Queue.java

package org.disco.easyb.bdd;

import java.util.ArrayList;

public class Queue<E> {

    private ArrayList<E> list;

    public Queue() {
        this.list = new ArrayList<E>();
    }

    public void enqueue(E value) {
        if (value == null) {
            throw new RuntimeException("Can't enqueue a null value");
        }
        this.list.add(value);
    }

    public E dequeue() {
        if (this.list.isEmpty()) {
            throw new RuntimeException("Nothing to dequeue");
        } else {
            return this.list.remove(0);
        }
    }
}