Data Structures and Algorithms in Java[1].pdf - Fulvio Frisone

Deque Method
Realization with Node-List Methods
size(), isEmpty()
size(), isEmpty()
getFirst()
first()·element()
getLast()
last()·element()
addFirst(e)
addFirst(e)
addLast(e)
addLast(e)
removeFirst()
remove(first())
removeLast()
remove(last())
6.2.4 Doubly Linked List Implementation
Suppose we would like to implement the node list ADT using a doubly linked list
(Section 3.3). We can simply make the nodes of the linked list implement the
position ADT. That is, we have each node implement the Position interface and
therefore define a method, element(), which returns the element stored at the
node. Thus, the nodes themselves act as positions. They are viewed internally by
the linked list as nodes, but from the outside, they are viewed only as positions. In
the internal view, we can give each node v instance variables prev and next that
respectively refer to the predecessor and successor nodes of v (which could in fact
be header or trailer sentinel nodes marking the beginning and end of the list).
Instead of using variables prev and next directly, we define methods getPrev,
setPrev, getNext, and setNext of a node to access and modify these
variables.
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