package com.atlassian.plugin.util.collect;
   
   import static com.atlassian.plugin.util.Assertions.notNull;
   
   import java.util.Iterator;
   
   /**
    * {@link Iterator} implementation that decorates another {@link Iterator} who
    * contains values of type I and uses a {@link Function} that converts that I 
   * into a V.
   * <p>
   * This implementation is unmodifiable.
   *
   * @param <I> the value in the underlying iterator
   * @param <E> the value it is converted to
   */
  class TransformingIterator<I, E> implements Iterator<E>
  {
      private final Iterator<? extends I> iterator;
      private final Function<I, E> decorator;
  
      TransformingIterator(final Iterator<? extends I> iterator, final Function<I, E> decorator)
      {
          this.iterator = notNull("iterator", iterator);
          this.decorator = notNull("decorator", decorator);
      }
  
      public boolean hasNext()
      {
          return iterator.hasNext();
      }
  
      public E next()
      {
          return decorator.get(iterator.next());
      }
  
      public void remove()
      {
          iterator.remove();
      }
  }