PropWare::Queue< T > Class Template Reference

A basic first-in, first-out queue implementation. The queue will overwrite itself when the maximum size is reached. More...

#include <PropWare/utility/collection/queue.h>

Public Member Functions
template<size_t N>
	Queue (T(&array)[N], const int lockNumber=locknew())
	Construct a queue using the given statically-allocated array. More...
	Queue (T *array, const size_t length, const int lockNumber)
	Construct a queue using the given dynamically allocated array (i.e., with new or malloc) More...
size_t	size () const
	Obtain the number of elements in the queue. More...
bool	is_empty () const
	Determine if any elements exist. More...
bool	is_full () const
	Determine if inserting another element would overwrite data. More...
void	clear ()
	Remove all data from the queue.
virtual Queue &	enqueue (const T &value)
	Insert an element to the buffer. More...
Queue &	insert (const T &value)
virtual T	dequeue ()
	Return and remove the oldest value in the buffer. More...
T	peek () const
	Return the oldest value in the buffer without removing it from the buffer. More...
bool	check (const T &value) const
	Determine if a value is valid. More...

Detailed Description

template<typename T>
class PropWare::Queue< T >

A basic first-in, first-out queue implementation. The queue will overwrite itself when the maximum size is reached.

Examples

I2CSlave_Demo.cpp, and Queue_Demo.cpp.

Definition at line 44 of file queue.h.

Constructor & Destructor Documentation

Queue() [1/2]

template<typename T >

template<size_t N>

PropWare::Queue< T >::Queue	(	T(&)	array[N],
		const int	lockNumber = locknew()
	)

Construct a queue using the given statically-allocated array.

Parameters

[in]

array

Statically allocated instance of an array, NOT a pointer

Definition at line 52 of file queue.h.

Queue() [2/2]

template<typename T >

PropWare::Queue< T >::Queue	(	T *	array,
		const size_t	length,
		const int	lockNumber
	)

Construct a queue using the given dynamically allocated array (i.e., with new or malloc)

This constructor is not recommended unless dynamic allocation is used. When using statically allocated arrays, use the single-parameter constructor

Parameters

[in]	array	Address where the array begins
[in]	length	Number of elements allocated for the array

Definition at line 71 of file queue.h.

Member Function Documentation

check()

template<typename T >

bool PropWare::Queue< T >::check

(

const T &

value

)

const

Determine if a value is valid.

If the queue is read (deque or peek) when the size is 0 then a value at address 0 is returned. A better implementation would throw an exception when this occurs, but that isn't feasible on the Propeller. Use this method if you want to ensure values are valid prior to using them

Parameters

[in]

value

A value returned by PropWare::Queue::peek() or PropWare::Queue::dequeue()

Returns

Whether or not the value is valid

Definition at line 234 of file queue.h.

dequeue()

template<typename T >

virtual T PropWare::Queue< T >::dequeue ( )

virtual

Return and remove the oldest value in the buffer.

Precondition

Buffer must not be empty - no checks are performed to ensure the buffer contains data

Returns

Oldest value in the buffer

Definition at line 181 of file queue.h.

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enqueue()

template<typename T >

virtual Queue& PropWare::Queue< T >::enqueue ( const T &  value )

virtual

Insert an element to the buffer.

Parameters

[in]

value

Value to be inserted at the end of the buffer

Postcondition

If the buffer is already full, the oldest value will be overwritten with the value parameter

Returns

In order to allow chained calls to PropWare::Queue::enqueue, the Queue instance is returned

Definition at line 129 of file queue.h.

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insert()

template<typename T >

Queue& PropWare::Queue< T >::insert

(

const T &

value

)

See also

PropWare::CircularQueue::enqueue(const T &value)

Definition at line 170 of file queue.h.

is_empty()

template<typename T >

bool PropWare::Queue< T >::is_empty

(

)

const

Determine if any elements exist.

Returns

True if there is one or more elements, false otherwise

Definition at line 100 of file queue.h.

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is_full()

template<typename T >

bool PropWare::Queue< T >::is_full

(

)

const

Determine if inserting another element would overwrite data.

Returns

True if the queue can not fit any more data without loosing old data, false otherwise

Definition at line 109 of file queue.h.

peek()

template<typename T >

T PropWare::Queue< T >::peek

(

)

const

Return the oldest value in the buffer without removing it from the buffer.

Precondition

Buffer must not be empty - no checks are performed to ensure the buffer contains data

Returns

Oldest value in the buffer

Definition at line 219 of file queue.h.

size()

template<typename T >

size_t PropWare::Queue< T >::size

(

)

const

Obtain the number of elements in the queue.

Returns

Number of elements in the queue

Definition at line 91 of file queue.h.

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The documentation for this class was generated from the following file:

• PropWare/utility/collection/queue.h