Implement Iterator for Array | N00tc0d3r

Implement Iterator for Array | N00tc0d3r
public class MyIterable<E> implements Iterable<E> {
   E[] elems;
   int nElems;

   /**
    * Constructor.
    */
   public MyIterable(E[] data) {
     this.elems = data;
     nElems = data.length;
   }

   /**
    * Returns an iterator over a set of elements of type E.
    */
   public Iterator<E> iterator() {
     return new MyIterator<E>();
   }
 
   private class MyIterator<E> implements Iterator<E> {
     int nextElem = 0;
     boolean hasRemoved = true;
 
     /**
      * Returns true if the iteration has more elements.
      * In other words, returns true if next() would return an element
      * rather than throwing an exception.
      */
     public boolean hasNext() {
       return nextElem < nElems;
     }
 
     /**
      * Returns the next element in the iteration.
      *  
      * Throws: java.util.NoSuchElementException if the iteration has no more elements
      */
     public E next() {
       if (!hasNext()) {
         throw new NoSuchElementException("No more elements");
       }
 
       E e = elems[nextElem];
       ++nextElem;
       hasRemoved = false;
       return e;
     }
 
     /**
      * Removes from the underlying collection the last element returned by this iterator.
      * This method can be called only once per call to next(). The behavior of an iterator
      * is unspecified if the underlying collection is modified while the iteration is in
      * progress in any way other than by calling this method.
      *  
      * Throws: java.lang.IllegalStateException if the next method has not yet been called,
      * or the remove method has already been called after the last call to the next method.
      */
     public void remove() {
       if (hasRemoved) {
         throw new IllegalStateException(
           "The remove method can only be called once and after the next method.");
       }
 
       if (nextElem < nElems - 1) {
         System.arraycopy(elems, nextElem+1, elems, nextElem, nElems-nextElem-1);
       }
       --nElems;
       hasRemoved = true;
     }
   }
 }
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