Question

In this assignment, you will be practicing the Java OOP skills we've learned this week in implementing a customized mutable Array class. Please read the following requirements carefully and then implement your own customized Array class:

=== 1) Basic (100' pts total) ===

Your Array class must provide the following features:

--1.1) (20' pts) Two constructors. One takes the input of the initialized capacity (int) and create the underlying array with that capacity; the other takes no input and creates an array that can hold a single element by default (that is, init capacity == 1);

--1.2) (20' pts) Getters and setters and basic methods we discussed during the class including: getCapacity(), getSize(), set(int index, E val), get(int index), isEmpty();

--1.3) (20' pts) CRUD operations we discussed during the class including: add(int index, E val), addLast(), addFirst(), remove(int index), removeLast(), removeFirst(), removeElement(int target), removeAll(int target);

--1.4) (20' pts) Supports generic types;

--1.5) (20' pts) Mutable, that is when add element exceeding its capacity, it can resize to accommodate the change.

=== 2) Bonus (20' pts total) ===

2.1) (10' pts) Implement a (private or public) swap(int a, int b) method that swaps the two elements in the index a and b if a and b are both admissible; also a public reverse() method that reverses the order of stored elements in-place (means, no additional spaces are allocated).

2.2) (10' pts) A public void sort() method sorts the stored elements in ascending order inO(nlog(n)) time.

[hint]: Quicksort or Merge sort

Answer 1

import java.util.*;
import java.lang.*;

// Generic class
public class Array<T>{
  
   static Object[] array = null; // Generic array
   static int capacity = 0; // declare variable
  
// Class constructor
   Array(int capacity){
       this.capacity = capacity;
       array = new Object[capacity];
   }
// Class constructor
   Array() {
       this.capacity = 1;
       array = new Object[1];
   }
// getCapacity method
   static int getCapacity() {
       return capacity;
   }
// getSize method
   static int getSize() {
       return array.length;
   }
// set method
   static void set(int index, Object val) {
       array[index] = val;
   }

// get method

   static Object get(int index) {
       return array[index];
   }
isEmpty method
   static boolean isEmpty() {
       if(array.length == 0) return true;
       else return false;
   }
// swap method
   static void swap(int a, int b) {
       Object temp;
       temp = array[a];
       array[a] = array[b];
       array[b] = temp;
   }
// reverse method
   static void reverse() {
       Arrays.sort(array,Collections.reverseOrder());
   }
// sort method
   static void sort() {
       Arrays.sort(array);
   }
// insertArray method
   static void insertArray() {
       for(int i=0; i<capacity; i++) {
           array[i] = i;
       }
   }
  
   public static void main(String[] args) {

       Array obj = new Array(20); // Create Array class object
      
       insertArray(); // Call insertArray method
      
       System.out.println(obj.getCapacity()); // Call getCapacity method
       System.out.println(obj.getSize()); // Call getSize method
       obj.set(4,2); // Call set method
       System.out.println(obj.get(4)); // Call get method
       System.out.println(obj.isEmpty()); // Call isEmpty method
       obj.swap(2,4); // Call swap method
       obj.reverse(); // Call reverse method
       obj.sort(); // Call sort method

   }

}