DoublyLinkedList

java.lang.Object
- components.linkedlist.LinkedListSecondary<T>
- - components.linkedlist.DoublyLinkedList<T>

Type Parameters:: T - the generic type of this

All Implemented Interfaces:: LinkedList<T>, LinkedListKernel<T>, Standard<LinkedList<T>>, java.lang.Iterable<T>

public class DoublyLinkedList<T>
extends LinkedListSecondary<T>

A non-layered implementation of a doubly-linked list using 2 sentinel nodes.

Author:

Matthew Shoemaker

Representation Invariant (concrete invariant of $this):

      [$this.preFront is not null]
      [$this.preFocus is not null]
      [$this.rear is not null]
      [$this.length >= 0]
      [$this.position < length]
      [$this.position = -1 if $this.length = 0]
      [$this.position = distance of this.focus from $this.preFront]
      [$this.preFocus points to the node just before the
          node containing the label that is in focus to
          the client if ($this.length > 0) and points to
          $this.preFront if $this.length = 0]
      [$this.preFront points to the leading sentinel node]
      [$this.postRear points to the trailing sentinel node]
      [$this.rear points to the node directly before $this.postRear]
      [$this.length = total number of nodes minus 2 for the sentinel nodes]

Abstraction Relation (interpretation mapping between $this and this):

      this = [label in nodes between, and not including, $this.preFront and $this.postRear]
      focus = [this.preFocus.next]

Constructor Summary

Constructors
Constructor and Description

DoublyLinkedList()
No-arg constructor for this.

Constructors
Constructor and Description
`DoublyLinkedList()` No-arg constructor for `this`.

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`void`	`add(T entry)` Appends `entry` to the end of #this.
`void`	`addToFront(T entry)` Adds `entry` to the front of #this.
`void`	`advance()` Shifts `#this.focus` forward by 1 position.
`void`	`clear()` Resets `this` to its initial value.
`T`	`focus()` Returns a reference to `#this.focus`.
`int`	`hashCode()` Note: Opted for a more efficient implementation.
`void`	`insert(T entry)` Inserts `entry` into `#this` at the position directly following the `#this.focus`.
`java.util.Iterator<T>`	`iterator()`
`int`	`length()` Returns the number of entries in `this`.
`void`	`moveToFront()` Shifts `this.focus` to the front of the list.
`void`	`moveToRear()` Moves `#this.focus` to the last entry in `this`.
`DoublyLinkedList<T>`	`newInstance()` Returns a new object with the same dynamic type as `this`, having an initial value.
`int`	`position()` Returns the position of `#this.focus`.
`T`	`remove()` Removes `this.focus` and returns it to the caller.
`T`	`removeRear()` Removes and returns the final entry in `this`.
`void`	`retreat()` Shifts `this.focus` to the entry previous to `#this.focus`.
`void`	`transferFrom(LinkedList<T> source)` Sets `this` to the incoming value of source, and resets `source` to an initial value; the declaration notwithstanding, the dynamic type of `source` must be the same as the dynamic type of `this`.

Methods inherited from class components.linkedlist.LinkedListSecondary
contains, equals, moveToPosition, removeFront, toString

Methods inherited from class java.lang.Object
getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface java.lang.Iterable
forEach, spliterator

- Constructor Detail
  - DoublyLinkedList
```
public DoublyLinkedList()
```
    No-arg constructor for this.
- Method Detail
  - add
```
public void add(T entry)
```
    Description copied from interface: LinkedListKernel
    
    Appends entry to the end of #this.
    
    Parameters:
    
    entry - item to be appended to this
  - addToFront
```
public void addToFront(T entry)
```
    Description copied from interface: LinkedListKernel
    
    Adds entry to the front of #this.
    
    Parameters:
    
    entry - item to be prepended to this
  - remove
```
public T remove()
```
    Description copied from interface: LinkedListKernel
    
    Removes this.focus and returns it to the caller. this.focus will be shifted to the right, and if #this.focus was the last entry, then this.focus shifts to the first entry in #this.
    
    Returns:
    
    #this.focus
  - removeRear
```
public T removeRear()
```
    Description copied from interface: LinkedList
    
    Removes and returns the final entry in this.
    
    Specified by:
    
    removeRear in interface LinkedList<T>
    
    Overrides:
    
    removeRear in class LinkedListSecondary<T>
    
    Returns:
    
    the final entry in this
  - advance
```
public void advance()
```
    Description copied from interface: LinkedListKernel
    
    Shifts #this.focus forward by 1 position.
  - retreat
```
public void retreat()
```
    Description copied from interface: LinkedListKernel
    
    Shifts this.focus to the entry previous to #this.focus.
  - moveToFront
```
public void moveToFront()
```
    Description copied from interface: LinkedListKernel
    
    Shifts this.focus to the front of the list.
  - length
```
public int length()
```
    Description copied from interface: LinkedListKernel
    
    Returns the number of entries in this.
    
    Returns:
    
    the number of entry of this
  - insert
```
public void insert(T entry)
```
    Description copied from interface: LinkedListKernel
    
    Inserts entry into #this at the position directly following the #this.focus.
    
    Parameters:
    
    entry - entry to be inserted into the list
  - focus
```
public T focus()
```
    Description copied from interface: LinkedListKernel
    
    Returns a reference to #this.focus.
    
    Returns:
    
    #this.focus
  - moveToRear
```
public void moveToRear()
```
    Description copied from interface: LinkedListKernel
    
    Moves #this.focus to the last entry in this.
  - position
```
public int position()
```
    Description copied from interface: LinkedListKernel
    
    Returns the position of #this.focus.
    
    Returns:
    
    the distance of this.focus fron the front of the list
  - iterator
```
public java.util.Iterator<T> iterator()
```
  - clear
```
public void clear()
```
    Description copied from interface: Standard
    
    Resets this to its initial value.
  - transferFrom
```
public void transferFrom(LinkedList<T> source)
```
    Description copied from interface: Standard
    
    Sets this to the incoming value of source, and resets source to an initial value; the declaration notwithstanding, the dynamic type of source must be the same as the dynamic type of this. If the type T has a no-argument constructor, then source satisfies the contract of the no-argument constructor for T. If T does not have a no-argument constructor, then source satisfies the contract of the constructor call that was used to initialize #source.
    
    Parameters:
    
    source - object whose value is to be transferred
  - newInstance
```
public DoublyLinkedList<T> newInstance()
```
    Description copied from interface: Standard
    
    Returns a new object with the same dynamic type as this, having an initial value. If the type T has a no-argument constructor, then the value of the new returned object satisfies the contract of the no-argument constructor for T. If T does not have a no-argument constructor, then the value of the new returned object satisfies the contract of the constructor call that was used to initialize this.
    
    Returns:
    
    new object "like" this with an initial value
  - hashCode
```
public int hashCode()
```
    Note: Opted for a more efficient implementation.
    
    Overrides:
    
    hashCode in class LinkedListSecondary<T>

Class DoublyLinkedList<T>

Constructor Summary

Method Summary

Methods inherited from class components.linkedlist.LinkedListSecondary

Methods inherited from class java.lang.Object

Methods inherited from interface java.lang.Iterable

Constructor Detail

DoublyLinkedList

Method Detail

add

addToFront

remove

removeRear

advance

retreat

moveToFront

length

insert

focus

moveToRear

position

iterator

clear

transferFrom

newInstance

hashCode