structure
Interface List

All Superinterfaces:

Structure

All Known Implementing Classes:

AbstractList, CircularList, DoublyLinkedList, SinglyLinkedList, Vector

public interface List
extends Structure

Interface describing lists. Lists are collections of data with a head and tail. Values may be added or removed from either end, as well as by value from the middle.

See Also:

SinglyLinkedList, DoublyLinkedList, CircularList

Method Summary

void	add(int i, java.lang.Object o) Insert value at location.
void	add(java.lang.Object value) Add an object to tail of list.
void	addFirst(java.lang.Object value) Add a value to the head of the list.
void	addLast(java.lang.Object value) Add a value to tail of list.
void	clear() Remove all elements of list.
boolean	contains(java.lang.Object value) Check to see if a value is in list.
java.lang.Object	get() Retrieves value from tail of list.
java.lang.Object	get(int i) Get value at location i.
java.lang.Object	getFirst() Fetch first element of list.
java.lang.Object	getLast() Fetch last element of list.
int	indexOf(java.lang.Object value) Determine first location of a value in list.
boolean	isEmpty() Determine if list is empty.
java.util.Iterator	iterator() Construct an iterator to traverse elements of list from head to tail, in order.
int	lastIndexOf(java.lang.Object value) Determine last location of a value in list.
java.lang.Object	remove() Removes value from tail of list.
java.lang.Object	remove(int i) Remove and return value at location i.
java.lang.Object	remove(java.lang.Object value) Remove a value from list.
java.lang.Object	removeFirst() Remove a value from first element of list.
java.lang.Object	removeLast() Remove last value from list.
java.lang.Object	set(int i, java.lang.Object o) Set value stored at location i to object o, returning old value.
int	size() Determine size of list.

Methods inherited from interface structure.Structure

elements, values

Method Detail

size

int size()

Determine size of list.

Specified by:

size in interface Structure

Returns:

The number of elements in list.

Postcondition:

returns number of elements in list

isEmpty

boolean isEmpty()

Determine if list is empty.

Specified by:

isEmpty in interface Structure

Returns:

True if list has no elements.

Postcondition:

returns true iff list has no elements

clear

void clear()

Remove all elements of list.

Specified by:

clear in interface Structure

Postcondition:

empties list

addFirst

void addFirst(java.lang.Object value)

Add a value to the head of the list.

Parameters:

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

Postcondition:

value is added to beginning of list

addLast

void addLast(java.lang.Object value)

Add a value to tail of list.

Parameters:

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

Postcondition:

value is added to end of list

getFirst

java.lang.Object getFirst()

Fetch first element of list.

Returns:

A reference to first element of list.

Precondition:

list is not empty

Postcondition:

returns first value in list

getLast

java.lang.Object getLast()

Fetch last element of list.

Returns:

A reference to last element of list.

Precondition:

list is not empty

Postcondition:

returns last value in list

removeFirst

java.lang.Object removeFirst()

Remove a value from first element of list.

Returns:

The value actually removed.

Precondition:

list is not empty

Postcondition:

removes first value from list

removeLast

java.lang.Object removeLast()

Remove last value from list.

Returns:

The value actually removed.

Precondition:

list is not empty

Postcondition:

removes last value from list

remove

java.lang.Object remove(java.lang.Object value)

Remove a value from list. At most one of value will be removed.

Specified by:

remove in interface Structure

Parameters:

value - The value to be removed.

Returns:

The actual value removed.

Postcondition:

removes and returns element equal to value otherwise returns null

add

void add(java.lang.Object value)

Add an object to tail of list.

Specified by:

add in interface Structure

Parameters:

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

See Also:

addLast(java.lang.Object)

Postcondition:

value is added to tail of list

remove

java.lang.Object remove()

Removes value from tail of list.

Returns:

object removed.

Precondition:

list has at least one element

Postcondition:

removes last value found in list

get

java.lang.Object get()

Retrieves value from tail of list.

Returns:

object found at end of list

Precondition:

list has at least one element

Postcondition:

returns last value found in list

contains

boolean contains(java.lang.Object value)

Check to see if a value is in list.

Specified by:

contains in interface Structure

Parameters:

value - value sought.

Returns:

True if value is within list.

Precondition:

value is not null

Postcondition:

returns true iff list contains an object equal to value

indexOf

int indexOf(java.lang.Object value)

Determine first location of a value in list.

Parameters:

value - The value sought.

Returns:

index (0 is first element) of value, or -1

Precondition:

value is not null

Postcondition:

returns (0-origin) index of value, or -1 if value is not found

lastIndexOf

int lastIndexOf(java.lang.Object value)

Determine last location of a value in list.

Parameters:

value - value sought.

Returns:

index (0 is first element) of value, or -1

Precondition:

value is not null

Postcondition:

returns (0-origin) index of value, or -1 if value is not found

get

java.lang.Object get(int i)

Get value at location i.

Parameters:

i - position of value to be retrieved.

Returns:

value retrieved from location i (returns null if i invalid)

Precondition:

0 <= i < size()

Postcondition:

returns object found at that location

set

java.lang.Object set(int i,
                     java.lang.Object o)

Set value stored at location i to object o, returning old value.

Parameters:

i - location of entry to be changed.

o - new value

Returns:

former value of ith entry of list.

Precondition:

0 <= i < size()

Postcondition:

sets ith entry of list to value o; returns old value

add

void add(int i,
         java.lang.Object o)

Insert value at location.

Parameters:

i - index of this new value

o - value to be stored

Precondition:

0 <= i <= size()

Postcondition:

adds ith entry of list to value o

remove

java.lang.Object remove(int i)

Remove and return value at location i.

Parameters:

i - position of value to be retrieved.

Returns:

value retrieved from location i (returns null if i invalid)

Precondition:

0 <= i < size()

Postcondition:

removes and returns object found at that location

iterator

java.util.Iterator iterator()

Construct an iterator to traverse elements of list from head to tail, in order.

Specified by:

iterator in interface Structure

Returns:

Iterator that traverses list.

See Also:

AbstractIterator, Iterator, Enumeration, Structure.elements()

Postcondition:

returns an iterator allowing ordered traversal of elements in list