import java.util.NoSuchElementException;

public class GArrayQueue<E> implements GQueue<E>, Cloneable {
	//Data
	protected Object[] array;	//Elements
	protected int begin;		//First element
	protected int end;			//Last element
	protected int number;		//Number of elements

	//Constructors
	public GArrayQueue() { this(10); }
	
	public GArrayQueue(int n){
    	...
	}
	
	@SuppressWarnings("unchecked")
	public GArrayQueue(Object[] data) {
		this(data.length + 10);
		for(int i = 0; i < data.length; i++) add((E)data[i]);
	}

	//GQueue methods implementation
	public boolean isEmpty(){ return number == 0; }
	
	public boolean add(E x) throws IllegalStateException {
    	if(isFull()) throw new IllegalStateException();
		...
        return true;
    }
	
	@SuppressWarnings("unchecked")
	public E element() throws NoSuchElementException {
 		if(isEmpty()) throw new NoSuchElementException();
 		return (E)array[begin];
 	}
 	
	public E remove() throws NoSuchElementException {
 		E result = this.element();
 		...
   		return result;
 	}
 	 	
 	public boolean offer(E e) {
 		try {
 			this.add(e);
 			return true;
 		}catch(IllegalStateException ex) { return false; }
 	}
 	
 	public E peek() {
 		try {
 			return this.element();
 		}catch(NoSuchElementException e) { return null; }	
 	}
 		
 	public E poll() {
 		try {
 			return this.remove();
 		}catch(NoSuchElementException e) { return null; }	
 	}
 			
	public Object[] toArray() {
		Object[] result = new Object[number];
		...
        return result;
	}
	
	//Other methods
	public boolean isFull(){ return number >= array.length; }
	public int capacity() { return array.length; }
	
	//Override method
	@SuppressWarnings("unchecked")
    public Object clone() {
        GArrayQueue<E> copy = null;
        try {
            copy = (GArrayQueue<E>)super.clone();
            copy.array = this.array.clone();
            copy.begin = this.begin;
            copy.end = this.end;
            copy.number = this.number;
        } catch (java.lang.CloneNotSupportedException e) {}
        return copy;
    }
}