Question

JAVA ONLY - Complete the code

import java.util.Scanner;


/**
 * This program will use the HouseListing class and display a list of
 * houses sorted by the house's listing number
 * 
 * Complete the code below the numbered comments, 1 - 4. DO NOT CHANGE the
 * pre-written code
 * @author 
 *
 */

public class HouseListingDemo {

    public static void main(String[] args) {
       Scanner scan = new Scanner(System.in);
        HouseListing[] list;
        String listNumber, listDesc;
        int count = 0;
        double listPrice;
        String output;
        
        double mostExpensive;
        
         do{
            System.out.print("Enter the number of houses --> ");
           count = scan.nextInt();
        }while(count < 1);
         
        /* 1.
         * create an array of HouseListing objects using the variable that holds
         * the user's response to the prompt above
         */
        
        
        // for loop loads the array with HouseListing's constructor
        for (int i = 0; i < list.length; i++) 
        {
           System.out.println("\n***HOUSE " + (i+1) + "***");
           // Prompt for house listing #
           System.out.print("Enter house listing " +
                   "number (Alphanumeric) #"+ (i+1) +": ");
           listNumber = scan.next();
           
           // Clear buffer
           scan.nextLine();
           
           // Prompt for house description
           System.out.print("Enter description for " +
                   "house #" +(i+1) + ": ");
           listDesc = scan.nextLine();
           
           // Prompt for house price
           System.out.print("Enter listing price for " 
                   + "house #" +(i+1) + ": ");
           listPrice = scan.nextDouble();
           
            /* 2.
             * create a HouseListing object using the input values and store/load
             * the object in the array
             */
        }
        
        
        /* 3.
         * Assign the 0th element of the array to the most expensive house
           think ... you can't assign an object to a price but the object
           has a method that may help you here ... 
         */
        
        
        output = "Listings:\n";
        /*
         * loop below builds the output string
         */
        for (int i = 0; i < list.length; i++) {
            output += list[i] + "\n";
            
            /* 4.
              Using a control structure, find and the store the double varaible
              which holds the most expensive house (We don't need to listing #)
              JUST THE PRICE
            */
        }
        // output
         System.out.println(output);
        System.out.println("The most expensive house on the market costs: $" 
        + mostExpensive);
    }
}

Answer 1

HI,

Below are classes..i completed the all 4 points which you asekd to do.

HouseListing.java

public class HouseListing
{

    private  int num;

    private  String listNumber;

    private  String listDesc ;
        
        private double listPrice;

  //  constructor
    

        public HouseListing(int num, String listNumber, String listDesc, double listPrice){
      //System.out.println("arrgument constructor");
          this.num = num;
      this.listNumber = listNumber;
          this.listDesc = listDesc;
          this.listPrice = listPrice;
    }

   
     // Accessors
     public int getNum()
     {

       return num;

     }

  

     public String getListNumber()
     {
       
       return listNumber;

     }

  

      public String getListDesc()
      {

        return listDesc;

      }

          public double getListPrice()
      {

        return listPrice;

      }

          
 // If not given something to compare by, compares by title.
// NOTE: The natural ordering given by this function is inconsistent with equals
    // public double compareTo(HouseListing other) {
      //  double compareprice =((HouseListing)other).getListPrice();
     //   return this.listPrice-compareprice;
   ///  }
  
      

      @Override

      public String toString()
      {

        return listNumber + "\t" + listDesc + "\t"+listPrice ;

      }

}

HouseListingDemo.java

import java.util.Scanner;
import java.util.List;
import java.util.Collections;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.*;




public class HouseListingDemo {

    public static void main(String[] args) {
       Scanner scan = new Scanner(System.in);
        HouseListing[] list;
        String listNumber, listDesc;
        int count = 0;
        double listPrice;
        String output;
        
        double mostExpensive=0;
        
         do{
            System.out.print("Enter the number of houses --> ");
           count = scan.nextInt();
        }while(count < 1);
         
        /* 1.
         * create an array of HouseListing objects using the variable that holds
         * the user's response to the prompt above
         */
        list = new HouseListing[count];
        
        // for loop loads the array with HouseListing's constructor
        for (int i = 0; i < list.length; i++) 
        {
           System.out.println("\n***HOUSE " + (i+1) + "***");
           // Prompt for house listing #
           System.out.print("Enter house listing " +
                   "number (Alphanumeric) #"+ (i+1) +": ");
           listNumber = scan.next();
           
           // Clear buffer
           scan.nextLine();
           
           // Prompt for house description
           System.out.print("Enter description for " +
                   "house #" +(i+1) + ": ");
           listDesc = scan.nextLine();
           
           // Prompt for house price
           System.out.print("Enter listing price for " 
                   + "house #" +(i+1) + ": ");
           listPrice = scan.nextDouble();
           
            /* 2.
             * create a HouseListing object using the input values and store/load
             * the object in the array
             */
                         HouseListing hl = new HouseListing((i+1), listNumber, listDesc, listPrice);
                         list[i] = hl;
        }
        
        
        /* 3.
         * Assign the 0th element of the array to the most expensive house
           think ... you can't assign an object to a price but the object
           has a method that may help you here ... 
         */

                 //converted array in list to us the sort method with comparerator to get price in descending  order
                 List<HouseListing> arr_list = Arrays.asList(list); 
        
                 Collections.sort(arr_list, new Comparator<HouseListing>(){
         @Override
          public int compare(HouseListing h1, HouseListing h2) {

             /* if (h1.getListPrice().compareTo(h2.getListPrice()) < 0) //this comes 1st
                 return -1;
              else if (h1.getListPrice().compareTo(h2.getListPrice()) > 0) //temp comes 1st
                 return 1;
              else //if both are equal
                 return 0;   */
                                 
              if (h2.getListPrice() < h1.getListPrice())
                 return -1;
              else if(h2.getListPrice() > h1.getListPrice())
                 return 1;
              else
                 return 0;


                        }
        });
        

                
        
        output = "Listings:\n";
        /*
         * loop below builds the output string
         */
        for (int i = 0; i < list.length; i++) {
            output += list[i] + "\n";
            
            /* 4.
              Using a control structure, find and the store the double varaible
              which holds the most expensive house (We don't need to listing #)
              JUST THE PRICE
            */
        }

        // after sorting we will get most expensive house always at index 0 of array list.
                 mostExpensive = ((HouseListing)list[0]).getListPrice();
         System.out.println(output);
         System.out.println("The most expensive house on the market costs: $" 
        + mostExpensive);
    }
}

Thanks