1. /*
  2. * Copyright 2004 The Apache Software Foundation
  3. *
  4. * Licensed under the Apache License, Version 2.0 (the "License");
  5. * you may not use this file except in compliance with the License.
  6. * You may obtain a copy of the License at
  7. *
  8. * http://www.apache.org/licenses/LICENSE-2.0
  9. *
  10. * Unless required by applicable law or agreed to in writing, software
  11. * distributed under the License is distributed on an "AS IS" BASIS,
  12. * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  13. * See the License for the specific language governing permissions and
  14. * limitations under the License.
  15. */
  16. package org.apache.commons.collections.iterators;
  17. import java.util.Iterator;
  18. import org.apache.commons.collections.ResettableIterator;
  19. /**
  20. * Provides an implementation of an empty iterator.
  21. * <p>
  22. * This class provides an implementation of an empty iterator.
  23. * This class provides for binary compatability between Commons Collections
  24. * 2.1.1 and 3.1 due to issues with <code>IteratorUtils</code>.
  25. *
  26. * @since Commons Collections 2.1.1 and 3.1
  27. * @version $Revision: 1.1 $ $Date: 2004/05/22 09:46:39 $
  28. *
  29. * @author Stephen Colebourne
  30. */
  31. public class EmptyIterator extends AbstractEmptyIterator implements ResettableIterator {
  32. /**
  33. * Singleton instance of the iterator.
  34. * @since Commons Collections 3.1
  35. */
  36. public static final ResettableIterator RESETTABLE_INSTANCE = new EmptyIterator();
  37. /**
  38. * Singleton instance of the iterator.
  39. * @since Commons Collections 2.1.1 and 3.1
  40. */
  41. public static final Iterator INSTANCE = RESETTABLE_INSTANCE;
  42. /**
  43. * Constructor.
  44. */
  45. protected EmptyIterator() {
  46. super();
  47. }
  48. }