An array that uses a shadow array method to expand the underlying array data structure Should be Constant Time, independent of the size of the arrays

ShadowArray.java

public class ShadowArray<E> implements ShadowArrayInterface<E>{
  
	private E[] k;
	private E[] s;
	private int numItems;
	private int carryIndex;
	
	static final int INIT_SIZE = 5;
	
	@SuppressWarnings("unchecked")
	public ShadowArray() {
		k = (E[])(new Object[INIT_SIZE]);
		s = (E[])(new Object[2*INIT_SIZE]);
		numItems = 0;
		carryIndex = 0;
	}
	
	@SuppressWarnings("unchecked")
	public void add(E item) {
		//try to add the next item to the end of the array
    		try {
      
      			//if the array isn't full, add the item to both the current array
      			//and the shadow array
			k[numItems] = item;
			s[numItems] = item;
			
      			//if this is an expanded array, copy down the previous elements
      			//to the new shadow array
			s[carryIndex] = k[carryIndex];
			
      			//implement indexes
			carryIndex++;
			numItems++;
      
		} catch (IndexOutOfBoundsException e) {
      		//if the current array is full, expand it
      
      			//set the current array to the shadow array
      			//and create a new shadow array with double the length
			k = s;
			s = (E[])(new Object[2*k.length]);
			
      			//return the index to copy to 0
			carryIndex = 0;
			
      			//add the new item
			k[numItems] = item;
			s[numItems] = item;
      
      			//carry down the first item in the current array
			s[carryIndex] = k[carryIndex];
			
      			//increment indexes
			carryIndex++;
			numItems++;
		}
	}

ShadowArrayNoTryCatch.java

public class ShadowArray<E> implements ShadowArrayInterface<E>{
  
	private E[] k;
	private E[] s;
	private int numItems;
	private int carryIndex;
	
	static final int INIT_SIZE = 10;
	
	@SuppressWarnings("unchecked")
	public ShadowArray() {
		k = (E[])(new Object[INIT_SIZE]);
		s = (E[])(new Object[2*INIT_SIZE]);
		numItems = 0;
		carryIndex = 0;
	}
	
	@SuppressWarnings("unchecked")
	public void add(E item) {
		if (numItems >= k.length) {
			k = s;
			s = (E[])(new Object[2*k.length]);
			
			carryIndex = 0;
			
			k[numItems] = item;
			s[numItems] = item;
			
			s[carryIndex] = k[carryIndex];
		}
		else {
			k[numItems] = item;
			s[numItems] = item;
			
			s[carryIndex] = k[carryIndex];
		}
		
		carryIndex++;
		numItems++;
	}

Have you thought about implementing the shadow array method with add(int pos, E item)?