java.util.Iterator<E> |
Known Indirect Subclasses |
An Iterator
is used to sequence over a collection of objects.
Conceptually, an iterator is always positioned between two elements of a
collection. A fresh iterator is always positioned in front of the first
element.
If a collection has been changed since its creation, methods next
and
hasNext()
may throw a ConcurrentModificationException
.
Iterators with this behavior are called fail-fast iterators.
Public Methods | |||||||||||
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Returns whether there are more elements to iterate, i.e.
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Returns the next object in the iteration, i.e.
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Removes the last object returned by
next from the collection. |
Returns whether there are more elements to iterate, i.e. whether the iterator is positioned in front of an element.
true
if there are more elements, false
otherwise.Returns the next object in the iteration, i.e. returns the element in front of the iterator and advances the iterator by one position.
NoSuchElementException | if there are no more elements. |
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Removes the last object returned by next
from the collection.
This method can only be called once after next
was called.
UnsupportedOperationException | if removing is not supported by the collection being iterated. |
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IllegalStateException | if next has not been called, or remove has
already been called after the last call to next .
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