
 }
 

See Also:

DoublyLinkedList, CircularList, SinglyLinkedList

Constructor Summary

AbstractList()
Default constructor for AbstractLists

Method Summary

void	add(Object value) Add an object to tail of list.
void	addFirst(Object value) Add a value to head of list.
void	addLast(Object value) Add a value to tail of list.
boolean	contains(Object value) Check to see if a value is in list.
Object	get() Retrieves value from tail of list.
Object	getFirst() Fetch first element of list.
Object	getLast() Fetch last element of list.
boolean	isEmpty() Determine if list is empty.
Object	remove() Removes value from tail of list.
Object	removeFirst() Remove a value from first element of list.
Object	removeLast() Remove last value from list.

Methods inherited from class structure.AbstractStructure

elements, hashCode, values

Methods inherited from class java.lang.Object

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

Methods inherited from interface structure.List

add, clear, get, indexOf, iterator, lastIndexOf, remove, remove, set, size

Methods inherited from interface structure.Structure

elements, values

Constructor Detail

AbstractList

public AbstractList()

Default constructor for AbstractLists

Method Detail

isEmpty

public boolean isEmpty()

Determine if list is empty.

Specified by:

isEmpty in interface List

Overrides:

isEmpty in class AbstractStructure

Postcondition:

returns true iff list has no elements

Returns:

True if list has no elements.

addFirst

public void addFirst(Object value)

Add a value to head of list.

Specified by:

addFirst in interface List

Parameters:

value - The value to be added to head of list.

Postcondition:

value is added to beginning of list

addLast

public void addLast(Object value)

Add a value to tail of list.

Specified by:

addLast in interface List

Parameters:

value - The value to be added to tail of list.

Postcondition:

value is added to end of list

getFirst

public Object getFirst()

Fetch first element of list.

Specified by:

getFirst in interface List

Precondition:

list is not empty

Postcondition:

returns first value in list

Returns:

A reference to first element of list.

getLast

public Object getLast()

Fetch last element of list.

Specified by:

getLast in interface List

Precondition:

list is not empty

Postcondition:

returns last value in list

Returns:

A reference to last element of list.

removeFirst

public Object removeFirst()

Remove a value from first element of list.

Specified by:

removeFirst in interface List

Precondition:

list is not empty

Postcondition:

removes first value from list

Returns:

value actually removed.

removeLast

public Object removeLast()

Remove last value from list.

Specified by:

removeLast in interface List

Precondition:

list is not empty

Postcondition:

removes last value from list

Returns:

value actually removed.

add

public void add(Object value)

Add an object to tail of list.

Specified by:

add in interface List

Parameters:

value - The value to be added to tail of list.

Postcondition:

value is added to tail of list

See Also:

addLast(java.lang.Object)

remove

public Object remove()

Removes value from tail of list.

Specified by:

remove in interface List

Precondition:

list has at least one element

Postcondition:

removes last value found in list

Returns:

object removed.

get

public Object get()

Retrieves value from tail of list.

Specified by:

get in interface List

Precondition:

list has at least one element

Postcondition:

returns last value found in list

Returns:

object found at end of list

contains

public boolean contains(Object value)

Check to see if a value is in list.

Specified by:

contains in interface List

Overrides:

contains in class AbstractStructure

Parameters:

value - value sought.

Precondition:

value is not null

Postcondition:

returns true iff list contains an object equal to value

Returns:

True if value is within list.