structure5
Class QueueList<E>

java.lang.Object
  structure5.AbstractStructure<E>
      structure5.AbstractLinear<E>
          structure5.AbstractQueue<E>
              structure5.QueueList<E>

All Implemented Interfaces:

java.lang.Iterable<E>, Linear<E>, Queue<E>, Structure<E>

public class QueueList<E>
extends AbstractQueue<E>
implements Queue<E>

An implementation of queues based on circular lists. The head of the queue is stored at the head of the list, allowing the queue to grow and shrink in constant time. This queue implementation is ideal for applications that require a dynamically resizable queue that resizes in constant time.

Example usage:

To compute the sum of the unicode value of every character in the standard input we could use the following:

 public static void main(String[] arguments)
 {
     QueueList q = new QueueList();
     int unicodeSum = 0;

     if(arguments.length > 0){
         for(int i=0; i < arguments.length; i++){
             for(int j=0; j < arguments[i].length(); j++){
                 q.enqueue(new Character(arguments[i].charAt(j)));
             }
         }
     }

     while(!q.AbstractLinear.empty()){
        char c = ((Character)q.AbstractQueue.dequeue()).charValue();
        unicodeSum+=Character.getNumericValue(c);
     }

     System.out.println("Total Value: " + unicodeSum);
 }
 

See Also:

QueueArray, QueueVector

Field Summary

protected List<E>

data The list holding queue values in order.

Constructor Summary

QueueList()
Construct a new queue with no data.

Method Summary

void	add(E value) Add a value to the tail of the queue.
void	clear() Remove all the values from the queue.
E	get() Fetch the value at the head of the queue.
boolean	isEmpty() Determine if the queue is empty.
java.util.Iterator<E>	iterator() Returns an iterator for traversing the structure.
E	remove() Remove a value from the head of the queue.
int	size() Determine the number of elements within the queue.
java.lang.String	toString() Construct a string representation of the queue.

Methods inherited from class structure5.AbstractQueue

dequeue, enqueue, getFirst, peek

Methods inherited from class structure5.AbstractLinear

empty, remove

Methods inherited from class structure5.AbstractStructure

contains, elements, hashCode, values

Methods inherited from class java.lang.Object

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

Methods inherited from interface structure5.Queue

dequeue, empty, enqueue, getFirst, peek

Methods inherited from interface structure5.Structure

contains, elements, remove, values

Field Detail

data

protected List<E> data

The list holding queue values in order.

Constructor Detail

QueueList

public QueueList()

Construct a new queue with no data.

Postcondition:

Constructs a new, empty queue

Method Detail

add

public void add(E value)

Add a value to the tail of the queue.

Specified by:

add in interface Linear<E>

Specified by:

add in interface Queue<E>

Specified by:

add in interface Structure<E>

Parameters:

value - The value added.

See Also:

AbstractQueue.enqueue(E)

Postcondition:

The value is added to the tail of the structure

remove

public E remove()

Remove a value from the head of the queue.

Specified by:

remove in interface Linear<E>

Specified by:

remove in interface Queue<E>

Returns:

The value actually removed.

See Also:

AbstractQueue.dequeue()

Precondition:

The queue is not empty

Postcondition:

The head of the queue is removed and returned

get

public E get()

Fetch the value at the head of the queue.

Specified by:

get in interface Linear<E>

Specified by:

get in interface Queue<E>

Returns:

Reference to the first value of the queue.

Precondition:

The queue is not empty

Postcondition:

The element at the head of the queue is returned

size

public int size()

Determine the number of elements within the queue.

Specified by:

size in interface Linear<E>

Specified by:

size in interface Queue<E>

Specified by:

size in interface Structure<E>

Returns:

The number of elements within the queue.

Postcondition:

Returns the number of elements in the queue

clear

public void clear()

Remove all the values from the queue.

Specified by:

clear in interface Structure<E>

Postcondition:

Removes all elements from the queue

isEmpty

public boolean isEmpty()

Determine if the queue is empty.

Specified by:

isEmpty in interface Structure<E>

Overrides:

isEmpty in class AbstractStructure<E>

Returns:

True iff the queue is empty.

Postcondition:

Returns true iff the queue is empty

iterator

public java.util.Iterator<E> iterator()

Description copied from interface: Structure

Returns an iterator for traversing the structure.

Specified by:

iterator in interface java.lang.Iterable<E>

Specified by:

iterator in interface Structure<E>

Returns:

an iterator for traversing the structure

See Also:

AbstractIterator, Iterator, Enumeration, Structure.elements()

toString

public java.lang.String toString()

Construct a string representation of the queue.

Overrides:

toString in class java.lang.Object

Returns:

String representing the queue.

Postcondition:

Returns string representation of queue