Implement the ADT stack (named Stack274) using an array to stores the entries. This class must implement the textbooks StackInterface. Expand the array dynamically by 2X (i.e., a resizable array) when a push is called and the array is full.Also, reduce the size of the array (cut the array size in half) when a pop results in less than 25% of the array being used; the size of the array should always be at least 20. Maintain the stacks bottom entry in stack[stack.length-1].

public interface StackInterface {

/**

* Adds a new entry to the top of this stack.

*

* @param newEntry An object to be added to the stack.

*/

public void push(T newEntry);

/**

* Removes and returns this stack's top entry.

*

* @return The object at the top of the stack.

* @throws EmptyStackException if the stack is empty before the operation.

*/

public T pop();

/**

* Retrieves this stack's top entry.

*

* @return The object at the top of the stack.

* @throws EmptyStackException if the stack is empty.

*/

public T peek();

/**

* Detects whether this stack is empty.

*

* @return True if the stack is empty.

*/

public boolean isEmpty();

/** Removes all entries from this stack. */

public void clear();

public int size();

} // end StackInterface