Question

Implement a MyArrayList class similar to the java.util.ArrayList class using an array of objects. Although an array

Answer 1

program

import java.util.*;
import java.util.Scanner;
import java.util.Collections;
public class MyArrayList {
public static void main(String args[]) {
// create an array list
Scanner sc = new Scanner(System.in);
ArrayList<Integer> arr=new ArrayList<Integer>(16);
ArrayList<Integer> duplicateArray=new ArrayList<Integer>(32);
for (int i = 0; i < 16; i++) {
System.out.println("Enter number");
int num=sc.nextInt();
arr.add(num);
  
if(arr.size()>15){
break;
}
}
//adding elements to duplicate array
if(arr.size()>=15){
duplicateArray.addAll(arr);
}
//adding
arr.add(10,5);

//contains
boolean res = arr.contains(5);
if (res == true) {
System.out.println("element 5 is contained in the list");
}
else {
System.out.println("element 5 is not contained in the list");
}

// 5th element value retrieval
int val=arr.get(5);
System.out.println("Retrieve element is = " + val);   
  
/*// getting index of 5
val=arr.IndexOf(5);
System.out.println("The number 5 at index " + val);*/
  
//checking empty or not
res = arr.isEmpty();
if (res == true) {
System.out.println("empty");
}
else {
System.out.println("not empty");
}
  
// getting index of value 5
val=arr.lastIndexOf(5);
System.out.println("The index of 5 is " + val);
  
//removes at index 5
arr.remove(5);
  
// Remove 5
arr.remove(5);

// setting 55 to number at 5
arr.set(5,55);
// display the array list
System.out.println("arr has: " + arr);
System.out.println("\nduplicate array has: " + duplicateArray);
}
}

E] Terminal Enter number 15 Enter number 16 element 5 is contained in the list Retrieve element is 6 not empty The last occurrence of 5 is 10 arr has: [1, 2, 3, 4, 5, 55, 9, 1e, 5, 11, 12, 13, 14, 15, 16] duplicate array has: [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16] sh-4.3#