Inserts the specified element into the queue represented by this deque (in other words, at the tail of this deque) if it is possible to do so immediately without violating capacity restrictions, returning true upon success and throwing an IllegalStateException if no space is currently available.

  Inserts the specified element into the queue represented by this deque (in other words, at the tail of this deque) if it is possible to do so immediately without violating capacity restrictions, returning true upon success and throwing an IllegalStateException if no space is currently available. When using a capacity-restricted deque, it is generally preferable to use offer.

This method is equivalent to addLast.
Parameters:
- e - the element to add
Throws:
- IllegalStateException - {@inheritDoc}
- ClassCastException - if the class of the specified element prevents it from being added to this deque
- NullPointerException - if the specified element is null
- IllegalArgumentException - if some property of the specified element prevents it from being added to this deque

  Inserts the specified element at the front of this deque if it is possible to do so immediately without violating capacity restrictions, throwing an IllegalStateException if no space is currently available.

  Inserts the specified element at the front of this deque if it is
possible to do so immediately without violating capacity restrictions,
throwing an IllegalStateException if no space is currently
available. When using a capacity-restricted deque, it is generally
preferable to use offerFirst.
Parameters:
- e - the element to add
Throws:
- IllegalStateException - {@inheritDoc}
- ClassCastException - {@inheritDoc}
- NullPointerException - if the specified element is null
- IllegalArgumentException - {@inheritDoc}

  Inserts the specified element at the end of this deque if it is possible to do so immediately without violating capacity restrictions, throwing an IllegalStateException if no space is currently available.

  Inserts the specified element at the end of this deque if it is
possible to do so immediately without violating capacity restrictions,
throwing an IllegalStateException if no space is currently
available. When using a capacity-restricted deque, it is generally
preferable to use offerLast.
Parameters:
- e - the element to add
Throws:
- IllegalStateException - {@inheritDoc}
- ClassCastException - {@inheritDoc}
- NullPointerException - if the specified element is null
- IllegalArgumentException - {@inheritDoc}

  Returns true if this deque contains the specified element.

  Returns true if this deque contains the specified element.
More formally, returns true if and only if this deque contains
at least one element e such that o.equals(e).
Returns: true if this deque contains the specified element
Parameters:
- o - object to be checked for containment in this deque
Throws:
- ClassCastException - if the class of the specified element is incompatible with this deque (optional)
- NullPointerException - if the specified element is null (optional)

  Retrieves, but does not remove, the head of the queue represented by this deque (in other words, the first element of this deque).

  Retrieves, but does not remove, the head of the queue represented by this deque (in other words, the first element of this deque). This method differs from peek only in that it throws an exception if this deque is empty.

This method is equivalent to getFirst.
Returns: the head of this deque
Throws:
- NoSuchElementException - if this deque is empty

  Returns an iterator over the elements in this deque in proper sequence.

  Returns an iterator over the elements in this deque in proper sequence.
The elements will be returned in order from first (head) to last (tail).
Returns: an iterator over the elements in this deque in proper sequence

  Inserts the specified element into the queue represented by this deque (in other words, at the tail of this deque) if it is possible to do so immediately without violating capacity restrictions, returning true upon success and false if no space is currently available.

  Inserts the specified element into the queue represented by this deque (in other words, at the tail of this deque) if it is possible to do so immediately without violating capacity restrictions, returning true upon success and false if no space is currently available. When using a capacity-restricted deque, this method is generally preferable to the BlockingDeque.add(E) method, which can fail to insert an element only by throwing an exception.

This method is equivalent to offerLast.
Parameters:
- e - the element to add
Throws:
- ClassCastException - if the class of the specified element prevents it from being added to this deque
- NullPointerException - if the specified element is null
- IllegalArgumentException - if some property of the specified element prevents it from being added to this deque

  Inserts the specified element into the queue represented by this deque (in other words, at the tail of this deque), waiting up to the specified wait time if necessary for space to become available.

  Inserts the specified element into the queue represented by this deque (in other words, at the tail of this deque), waiting up to the specified wait time if necessary for space to become available.

This method is equivalent to offerLast.
Returns: true if the element was added to this deque, else false
Parameters:
- e - the element to add
Throws:
- InterruptedException - {@inheritDoc}
- ClassCastException - if the class of the specified element prevents it from being added to this deque
- NullPointerException - if the specified element is null
- IllegalArgumentException - if some property of the specified element prevents it from being added to this deque

  Inserts the specified element at the front of this deque if it is possible to do so immediately without violating capacity restrictions, returning true upon success and false if no space is currently available.

  Inserts the specified element at the front of this deque if it is
possible to do so immediately without violating capacity restrictions,
returning true upon success and false if no space is
currently available.
When using a capacity-restricted deque, this method is generally
preferable to the addFirst method, which can
fail to insert an element only by throwing an exception.
Parameters:
- e - the element to add
Throws:
- ClassCastException - {@inheritDoc}
- NullPointerException - if the specified element is null
- IllegalArgumentException - {@inheritDoc}

  Inserts the specified element at the front of this deque, waiting up to the specified wait time if necessary for space to become available.

  Inserts the specified element at the front of this deque,
waiting up to the specified wait time if necessary for space to
become available.
Returns: true if successful, or false if the specified waiting time elapses before space is available
Parameters:
- e - the element to add
- timeout - how long to wait before giving up, in units of unit
- unit - a TimeUnit determining how to interpret the timeout parameter
Throws:
- InterruptedException - if interrupted while waiting
- ClassCastException - if the class of the specified element prevents it from being added to this deque
- NullPointerException - if the specified element is null
- IllegalArgumentException - if some property of the specified element prevents it from being added to this deque

  Inserts the specified element at the end of this deque if it is possible to do so immediately without violating capacity restrictions, returning true upon success and false if no space is currently available.

  Inserts the specified element at the end of this deque if it is
possible to do so immediately without violating capacity restrictions,
returning true upon success and false if no space is
currently available.
When using a capacity-restricted deque, this method is generally
preferable to the addLast method, which can
fail to insert an element only by throwing an exception.
Parameters:
- e - the element to add
Throws:
- ClassCastException - {@inheritDoc}
- NullPointerException - if the specified element is null
- IllegalArgumentException - {@inheritDoc}

  Inserts the specified element at the end of this deque, waiting up to the specified wait time if necessary for space to become available.

  Inserts the specified element at the end of this deque,
waiting up to the specified wait time if necessary for space to
become available.
Returns: true if successful, or false if the specified waiting time elapses before space is available
Parameters:
- e - the element to add
- timeout - how long to wait before giving up, in units of unit
- unit - a TimeUnit determining how to interpret the timeout parameter
Throws:
- InterruptedException - if interrupted while waiting
- ClassCastException - if the class of the specified element prevents it from being added to this deque
- NullPointerException - if the specified element is null
- IllegalArgumentException - if some property of the specified element prevents it from being added to this deque

  Retrieves, but does not remove, the head of the queue represented by this deque (in other words, the first element of this deque), or returns null if this deque is empty.

  Retrieves, but does not remove, the head of the queue represented by this deque (in other words, the first element of this deque), or returns null if this deque is empty.

This method is equivalent to peekFirst.
Returns: the head of this deque, or null if this deque is empty

  Retrieves and removes the head of the queue represented by this deque (in other words, the first element of this deque), or returns null if this deque is empty.

  Retrieves and removes the head of the queue represented by this deque (in other words, the first element of this deque), or returns null if this deque is empty.

This method is equivalent to Deque.pollFirst().
Returns: the head of this deque, or null if this deque is empty

  Retrieves and removes the head of the queue represented by this deque (in other words, the first element of this deque), waiting up to the specified wait time if necessary for an element to become available.

  Retrieves and removes the head of the queue represented by this deque (in other words, the first element of this deque), waiting up to the specified wait time if necessary for an element to become available.

This method is equivalent to pollFirst.
Returns: the head of this deque, or null if the specified waiting time elapses before an element is available
Throws:
- InterruptedException - if interrupted while waiting

  Retrieves and removes the first element of this deque, waiting up to the specified wait time if necessary for an element to become available.

  Retrieves and removes the first element of this deque, waiting
up to the specified wait time if necessary for an element to
become available.
Returns: the head of this deque, or null if the specified waiting time elapses before an element is available
Parameters:
- timeout - how long to wait before giving up, in units of unit
- unit - a TimeUnit determining how to interpret the timeout parameter
Throws:
- InterruptedException - if interrupted while waiting

  Retrieves and removes the last element of this deque, waiting up to the specified wait time if necessary for an element to become available.

  Retrieves and removes the last element of this deque, waiting
up to the specified wait time if necessary for an element to
become available.
Returns: the tail of this deque, or null if the specified waiting time elapses before an element is available
Parameters:
- timeout - how long to wait before giving up, in units of unit
- unit - a TimeUnit determining how to interpret the timeout parameter
Throws:
- InterruptedException - if interrupted while waiting

  Pushes an element onto the stack represented by this deque.

  Pushes an element onto the stack represented by this deque. In other words, inserts the element at the front of this deque unless it would violate capacity restrictions.

This method is equivalent to addFirst.
Throws:
- IllegalStateException - {@inheritDoc}
- ClassCastException - {@inheritDoc}
- NullPointerException - if the specified element is null
- IllegalArgumentException - {@inheritDoc}

  Inserts the specified element into the queue represented by this deque (in other words, at the tail of this deque), waiting if necessary for space to become available.

  Inserts the specified element into the queue represented by this deque (in other words, at the tail of this deque), waiting if necessary for space to become available.

This method is equivalent to putLast.
Parameters:
- e - the element to add
Throws:
- InterruptedException - {@inheritDoc}
- ClassCastException - if the class of the specified element prevents it from being added to this deque
- NullPointerException - if the specified element is null
- IllegalArgumentException - if some property of the specified element prevents it from being added to this deque

  Inserts the specified element at the front of this deque, waiting if necessary for space to become available.

  Inserts the specified element at the front of this deque,
waiting if necessary for space to become available.
Parameters:
- e - the element to add
Throws:
- InterruptedException - if interrupted while waiting
- ClassCastException - if the class of the specified element prevents it from being added to this deque
- NullPointerException - if the specified element is null
- IllegalArgumentException - if some property of the specified element prevents it from being added to this deque

  Inserts the specified element at the end of this deque, waiting if necessary for space to become available.

  Inserts the specified element at the end of this deque,
waiting if necessary for space to become available.
Parameters:
- e - the element to add
Throws:
- InterruptedException - if interrupted while waiting
- ClassCastException - if the class of the specified element prevents it from being added to this deque
- NullPointerException - if the specified element is null
- IllegalArgumentException - if some property of the specified element prevents it from being added to this deque

  Retrieves and removes the head of the queue represented by this deque (in other words, the first element of this deque).

  Retrieves and removes the head of the queue represented by this deque (in other words, the first element of this deque). This method differs from poll only in that it throws an exception if this deque is empty.

This method is equivalent to removeFirst.
Returns: the head of the queue represented by this deque
Throws:
- NoSuchElementException - if this deque is empty

  Removes the first occurrence of the specified element from this deque.

  Removes the first occurrence of the specified element from this deque. If the deque does not contain the element, it is unchanged. More formally, removes the first element e such that o.equals(e) (if such an element exists). Returns true if this deque contained the specified element (or equivalently, if this deque changed as a result of the call).

This method is equivalent to removeFirstOccurrence.
Returns: true if this deque changed as a result of the call
Parameters:
- o - element to be removed from this deque, if present
Throws:
- ClassCastException - if the class of the specified element is incompatible with this deque (optional)
- NullPointerException - if the specified element is null (optional)

  Removes the first occurrence of the specified element from this deque.

  Removes the first occurrence of the specified element from this deque.
If the deque does not contain the element, it is unchanged.
More formally, removes the first element e such that
o.equals(e) (if such an element exists).
Returns true if this deque contained the specified element
(or equivalently, if this deque changed as a result of the call).
Returns: true if an element was removed as a result of this call
Parameters:
- o - element to be removed from this deque, if present
Throws:
- ClassCastException - if the class of the specified element is incompatible with this deque (optional)
- NullPointerException - if the specified element is null (optional)

  Removes the last occurrence of the specified element from this deque.

  Removes the last occurrence of the specified element from this deque.
If the deque does not contain the element, it is unchanged.
More formally, removes the last element e such that
o.equals(e) (if such an element exists).
Returns true if this deque contained the specified element
(or equivalently, if this deque changed as a result of the call).
Returns: true if an element was removed as a result of this call
Parameters:
- o - element to be removed from this deque, if present
Throws:
- ClassCastException - if the class of the specified element is incompatible with this deque (optional)
- NullPointerException - if the specified element is null (optional)

  Returns the number of elements in this deque.

  Returns the number of elements in this deque.
Returns: the number of elements in this deque

  Retrieves and removes the head of the queue represented by this deque (in other words, the first element of this deque), waiting if necessary until an element becomes available.

  Retrieves and removes the head of the queue represented by this deque (in other words, the first element of this deque), waiting if necessary until an element becomes available.

This method is equivalent to takeFirst.
Returns: the head of this deque
Throws:
- InterruptedException - if interrupted while waiting

  Retrieves and removes the first element of this deque, waiting if necessary until an element becomes available.

  Retrieves and removes the first element of this deque, waiting
if necessary until an element becomes available.
Returns: the head of this deque
Throws:
- InterruptedException - if interrupted while waiting

  Retrieves and removes the last element of this deque, waiting if necessary until an element becomes available.

  Retrieves and removes the last element of this deque, waiting
if necessary until an element becomes available.
Returns: the tail of this deque
Throws:
- InterruptedException - if interrupted while waiting