Question

Need help with this Java. I need help with the "to do" sections. Theres two parts to this and I added the photos with the entire question

Lab14 Part 1:

1) change the XXX to a number in the list, and YYY to a number
// not in the list

2.code a call to linearSearch with the item number (XXX)
// that is in the list; store the return in the variable result

3. change both XXX numbers to the number searched for

4. code a call to linearSearch with the item number (yyy)
// that is not in the list; store the return in the variable result

5. change both YYY to the number searched for

6. code to sort the array using the Collections class

7. change the AAA to a number in the list, and BBB to a number
// not in the list (use two different numbers)

8. code a call to binarySearch with the item number (AAA)
// that is in the list; store the return in the variable result

0. change both AAA numbers to the number searched for

10. code a call to binarySearch with the item number (BBB)
// that is not in the list; store the return in the variable result

11. change both BBB numbers to the number searched for

public class ItemList { /** This is the main process for the project */ public static void main() { System.out.println("\n\tBegin Item List Demo\n"); System.out.println("Declare an ArrayList to hold Item objects"); ArrayList<Item> list = new ArrayList<Item>(); try { System.out.println("\n Add several Items to the list"); list.add(new Item(123, "Statue)); list.add(new Item(332, "Painting")); list.add(new Item(241, "Figurine")); list.add(new Item(126, "Chair")); list.add(new Item(411, "Model")); list.add(new Item(55, "Watch")); System.out.println("\nDisplay original Items list:"); list Items (list): int result = -1; 1 1. TO DO: change the XXX to a number in the list, and YYY to a number not in the list (1 pt) System.out.println("\nLinear Search list for items XXX and YYY:"); 1/ 2. TO DO: code a call to linear Search with the item number (XXX) that is in the list; store the return in the variable result (2 Pts) if(result >= 0) 13. TO DO: change both XXX numbers to the number searched for (1 Pt) System.out.printf("Item XXX found at pos %d\n", result); else System.out.printf("Item XXX not found in list\n"); // // 4. TO DO: code a call to linear Search with the item number (yyy) that is not in the list; store the return in the variable result (2 Pts)

$1/ 11. TO DO change both BBB numbers to the number searched for (1 Pt) System.out.printf(Item BBB found at pos %d\n, result$

Answer 1

All To Do sections of the given code are completed and indicated with their respective To do numbers as comments.

Sample output is added at the end.

Code:

ItemList.java:

import java.util.ArrayList;
import java.util.Collections;

public class ItemList {

    public static void main(String[] args)
    {
        System.out.println("\n\tBegin Item List Demo\n");

        System.out.println("Declare an ArrayList to hold Item Objects");
        ArrayList<Item> list =new ArrayList<Item>();

        try
        {
            System.out.println("\n Add several Items to the list");
            list.add(new Item(123, "Statue"));
            list.add(new Item(332, "Painting"));
            list.add(new Item(241, "Figurine"));
            list.add(new Item(126, "Chair"));
            list.add(new Item(411, "Model"));
            list.add(new Item(55, "Watch"));

            System.out.println("\nDisplay original Items list:");
            listItems(list);

            int result = -1;
            // 1
            System.out.println("\nLinear Search list for items 332 and 421:");

            //2
            result=linearSearch(list,332);
            if(result >= 0){
                //3
                System.out.printf("Item 332 found at pos %d\n",result);
            }
            else
                System.out.printf("Item 332 not found in the list");

            //4
            result=linearSearch(list,421);

            if(result >= 0){
                //5
                System.out.printf("Item 421 found at pos %d\n",result);
            }
            else
                System.out.printf("Item 421 not found in the list");

            System.out.println("\nSort list into Item number sequence");
            //6
            Collections.sort(list);

            System.out.println("\nDisplay the Sorted Items list:");
            listItems(list);

            //7
            System.out.println("Binary Search list for items 126 and 200:");

            //8
            result=binarySearch(list,126);
            if(result >= 0){
                //9
                System.out.printf("Item 126 found at pos %d\n",result);
            }
            else {
                System.out.printf("Item 126 not found in the list");
                System.out.printf("Should be at pos %d\n", -result - 1);
            }

            //10
            result=binarySearch(list,200);

            if(result >= 0){
                //11
                System.out.printf("Item 200 found at pos %d\n",result);
            }
            else {
                System.out.printf("Item 200 not found in the list\n");
                System.out.printf("Should be at pos %d\n", -result - 1);
            }


        } catch (Exception e) {
            System.out.println(e.getMessage());
        }

        System.out.println("\n\tEnd Item List Demo\n");

    }

    public static int linearSearch(ArrayList<Item> list, int number)
    {
        for(int i=0; i<list.size();i++)
            if(list.get(i).getItemNo() == number)
                return i;

        return -1;
    }

    public static void listItems(ArrayList<Item> list)
    {
        for(Item item : list)
            System.out.println(item.toString());
    }

    public static int binarySearch(ArrayList<Item> list, int key){

        int low =0;
        int high=list.size() - 1;
        int pos = 0;

        while(high >= low)
        {
            pos = (low + high) / 2;
            if (key < list.get(pos).getItemNo())
                high=pos-1;
            else if (key == list.get(pos).getItemNo())
                return pos;
            else
                low = pos + 1;
        }
        return -low -1;
    }
}

Item.java:

public class Item implements Comparable<Item>{


    private int itemNo;

    private String itemDesc;

    public Item()
    {
        itemNo = 0;
        itemDesc = "";
    }

    public Item(int number, String desc) throws Exception
    {
        setItemNo(number);
        setItemDesc(desc);
        this.itemDesc = itemDesc;
    }

    public int getItemNo() {
        return itemNo;
    }

    public void setItemNo(int number) throws Exception {

        if (itemNo == 0) {
            if (number > 0)
                itemNo = number;
            else
                throw new Exception("Item number must be greater than (0)");
        } else {
            throw new Exception("An existing nymber cannot be changed!");
        }
    }

    public String getItemDesc() {
        return itemDesc;
    }

    public void setItemDesc(String desc) throws Exception {
        if(desc.trim().length() > 0)
            itemDesc=desc;
        else
            throw new Exception("Item description cannot be blank");
    }

    public boolean equals(Item other){
        return  (itemNo == other.itemNo);
    }

    @Override
    public int compareTo(Item other) {
        return itemNo - other.itemNo;
    }

    @Override
    public String toString() {
        return String.format("%4d %-25s",itemNo,itemDesc);
    }
}

Output of ItemList.java:

Begin Item List Demo Declare an ArrayList to hold Item Objects Add several Items to the list Display original Items list: 123 Statue 332 Painting 241 Figurine 126 Chair 411 Model 55 Watch Linear Search list for items 332 and 421: Item 332 found at pos 1 Item 421 not found in the list Sort list into Item number sequence

Display the Sorted Items list: 55 Watch 123 Statue 126 Chair 241 Figurine 332 Painting 411 Model Binary Search list for items 126 and 200: Item 126 found at pos 2 Item 200 not found in the list Should be at pos 3 End Item List Demo Process finished with exit code o