craterdog.collections.abstractions

Class Iterator<E>

java.lang.Object

craterdog.collections.abstractions.Iterator<E>

Type Parameters:

E - The type of the element being iterated over.

All Implemented Interfaces:

java.util.Iterator<E>

Direct Known Subclasses:

Manipulator

public abstract class Iterator<E>
extends java.lang.Object
implements java.util.Iterator<E>

This abstract class defines a framework for each concrete iterator class that allows the iteration over a collection's elements. The iterator points at the slots on either side of the elements in the collection:

            [element 1]   [element 2]   [element 3]  ...  [element N]
          ^             ^             ^             ^   ^             ^
       at start                                                    at end
 

Author:

Derk Norton

Constructor Summary

Constructors

Constructor and Description
Iterator()

Method Summary

Modifier and Type	Method and Description
abstract E	getNextElement() This method returns the element after the slot where the iterator is currently pointing.
abstract E	getPreviousElement() This method returns the element before the slot where the iterator is currently pointing.
abstract void	goToEnd() This method moves the iterator to the slot just past the last element in this collection.
abstract void	goToIndex(int index) This method moves the iterator to the slot just before the specified index.
abstract void	goToStart() This method moves the iterator to just before the first element in this collection.
boolean	hasNext()
abstract boolean	hasNextElement() This method determines if the iterator is currently pointing at a slot just before an element in this collection.
abstract boolean	hasPreviousElement() This method determines if the iterator is currently pointing at a slot just after an element in this collection.
E	next()
void	remove()

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.util.Iterator

forEachRemaining

Constructor Detail

Iterator

public Iterator()

Method Detail

goToStart

public abstract void goToStart()

This method moves the iterator to just before the first element in this collection. The next element to be returned will the first element in this collection.

goToIndex

public abstract void goToIndex(int index)

This method moves the iterator to the slot just before the specified index. The next element to be returned will then be the element with that index.

Parameters:

index - This index of element to be returned next by the iterator.

goToEnd

public abstract void goToEnd()

This method moves the iterator to the slot just past the last element in this collection. There is no next element that can be returned from this position.

hasPreviousElement

public abstract boolean hasPreviousElement()

This method determines if the iterator is currently pointing at a slot just after an element in this collection. If the iterator is at the start of the collection this method will return false.

Returns:

Whether or not there is an element just before the current position of the iterator.

hasNextElement

public abstract boolean hasNextElement()

This method determines if the iterator is currently pointing at a slot just before an element in this collection. If the iterator is at the end of the collection this method will return false.

Returns:

Whether or not there is an element just after the current position of the iterator.

getNextElement

public abstract E getNextElement()

This method returns the element after the slot where the iterator is currently pointing. If the iterator is at the end of this collection an exception is thrown.

Returns:

The next element in this collection.

getPreviousElement

public abstract E getPreviousElement()

This method returns the element before the slot where the iterator is currently pointing. If the iterator is at the start of this collection an exception is thrown.

Returns:

The previous element in this collection.

hasNext

public final boolean hasNext()

Specified by:

hasNext in interface java.util.Iterator<E>

next

public final E next()

Specified by:

next in interface java.util.Iterator<E>

remove

public final void remove()

Specified by:

remove in interface java.util.Iterator<E>