Package com.globalmentor.collections.iterators

Class ListIteratorDecorator<E>

java.lang.Object
com.globalmentor.collections.iterators.AbstractIteratorDecorator<E>
com.globalmentor.collections.iterators.IteratorDecorator<E>
com.globalmentor.collections.iterators.ListIteratorDecorator<E>
All Implemented Interfaces:
Enumeration<E>, Iterator<E>, ListIterator<E>
Direct Known Subclasses:
AbstractConverterList.ConverterListIterator
public class ListIteratorDecorator<E> extends IteratorDecorator<E> implements ListIterator<E>
A list iterator that wraps an existing list iterator, providing access through the ListIterator interface.
Author:
Garret Wilson

  • Field Details

    • listIterator

      protected final ListIterator<E> listIterator
      The list iterator this class decorates.

  • Constructor Details

    • ListIteratorDecorator

      public ListIteratorDecorator(ListIterator<E> listIterator)
      List iterator constructor.
      Parameters:
      listIterator - The list iterator this list iterator should decorate.
      Throws:
      NullPointerException - if the given iterator is null.

  • Method Details

    • hasPrevious

      public boolean hasPrevious()
      Returns true if this list iterator has more elements when traversing the list in the reverse direction. (In other words, returns true if previous would return an element rather than throwing an exception.)
      Specified by:
      hasPrevious in interface ListIterator<E>
      Returns:
      true if the list iterator has more elements when traversing the list in the reverse direction.

    • previous

      public E previous()
      Returns the previous element in the list. This method may be called repeatedly to iterate through the list backwards, or intermixed with calls to next to go back and forth. (Note that alternating calls to next and previous will return the same element repeatedly.)
      Specified by:
      previous in interface ListIterator<E>
      Returns:
      the previous element in the list.
      Throws:
      NoSuchElementException - if the iteration has no previous element.

    • nextIndex

      public int nextIndex()
      Returns the index of the element that would be returned by a subsequent call to next. (Returns list size if the list iterator is at the end of the list.)
      Specified by:
      nextIndex in interface ListIterator<E>
      Returns:
      the index of the element that would be returned by a subsequent call to next, or list size if list iterator is at end of list.

    • previousIndex

      public int previousIndex()
      Returns the index of the element that would be returned by a subsequent call to previous. (Returns -1 if the list iterator is at the beginning of the list.)
      Specified by:
      previousIndex in interface ListIterator<E>
      Returns:
      the index of the element that would be returned by a subsequent call to previous, or -1 if list iterator is at beginning of list.

    • set

      public void set(E o)
      Replaces the last element returned by next or previous with the specified element (optional operation). This call can be made only if neither ListIterator.remove nor ListIterator.add have been called after the last call to next or previous.
      Specified by:
      set in interface ListIterator<E>
      Parameters:
      o - the element with which to replace the last element returned by next or previous.
      Throws:
      UnsupportedOperationException - if the set operation is not supported by this list iterator.
      ClassCastException - if the class of the specified element prevents it from being added to this list.
      IllegalArgumentException - if some aspect of the specified element prevents it from being added to this list.
      IllegalStateException - if neither next nor previous have been called, or remove or add have been called after the last call to next or previous.

    • add

      public void add(E o)
      Inserts the specified element into the list (optional operation). The element is inserted immediately before the next element that would be returned by next, if any, and after the next element that would be returned by previous, if any. (If the list contains no elements, the new element becomes the sole element on the list.) The new element is inserted before the implicit cursor: a subsequent call to next would be unaffected, and a subsequent call to previous would return the new element. (This call increases by one the value that would be returned by a call to nextIndex or previousIndex.)
      Specified by:
      add in interface ListIterator<E>
      Parameters:
      o - the element to insert.
      Throws:
      UnsupportedOperationException - if the add method is not supported by this list iterator.
      ClassCastException - if the class of the specified element prevents it from being added to this list.
      IllegalArgumentException - if some aspect of this element prevents it from being added to this list.