E- the type of elements returned by this iterator
public interface Iterator<E>
Iteratortakes the place of
Enumerationin the Java Collections Framework. Iterators differ from enumerations in two ways:
This interface is a member of the Java Collections Framework.
|Modifier and Type||Method||Description|
Performs the given action for each remaining element until all elements have been processed or the action throws an exception.
Returns the next element in the iteration.
Removes from the underlying collection the last element returned by this iterator (optional operation).
trueif the iteration has more elements. (In other words, returns
next()would return an element rather than throwing an exception.)
trueif the iteration has more elements
NoSuchElementException- if the iteration has no more elements
default void remove()
The behavior of an iterator is unspecified if the underlying collection is modified while the iteration is in progress in any way other than by calling this method, unless an overriding class has specified a concurrent modification policy.
The behavior of an iterator is unspecified if this method is called
after a call to the
UnsupportedOperationExceptionand performs no other action.
UnsupportedOperationException- if the
removeoperation is not supported by this iterator
IllegalStateException- if the
nextmethod has not yet been called, or the
removemethod has already been called after the last call to the
The behavior of an iterator is unspecified if the action modifies the
collection in any way (even by calling the
unless an overriding class has specified a concurrent modification policy.
Subsequent behavior of an iterator is unspecified if the action throws an exception.
The default implementation behaves as if:
while (hasNext()) action.accept(next());
action- The action to be performed for each element
NullPointerException- if the specified action is null
Submit a bug or feature
For further API reference and developer documentation, see Java SE Documentation. That documentation contains more detailed, developer-targeted descriptions, with conceptual overviews, definitions of terms, workarounds, and working code examples.
Copyright © 1993, 2017, Oracle and/or its affiliates. 500 Oracle Parkway
Redwood Shores, CA 94065 USA. All rights reserved.