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POFor each with my custom class won't work
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copied!<p>Hey everybody I'm working with Java.<br> So I am writing a class called <strong>OrderedSet</strong>. It is a class that is cross between a set and a queue. In other words, it is a queue without any duplicates. So I know I have to implement the <em>Iterable</em> interface, and write an iterator method. To write the method I have to then implement the <em>Iterator</em> interface.</p> <pre><code>package comp345; import java.util.Iterator; import java.util.NoSuchElementException; class OrderedSet implements Iterable<Object> { private Object[] queue; // This is how the OrderedSet is represented, a // queue of Objects private int counter; // Counter to keep track of current position of queue private int queueSize; // Keep track of the queue; // Constructor public OrderedSet(int size) { this.queue = new Object[size]; this.counter = 0; this.queueSize = size - 1; // Instantiate each instance of the object in the object array for (int i = 0; i < queue.length; i++) { queue[i] = new Object(); } } /** * Ensures that this collection contains the specified element. If it is not * already in the collection it is added it to the back of the queue. * * @param e * element whose presence in this collection is to be ensured * @return true if this collection changed as a result of the call * @throws NullPointerException * if the specified element is null */ boolean add(Object i) { if (i == queue[counter]) { return false; } else if (i == null) throw new NullPointerException(); else { // Add Object to back of Queue queue[counter] = i; return true; } } /** * Removes all of the elements from this collection. The collection will be * empty after this method returns. */ void clear() { for (int i = 0; i < queue.length; i++) { queue[i] = null; } } /** * Returns true if this collection contains no elements. * * @return true if this collection contains no elements */ boolean isEmpty() { if (queue[0] == null) return true; else return false; } /** * Retrieves, but does not remove, the head of this queue, or returns null * if this queue is empty * * @return the head of this queue, or null if this queue is empty */ Object peek() { if (queue[counter] != null) return queue[counter]; else return null; } /** * Retrieves and removes the head of the queue. * * @return the head of this queue * @throws NoSuchElementException * if this queue is empty */ Object remove() { if (queue[0] != null) { Object temp = queue[0]; queue[0] = queue[1]; return temp; } else throw new NoSuchElementException(); } public class SetIterator implements Iterator<Object> { private int counter; public SetIterator() { this.counter = 0; } @Override public Object next() { counter++; if (queueSize == counter) return null; else if (queue[counter] != null) return (Object) queue[counter]; else throw new NoSuchElementException(); } @Override public boolean hasNext() { counter++; if (queueSize < counter) return false; else if (queue[counter] != null) return true; return false; } @Override public void remove() { throw new UnsupportedOperationException(); } } @Override public Iterator<Object> iterator() { return new SetIterator(); } public static void main(String args[]) { OrderedSet os; os.add("hello"); os.add(4); os.add("bye"); for (Object o : os) { System.out.println(o); } } } </code></pre>

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