Movatterモバイル変換

Interface Iterator<E>

Type Parameters:
E - the type of elements returned by this iterator
All Known Subinterfaces:
EventIterator,ListIterator<E>,PrimitiveIterator<T,T_CONS>,PrimitiveIterator.OfDouble,PrimitiveIterator.OfInt,PrimitiveIterator.OfLong,XMLEventReader
All Known Implementing Classes:
BeanContextSupport.BCSIterator,EventReaderDelegate,Scanner
```
public interfaceIterator<E>
```
An iterator over a collection.Iterator takes the place ofEnumeration in the Java Collections Framework. Iterators differ from enumerations in two ways:
- Iterators allow the caller to remove elements from the underlying collection during the iteration with well-defined semantics.
- Method names have been improved.
This interface is a member of the Java Collections Framework.
API Note:
AnEnumeration can be converted into anIterator by using theEnumeration.asIterator() method.
Since:
1.2
See Also:
Collection,ListIterator,Iterable

Method Summary

All Methods Instance Methods Abstract Methods Default Methods
Modifier and Type	Method	Description
`default void`	`forEachRemaining(Consumer<? superE> action)`	Performs the given action for each remaining element until all elements have been processed or the action throws an exception.
`boolean`	`hasNext()`	Returns`true` if the iteration has more elements.
`E`	`next()`	Returns the next element in the iteration.
`default void`	`remove()`	Removes from the underlying collection the last element returned by this iterator (optional operation).

- Method Detail
  - hasNext
```
boolean hasNext()
```
    Returnstrue if the iteration has more elements. (In other words, returnstrue ifnext() would return an element rather than throwing an exception.)
    Returns:
    true if the iteration has more elements
  - next
```
E next()
```
    Returns the next element in the iteration.
    Returns:
    the next element in the iteration
    Throws:
    NoSuchElementException - if the iteration has no more elements
  - remove
```
default void remove()
```
    Removes from the underlying collection the last element returned by this iterator (optional operation). This method can be called only once per call tonext().
    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 theforEachRemaining method.
    Implementation Requirements:
    The default implementation throws an instance ofUnsupportedOperationException and performs no other action.
    Throws:
    UnsupportedOperationException - if theremove operation is not supported by this iterator
    IllegalStateException - if thenext method has not yet been called, or theremove method has already been called after the last call to thenext method
  - forEachRemaining
```
default void forEachRemaining(Consumer<? superE> action)
```
    Performs the given action for each remaining element until all elements have been processed or the action throws an exception. Actions are performed in the order of iteration, if that order is specified. Exceptions thrown by the action are relayed to the caller.
    The behavior of an iterator is unspecified if the action modifies the collection in any way (even by calling theremove method or other mutator methods ofIterator subtypes), unless an overriding class has specified a concurrent modification policy.
    Subsequent behavior of an iterator is unspecified if the action throws an exception.
    Implementation Requirements:
    The default implementation behaves as if:
    while (hasNext()) action.accept(next());
    Parameters:
    action - The action to be performed for each element
    Throws:
    NullPointerException - if the specified action is null
    Since:
    1.8

Movatterモバイル変換

Interface Iterator<E>

Method Summary

Method Detail

hasNext

next

remove

forEachRemaining