Module org.jhotdraw8.collection
Package org.jhotdraw8.collection.enumerator

Interface BareEnumerator<E>

Type Parameters:
E - the element type
All Known Subinterfaces:
Enumerator<E>, Enumerator.OfDouble, Enumerator.OfInt, Enumerator.OfLong
All Known Implementing Classes:
AbstractDoubleEnumerator, AbstractEnumerator, AbstractIntEnumerator, AbstractLongEnumerator, EmptyEnumerator, IntArrayEnumerator, IntCharArrayEnumerator, IntRangeEnumerator, IntUShortArrayEnumerator, IteratorEnumeratorFacade, SingletonSpliterator, SpliteratorEnumeratorFacade
public interface BareEnumerator<E>
Bare (minimalistic) interface for enumerating elements of a collection.

The protocol for accessing elements via a BareEnumerator imposes smaller per-element overhead than Iterator, and avoids the inherent race involved in having separate methods for hasNext() and next().

This interface is typically not used, it is more convenient to use the Enumerator interface instead, which extends from the Spliterator interface.

Usage: 

 for (BareEnumerator<E> i = ...; i.moveNext(); ) {
   var e = i.current();
   ...
 }
Author:
Werner Randelshofer

  • Method Summary

    Modifier and Type
    Method
    Description
    E
    current()
    Gets the element in the collection at the current position of the enumerator.
    boolean
    moveNext()
    Advances the enumerator to the next element of the collection.

  • Method Details

    • moveNext

      boolean moveNext()
      Advances the enumerator to the next element of the collection.
      Returns:
      true if the enumerator was successfully advanced to the next element; false if the enumerator has passed the end of the collection.

    • current

      E current()
      Gets the element in the collection at the current position of the enumerator.

      Current is undefined under any of the following conditions:

      • The enumerator is positioned before the first element in the collection. Immediately after the enumerator is created moveNext() must be called to advance the enumerator to the first element of the collection before reading the value of Current.
      • The last call to moveNext() returned false, which indicates the end of the collection.
      • The enumerator is invalidated due to changes made in the collection, such as adding, modifying, or deleting elements.
      Current returns the same object until MoveNext is called.MoveNext sets Current to the next element.
      Returns:
      current