You will be using a linked-list and recursion in the back-end. Watch out for the following

• Instead of using an array you will use a linked list of houses created by you from scratch. This list will be called HList.java.
  • HList is a linked list of HNodes which will contain a House object.
• When printing the list you will do it using recursion.

Instructions:

Using the HouseException.java and the House.java from A01-Houseyou will implement a driver class called HouseListing.java to manipulate a Linked list (HList) of Home objects. This time, again, you will be creating the driver class.

• Using linked lists to manipulate objects
• using recursion to print linked lists

HNode.java - node containing a House object. (total of 120 points distributed as shown below) Note that the method UML description is listed below and it should be implemented exactly as it is.

• +HNode( ) - constructor, takes no parameters. (20 points)
• +setNext(HNode n): void (20 points)
• +getNext( ): HNode (20 points)
• +setHouse(House h): void (20 points)
• +getHouse( ): House (20 points)
• +toString( ): String (20 points)

You do not need a Node exception because the House is already validated with the HouseException. However, you may write it and submit it, if your design requires it. Please comment on your design.

HList.java -list of HNodes - list of nodes containing House objects (270 points) This class works directly with the driver class to implement each one of the menu options and to create the list object.

• +HList( ) constructor, takes no parameters, initializes list, instance variables and references (20 points)
• +add(House): void adds a HNode to the list. You may choose to send an HNode or a House as a parameter. It depends on how you design your code. Just add a comment about your design choices. This method will be called to implement the add house option from the menu. (75 points)
• +remove(int MLS): boolean removes the house with the given MLS, if it exists. This method will be called to implement the remove house option from the menu. (75 points)
• +printAllHouses( ):void prints all the houses in the list. This method is called to implement option 4. Must be a recursive method (50 points, If you create a non-recursive method you will only get 25 points).
• +printHousesLessThan(double price):void prints the houses priced less than the parameter given.It implements option 3. Must be a recursive method. (50 points, If you create a non-recursive method you will only get 25 points).

Driver class HouseListing.java

When your code begins execution the following menu should be displayed.

1. add a house 2. remove a house 3. print houses that cost less than a given price 4. print all the houses 0. end this program

Your driver class should:

• be named: HouseListing.java
• work with your Home.java and HomeException.java (fix them if you did not get full credit, otherwise you will lose even more points this time)
• validate user input. Your code should not crash.
• create an HList object to manipulate Nodes and House objects

Implementing the menu options

1. add a house (call the add method) 2. remove a house (call the remove method) 3. print houses that cost less than a given price (call the printHousesLessThan method) 4. print all the houses (call the printAllHouses method) 0. end this program

Implementing the looping menu in the driver class:

• Your code should continue to loop until the user selects 0. If the program terminates at any other point for any other reason you will lose these points. (10 points).
• If the user enters an out of range number, you should print a carefully crafted error message explaining the problem and loop into the menu again. (10 points).
• If the user enters anything other than a number, you should catch the exception, print a carefully crafted error message explaining the problem and loop into the menu again. (10 points).

Your code should always continue to loop until the user selects 0.

Other considerations

• The linked-list should not contain duplicate house MLSs at any time.
• You should not use any of the linked-list methods implemented by Java. Everything should be done from scratch by you.
  • If you need to import anything to make your linked list work then you are doing it the wrong way. Follow the lecture!
  • If you have any questions please send me an email.
• You should use the proper exceptions, like InputMismatchException or HouseException, NullPointerException etc as appropriate
• You may use only ONE linked list for this assignment. This should be a linked list of HNodes containing House objects.
• You may implement extra methods to get this assignment done, however you MUST have the required methods to get the points listed.

When you submit your assignment, you MUST submit the following:

• HouseListing.java <----- This must be the driver class.
• HList.java
• HNode.java
• House.java (must resubmit) (10 points, if incorrect will lose 20points)
• HouseException.java (must resubmit) (10 points, if incorrect will lose 20points)

any other classes you implemented for this assignment must be submitted as well.

You must Follow the Java coding standards and put your name at the top of your code. (20 points)

Here is the House.java

import java.io.*; import java.util.*;

public class House{ //Instance variables private int mls; private int bedrooms; private double price; private String seller; //Getters and Setters for mls public int getMls() { return mls; } public void setMls(int mls)throws HouseException { if(mls<10001 || mls>99999) { HouseException e = new HouseException(); e.setMessage("Program terminated!! mls value should be between 10001 and 99999 "); throw e; } this.mls =mls; } //Getters and Setters for bedrooms public int getBedrooms() { return bedrooms; } public void setBedrooms(int bedrooms) throws HouseException { if(bedrooms<0 || bedrooms>5) { HouseException e = new HouseException(); e.setMessage("Program terminated!! bedroom value should be between 0 and 5 "); throw e; } this.bedrooms = bedrooms; } //Getters and Setters for price public double getPrice() { return price; } public void setPrice(double price) throws HouseException { if(price<0 || price>1000000) { HouseException e = new HouseException(); e.setMessage("Program terminated!! Price value should be between 0 and 1000000"); throw e; } this.price = price; } //Getters and Setters for seller public String getSeller() { return seller; } public void setSeller(String seller) throws HouseException{ int length = seller.length(); int no_of_valid_characters =0; for(int i=0;i

Here is the HouseException.java

import java.io.*; import java.util.*;

public class HouseException extends Exception{ //instance variable String message; //Empty constructor public HouseException() { } public void setMessage(String message) { this.message =message; } public String getMessage() { return message; } }

class Myclass { public static void main (String[] args) { Scanner sc = new Scanner(System.in); System.out.println("Enter mls:"); int mls =Integer.parseInt(sc.nextLine()); System.out.println("Enter no of bedrooms:"); int bedrooms =Integer.parseInt(sc.nextLine()); System.out.println("Enter the price $:"); double price =Integer.parseInt(sc.nextLine()); System.out.println("Enter seller name:"); String seller =sc.nextLine(); //Creating House object try { House h = new House(mls,bedrooms,price,seller); System.out.println("The Details are:"); System.out.println(h.toString()); } catch (HouseException e) { // TODO Auto-generated catch block System.out.println(e.getMessage()); } } }