com.opencloud.sentinel.multileg

Interface MessageQueue<T>

Type Parameters:

T -

All Superinterfaces:

java.lang.Iterable<T>

All Known Subinterfaces:

SipMessageQueue

public interface MessageQueue<T>
extends java.lang.Iterable<T>

Interface for message queue.

Method Summary

Methods

Modifier and Type	Method and Description
boolean	add(T e) Adds an element to the end of the queue.
void	addFirst(T e) Add an element to the start of the queue.
void	clear() Removes all of the elements from this queue.
T	element() Retrieves, but does not remove, the head of this queue.
boolean	isEmpty() Determines if queue is empty.
boolean	offer(T e) Inserts the specified element into this queue if it is possible to do so immediately without violating capacity restrictions.
T	peek() Retrieves , but does not remove, the head of this queue, or returns null if this queue is empty.
T	peekLast() Retrieves , but does not remove, the last element of this queue, or returns null if this queue is empty.
T	poll() Retrieves and removes the head of this queue, or returns null if this queue is empty.
T	remove() Retrieves and removes the head of this queue.
int	size() Returns the number of elements in this collection.

Methods inherited from interface java.lang.Iterable

iterator

Method Detail

add

boolean add(T e)

Adds an element to the end of the queue.

Parameters:

e - the element to add, not null.

Throws:

java.lang.NullPointerException - if the specified element is null

offer

boolean offer(T e)

Inserts the specified element into this queue if it is possible to do so immediately without violating capacity restrictions. When using a capacity-restricted queue, this method is generally preferable to add(T), which can fail to insert an element only by throwing an exception.

Parameters:

e - the element to add

Returns:

true if the element was added to this queue, else false

Throws:

java.lang.ClassCastException - if the class of the specified element prevents it from being added to this queue

java.lang.NullPointerException - if the specified element is null and this queue does not permit null elements

java.lang.IllegalArgumentException - if some property of this element prevents it from being added to this queue

peek

T peek()

Retrieves , but does not remove, the head of this queue, or returns null if this queue is empty.

Returns:

head of queue, or null if empty queue.

addFirst

void addFirst(T e)

Add an element to the start of the queue.

Parameters:

e - the message to add, not null.

Throws:

java.lang.NullPointerException - if the specified element is null

peekLast

T peekLast()

Retrieves , but does not remove, the last element of this queue, or returns null if this queue is empty.

Returns:

last element of queue, or null if empty queue.

clear

void clear()

Removes all of the elements from this queue.

isEmpty

boolean isEmpty()

Determines if queue is empty.

Returns:

true if queue is empty.

remove

T remove()

Retrieves and removes the head of this queue. This method differs from poll only in that it throws an exception if this queue is empty.

Returns:

the head of this queue

Throws:

java.util.NoSuchElementException - if this queue is empty

poll

T poll()

Retrieves and removes the head of this queue, or returns null if this queue is empty.

Returns:

the head of this queue, or null if this queue is empty

element

T element()

Retrieves, but does not remove, the head of this queue. This method differs from peek only in that it throws an exception if this queue is empty.

Returns:

the head of this queue

Throws:

java.util.NoSuchElementException - if this queue is empty

size

int size()

Returns the number of elements in this collection. If this collection contains more than Integer.MAX_VALUE elements, returns Integer.MAX_VALUE.

Returns:

the number of elements in this collection