LAB: Sorted number list implementation with linked lists

Step $1$: Inspect the Node.java file

Inspect the class declaration for a doubly$-$linked list node in Node.java. Access Node.java by clicking on the orange arrow next to LabProgram.java at the top of the coding window. The Node class has three fields:

a double data value,

a reference to the next node, and

a reference to the previous node.

Each field is protected. So code outside of the class must use the provided getter and setter methods to get or set a field.

Node.java is read only, since no changes are required.

Step $2$: Implement the insert$()$ method

A class for a sorted, doubly$-$linked list is declared in SortedNumberList.java. Implement the SortedNumberList class's insert$()$ method. The method must create a new node with the parameter value, then insert the node into the proper sorted position in the linked list. Ex: Suppose a SortedNumberList's current list is $23->47\mathrm{.}25->86,$ then insert$(33\mathrm{.}5)$ is called. A new node with data value $33\mathrm{.}5$ is created and inserted between $23$ and $47\mathrm{.}25,$ thus preserving the list's sorted order and yielding: $23->35\mathrm{.}5->47\mathrm{.}25->86$

Step $3$: Test in develop mode

Code in main$()$ takes a space$-$separated list of numbers and inserts each into a SortedNumberList. The list is displayed after each insertion. Ex: If input is

$7715-4263\mathrm{.}5$

then output is:

List after inserting $77$:

$77$

List after inserting $15$:

$1577$

List after inserting $-42$:

$-421577$

List after inserting $63\mathrm{.}5$:

$-421563\mathrm{.}577$

Try various program inputs, ensuring that each outputs a sorted list.

Step $4$: Implement the remove$()$ method

Implement the SortedNumberList class's remove$()$ method. The method takes a parameter for the number to be removed from the list. If the number does not exist in the list, the list is not changed and false is returned. Otherwise, the first instance of the number is removed from the list and true is returned.

Uncomment the commented$-$out part in main$()$ that reads a second input line and removes numbers from the list. Test in develop mode to ensure that insertion and removal both work properly, then submit code for grading. Ex: If input is

$84721961$

$1984$

then output is:

List after inserting $84$:

$84$

List after inserting $72$:

$7284$

List after inserting $19$:

$197284$

List after inserting $61$:

$19617284$

List after removing $19$:

$617284$

List after removing $84$:

$6172$

LabProgram.java

import java.util.Scanner;

public class LabProgram $\{$

$//$ Prints the SortedNumberList's contents, in order from head to tail

public static void printsList$($SortedNumberList list$)\{$

Node node $=$ list.head;

while $($node $!=$ null$)\{$

System.out.print$($node$.$getData$()+"")$;

node $=$ node.getNext$()$;

$\}$

System.out.println$()$;

$\}$

public static void main$($String$[]$ args$)\{$

Scanner scnr $=$ new Scanner$($System$.$in$)$;

String inputLine;

SortedNumberList list $=$ new SortedNumberList$()$;

$//$ Read the first line of inputs and insert each number into the list

inputLine $=$ scnr$.$nextLine$()$;

String$[]$ inputs $=$ inputLine.split$("")$;

for $($String input : inputs$)\{$

double number $=$ Double.parseDouble$($input$)$;

list.insert$($number$)$;

printList$($list$)$;

$\}$

$//$ Read the second line of inputs and remove each number from the list

if $($scnr$.$hasNextLine$())\{$

inputLine $=$ scnr$.$nextLine$()$;

inputs $=$ inputLine.split$("")$;

for $($String input : inputs$)\{$

double number $=$ Double.parseDouble$($input$)$;

list.remove$($number$)$;

printList$($list$)$;

$\}$

$\}$

scnr$.$close$()$;

$\}$

$\}$

Node.java

public class Node $\{$

protected double data;

protected Node next;

protected Node previous;

$//$ Constructs this node with the specified numerical data value. References to the next

$//$ and previous nodes are assigned null.

public Node$($double initialData$)\{$

data $=$ initialData;

next $=$ null;

previous $=$ null;

$\}$

$//$ Constructs this node with the specified numerical data value, references to the next

$//$ and previous nodes.

public Node$($double initialData, Node nextNode, Node previousNode$)\{$

data $=$ initialData;

next $=$ nextNode;

previous $=$ previousNode;

$\}$

$//$ Returns this node's data.

public double getData$()\{$

return data;

$\}$

$//$ Sets this node's data.

public void setData$($double newData$)\{$

data $=$ newData;

$\}$

$//$ Gets the reference to the next node.

public Node getNext$()\{$

return next;

$\}$

$//$ Sets the reference to the next node.

public void setNext$($Node newNext$)\{$

next $=$ newNext;

$\}$

$//$ Gets the reference to the previous node.

public Node getPrevious$()\{$

return previous;

$\}$

$//$ Sets the reference to the previous node.

public void setPrevious$($Node newPrevious$)\{$

previous $=$ newPrevious;

$\}$

$\}$

SortedNumberList.java

public class SortedNumberList $\{$

java please