This class provides skeletal implementations of some Queue operations. More...

#include <src/main/decaf/util/AbstractQueue.h>

Inheritance diagram for decaf::util::AbstractQueue< E >:

Public Member Functions

AbstractQueue ()

virtual ~AbstractQueue ()

virtual bool add (const E &value)

Returns true if this collection changed as a result of the call.(Returns false if this collection does not permit duplicates and already contains the specified element.)Collections that support this operation may place limitations on what elements may be added to this collection. In particular, some collections will refuse to add null elements, and others will impose restrictions on the type of elements that may be added. Collection classes should clearly specify in their documentation any restrictions on what elements may be added.If a collection refuses to add a particular element for any reason other than that it already contains the element, it must throw an exception (rather than returning false). This preserves the invariant that a collection always contains the specified element after this call returns.For non-pointer values, i.e. class instances or string's the object will be copied into the collection, thus the object must support being copied, must not hide the copy constructor and assignment operator.

Parameters

value The reference to the element to add to this Collection.

Returns: true if the element was added to this Collection.

Exceptions

UnsupportedOperationExceptio	if this is an unmodifiable collection.
NullPointerException	if the Collection is a container of pointers and does not allow NULL values.
IllegalArgumentException	if some property of the element prevents it from being added to this collection
IllegalStateException	if the element cannot be added at this time due to insertion restrictions.

More...

virtual bool addAll (const Collection< E > &collection)

Adds all of the elements in the specified collection to this collection.The behavior of this operation is undefined if the specified collection is modified while the operation is in progress. (This implies that the behavior of this call is undefined if the specified collection is this collection, and this collection is nonempty.)

Parameters

collection The Collection whose elements are added to this one.

Returns: true if this collection changed as a result of the call

Exceptions

UnsupportedOperationExceptio	if this is an unmodifiable collection.
NullPointerException	if the Collection is a container of pointers and does not allow NULL values.
IllegalArgumentException	if some property of an element prevents it from being added to this collection
IllegalStateException	if an element cannot be added at this time due to insertion restrictions.

This implementation iterates over the specified collection, and adds each object returned by the iterator to this collection, in turn.Note that this implementation will throw an UnsupportedOperationException unless add is overridden (assuming the specified collection is non-empty). More...

virtual E remove ()

Gets and removes the element in the head of the queue.Throws a NoSuchElementException if there is no element in the queue.

Returns: the element in the head of the queue.

Exceptions

NoSuchElementException if there is no element in the queue.

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virtual E element () const

Gets but not removes the element in the head of the queue.Throws a NoSuchElementException if there is no element in the queue.

Returns: the element in the head of the queue.

Exceptions

NoSuchElementException if there is no element in the queue.

More...

virtual void clear ()

Removes all of the elements from this collection (optional operation).The collection will be empty after this method returns.This implementation iterates over this collection, removing each element using the Iterator.remove operation. Most implementations will probably choose to override this method for efficiency.Note that this implementation will throw an UnsupportedOperationException if the iterator returned by this collection's iterator method does not implement the remove method and this collection is non-empty.

Exceptions

UnsupportedOperationException if the clear operation is not supported by this collection

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Public Member Functions inherited from decaf::util::Queue< E >

virtual ~Queue ()

virtual bool offer (const E &value)=0

Inserts the specified element into the queue provided that the condition allows such an operation. More...

virtual bool poll (E &result)=0

Gets and removes the element in the head of the queue. More...

virtual bool peek (E &result) const =0

Gets but not removes the element in the head of the queue. More...

Public Member Functions inherited from decaf::util::Collection< E >

virtual ~Collection ()

virtual int size () const =0

Returns the number of elements in this collection. More...

Public Member Functions inherited from decaf::lang::Iterable< E >

virtual ~Iterable ()

virtual decaf::util::Iterator
< E > * iterator ()=0

virtual decaf::util::Iterator
< E > * iterator () const =0

Public Member Functions inherited from decaf::util::concurrent::Synchronizable

virtual ~Synchronizable ()

Public Member Functions inherited from decaf::util::AbstractCollection< E >

AbstractCollection ()

AbstractCollection (const AbstractCollection &other)

Copy Constructor, copy element from the source collection to this collection after clearing any element stored in this collection. More...

virtual ~AbstractCollection ()

AbstractCollection< E > & operator= (const AbstractCollection< E > &collection)

Assignment Operator, copy element from the source collection to this collection after clearing any element stored in this collection. More...

virtual bool contains (const E &value) const

Returns true if this collection contains the specified element.More formally, returns true if and only if this collection contains at least one element e such that (value == NULL ? e == NULL : value == e ).

Parameters

value The value to check for presence in the collection.

Returns: true if there is at least one of the elements in the collection

Exceptions

NullPointerException if the Collection contains pointers and the Collection does not allow for NULL elements (optional check).

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virtual bool containsAll (const Collection< E > &collection) const

Returns true if this collection contains all of the elements in the specified collection.

Parameters

collection The Collection to compare to this one.

Exceptions

NullPointerException if the Collection contains pointers and the Collection does not allow for NULL elements (optional check).

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virtual bool equals (const Collection< E > &collection) const

Answers true if this Collection and the one given are the same size and if each element contained in the Collection given is equal to an element contained in this collection. More...

virtual void copy (const Collection< E > &collection)

Renders this Collection as a Copy of the given Collection. More...

virtual bool isEmpty () const

Returns true if this collection contains no elements. More...

virtual bool add (const E &value DECAF_UNUSED)

virtual bool remove (const E &value)

Removes a single instance of the specified element from the collection.More formally, removes an element e such that (value == NULL ? e == NULL : value == e), if this collection contains one or more such elements. Returns true if this collection contained the specified element (or equivalently, if this collection changed as a result of the call).

Parameters

value The reference to the element to remove from this Collection.

Returns: true if the collection was changed, false otherwise.

Exceptions

UnsupportedOperationExceptio	if this is an unmodifiable collection.
NullPointerException	if the Collection is a container of pointers and does not allow NULL values.

More...

virtual bool removeAll (const Collection< E > &collection)

Removes all this collection's elements that are also contained in the specified collection (optional operation).After this call returns, this collection will contain no elements in common with the specified collection.

Parameters

collection The Collection whose elements are to be removed from this one.

Returns: true if the collection changed as a result of this call.

Exceptions

UnsupportedOperationExceptio	if this is an unmodifiable collection.
NullPointerException	if the Collection is a container of pointers and does not allow NULL values.

More...

virtual bool retainAll (const Collection< E > &collection)

Retains only the elements in this collection that are contained in the specified collection (optional operation).In other words, removes from this collection all of its elements that are not contained in the specified collection.

Parameters

collection The Collection whose elements are to be retained.

Returns: true if the collection changed as a result of this call.

Exceptions

UnsupportedOperationExceptio	if this is an unmodifiable collection.
NullPointerException	if the Collection is a container of pointers and does not allow NULL values.

More...

virtual std::vector< E > toArray () const

Answers an STL vector containing copies of all elements contained in this Collection. More...

virtual void lock ()

Locks the object. More...

virtual bool tryLock ()

Attempts to Lock the object, if the lock is already held by another thread than this method returns false. More...

virtual void unlock ()

Unlocks the object. More...

virtual void wait ()

Waits on a signal from this object, which is generated by a call to Notify. More...

virtual void wait (long long millisecs)

Waits on a signal from this object, which is generated by a call to Notify. More...

virtual void wait (long long millisecs, int nanos)

Waits on a signal from this object, which is generated by a call to Notify. More...

virtual void notify ()

Signals a waiter on this object that it can now wake up and continue. More...

virtual void notifyAll ()

Signals the waiters on this object that it can now wake up and continue. More...

Additional Inherited Members
Protected Attributes inherited from decaf::util::AbstractCollection< E >
util::concurrent::Mutex	mutex

Detailed Description

template<typename E>
class decaf::util::AbstractQueue< E >

This class provides skeletal implementations of some Queue operations.

Methods add, remove, and element are based on offer, poll, and peek, respectively.

A Queue implementation that extends this class must minimally define a method Queue. offer(E) which does not permit insertion of null elements, along with methods Queue. peek(), Queue.poll(), Collection.size(), and a Collection.iterator() supporting Iterator.remove(). Typically, additional methods will be overridden as well. If these requirements cannot be met, consider instead subclassing AbstractCollection.

Since: 1.0

Constructor & Destructor Documentation

template<typename E>

decaf::util::AbstractQueue< E >::AbstractQueue ( )

inline

template<typename E>

virtual decaf::util::AbstractQueue< E >::~AbstractQueue ( )

inlinevirtual

Member Function Documentation

template<typename E>

virtual bool decaf::util::AbstractQueue< E >::add ( const E & value )

inlinevirtual

Returns true if this collection changed as a result of the call.(Returns false if this collection does not permit duplicates and already contains the specified element.)Collections that support this operation may place limitations on what elements may be added to this collection. In particular, some collections will refuse to add null elements, and others will impose restrictions on the type of elements that may be added. Collection classes should clearly specify in their documentation any restrictions on what elements may be added.If a collection refuses to add a particular element for any reason other than that it already contains the element, it must throw an exception (rather than returning false). This preserves the invariant that a collection always contains the specified element after this call returns.For non-pointer values, i.e. class instances or string's the object will be copied into the collection, thus the object must support being copied, must not hide the copy constructor and assignment operator.

Parameters

value The reference to the element to add to this Collection.

Returns: true if the element was added to this Collection.

Exceptions

UnsupportedOperationExceptio	if this is an unmodifiable collection.
NullPointerException	if the Collection is a container of pointers and does not allow NULL values.
IllegalArgumentException	if some property of the element prevents it from being added to this collection
IllegalStateException	if the element cannot be added at this time due to insertion restrictions.

This implementation returns true if offer succeeds, else throws an IllegalStateException.

Implements decaf::util::Collection< E >.

Reimplemented in decaf::util::PriorityQueue< E >.

template<typename E>

virtual bool decaf::util::AbstractQueue< E >::addAll ( const Collection< E > & collection )

inlinevirtual

Adds all of the elements in the specified collection to this collection.The behavior of this operation is undefined if the specified collection is modified while the operation is in progress. (This implies that the behavior of this call is undefined if the specified collection is this collection, and this collection is nonempty.)

Parameters

collection The Collection whose elements are added to this one.

Returns: true if this collection changed as a result of the call

Exceptions

UnsupportedOperationExceptio	if this is an unmodifiable collection.
NullPointerException	if the Collection is a container of pointers and does not allow NULL values.
IllegalArgumentException	if some property of an element prevents it from being added to this collection
IllegalStateException	if an element cannot be added at this time due to insertion restrictions.

This implementation iterates over the specified collection, and adds each object returned by the iterator to this collection, in turn.Note that this implementation will throw an UnsupportedOperationException unless add is overridden (assuming the specified collection is non-empty).

This implementation checks to see if the Queue is being added to itself and throws an IllegalArgumentException if so, otherwise it delegates the add to the AbstractCollection's addAll implementation.

Reimplemented from decaf::util::AbstractCollection< E >.

Referenced by decaf::util::concurrent::LinkedBlockingQueue< decaf::lang::Pointer< activemq::transport::Transport > >::operator=().

template<typename E>

virtual void decaf::util::AbstractQueue< E >::clear ( )

inlinevirtual

Removes all of the elements from this collection (optional operation).The collection will be empty after this method returns.This implementation iterates over this collection, removing each element using the Iterator.remove operation. Most implementations will probably choose to override this method for efficiency.Note that this implementation will throw an UnsupportedOperationException if the iterator returned by this collection's iterator method does not implement the remove method and this collection is non-empty.

Exceptions

UnsupportedOperationException if the clear operation is not supported by this collection

This implementation repeatedly invokes poll until it returns false.

Reimplemented from decaf::util::AbstractCollection< E >.

Reimplemented in decaf::util::concurrent::LinkedBlockingQueue< E >, decaf::util::concurrent::LinkedBlockingQueue< decaf::lang::Pointer< activemq::transport::Transport > >, decaf::util::PriorityQueue< E >, and decaf::util::concurrent::SynchronousQueue< E >.

template<typename E>

virtual E decaf::util::AbstractQueue< E >::element ( ) const

inlinevirtual

Gets but not removes the element in the head of the queue.Throws a NoSuchElementException if there is no element in the queue.