Question

1. Open BlueJ and create a new project (Project->New Project...).
2. Create a new class named ListsDemo.
3. Open the source code and delete all the boilerplate code.
4. Type in the code to type (code to type with bigger font) exactly as shown, filling in your name and the date in the places indicated.
   • The code is provided as an image because you should type it in rather than copy-paste. If you need the code as text for accessibility, such as using a screen reader, ask the instructor.
5. the code to type is
6. 
   1 import java.util.ArrayList; * Demo using an ArrayList 5@author (put your name here) 6@version (put the date here) public class L13ts bemo private ArrayList<String> list; // declare a list (does not create the list) 10 12 13 14 15 *Constructor for objects of class ArrayListDemo public ListsDemo () list-new ArrayList<StringsO: 1I create an empty list 17 18 19 21 public void useList () 23 // add elements to the list String blueColor"blue" list.add (blueColor) list.add ("yellow") 25 26 27 28 29 30 31 32 System.out.println("The list has"list.size +" elements" System.out.println ("The first element is"+ list.get (0) String removedColor list. remove (0); System.out.println ("Removed element "+ removedColor); System.out.printin("Now the list has"+ list.size) + " elements") 35 36
   
7. Compile the code and be sure there are no errors. If there is an error, double-check what you typed compared to the code given.
8. Create a ListsDemo object and run the method.
   • Compare what you see output to the source code and try to understand what each statement is doing.
   • Review the code statements that don't cause output as well and understand what they are doing.
9. Take a screenshot to show you completed this part:
   • Open the source code window and put the terminal window showing the output from running it nearby. (Overlapping the windows is okay.)

Answer 1

/**********************************************ListDemo.java********************************/

import java.util.ArrayList;

/**
* Demo using an ArrayList
*
* @author JUGAL KISHOR SAINI
* @version April,29,2019
*/
public class ListDemo {

   private ArrayList<String> list;

   public ListDemo() {
      
       list = new ArrayList<String>();
   }
  
   public void useList() {
      
       String blueColor = "blue"; //creating a string object
       list.add(blueColor); //add string to array list
       list.add("yellow"); //add String to array list
       /*
       * print the size of list
       * print the first element
       */
       System.out.println("The list has "+list.size()+" elements");
       System.out.println("The first element is "+ list.get(0));
       /*
       * remove the first element of list
       * print removed color from list
       * print number of element in the list
       */
       String removedColor = list.remove(0);
       System.out.println("Removed element "+removedColor);
       System.out.println("Now the list has "+list.size()+" elements");
   }
  
   public static void main(String[] args) {
       /*
       * create object of ListDemo
       */
       ListDemo listDemo = new ListDemo();
       /*
       * use method of ListDemo
       */
       listDemo.useList();
   }
  
}

/**********************************output*************************/

38 390public static void main(String1 40 41 42 43 main(Stringt] args) f args) create object of ListDemo ListDemo listDemo-new ListDemo (); *use method of ListDemo 45 46 47 48 49 listDemo.useList);

The list has 2 elements
The first element is blue
Removed element blue
Now the list has 1 elements

ConsoleX <terminated> ListDemo [Java Application] C:\Program F The list has 2 elements The first element is blue Removed element blue Now the list has 1 elements

B Console X D ListDemo.java Χ 1 import java.util.ArrayList; <terminated> ListDemo [Jav The list has 2 elements The first element is blue Removed element blue Now the list has 1 elemen Demo using an ArrayList 4 Qauthor JUGAL KISHOR SAINI 5 eversion April, 29,2019 7 public class ListDemo private ArrayList<string> list; public ListDemo) 18 list = new ArrayList<string>(); public void uselist) string bluecolor-"blue"; //creating a string object list.add(bluecolor); //add string to array list list.add("yellow"); //add String to array list 13 14 15 *print the size of list print the first element System.out.println("The list has "+list.size+" elements" System.out.println("The first element is list.get(e)) 21 s remove the first element of list *print removed color from list 23 24 25 26 27 28 29 30 print number of element in the list string removedColor = list.remove(e); System.out.println(" Removed element "+removedcolor); System.out.println("Now the list has "+list.size()+" elements") public static void main(string[] args) create object of ListDemo 히 ListDemo listoemo = new Listoemo(); 36 s use method of ListDemo 38 39 listDemo.useList); 42 43

Thanks a lot, Please let me know if you have any problem.........