Question

Given a ListItem class, complete main() using the built-in LinkedList type to create a linked list called shoppingList. The program should read items from input (ending with -1), adding each item to shoppingList, and output each item in shoppingList using the printNodeData() method.

Ex. If the input is:

the output is:

--ShoppingList.java:

import java.util.Scanner;

import java.util.LinkedList;

public class ShoppingList {

   public static void main (String[] args) {

      Scanner scnr = new Scanner(System.in);

      // TODO: Declare a LinkedList called shoppingList of type ListItem

      String item;

      

      // TODO: Scan inputs (items) and add them to the shoppingList LinkedList

      //       Read inputs until a -1 is input

     

      

      // TODO: Print the shoppingList LinkedList using the printNodeData() method

    

   }

}

--ListItem.java:

public class ListItem {

    private String item;

    public ListItem() {

        item = "";

    }

    public ListItem(String itemInit) {

        this.item = itemInit;

    }

    // Print this node                                                                                   

    public void printNodeData() {

        System.out.println(this.item);

    }

}

Answer 1

public class ShoppingList {

   

public static void main (String[] args) {

      Scanner scan = new Scanner(System.in);

      // TODO: Declare a LinkedList called shoppingList of type ListItem

      LinkedList <ListItem> shoppingList = new LinkedList<ListItem>();

      ListItem temp;

      String item;

      item = "0";

      // TODO: Scan inputs (items) and add them to the shoppingList LinkedList

      //       Read inputs until a -1 is input

     

      while(!item.equals("-1")) {

      item = scan.next();

      if(item.equals("-1")) {

      break;

      }else {

      temp = new ListItem(item);

      shoppingList.add(temp);

      }

      }

      // TODO: Print the shoppingList LinkedList using the printNodeData() method

    for(int i = 0; i < shoppingList.size(); i++) {

    shoppingList.get(i).printNodeData();

    }

  }

}