java.util
Interface Iterator

All Known Subinterfaces:

ListIterator

public interface Iterator

An object which iterates over a collection. An Iterator is used to return the items once only, in sequence, by successive calls to the next method. It is also possible to remove elements from the underlying collection by using the optional remove method. Iterator is intended as a replacement for the Enumeration interface of previous versions of Java, which did not have the remove method and had less conveniently named methods.

Since:

1.2

See Also:

Collection, ListIterator, Enumeration

Method Summary

boolean	hasNext() Tests whether there are elements remaining in the collection.
Object	next() Obtain the next element in the collection.
void	remove() Remove from the underlying collection the last element returned by next (optional operation).

Method Detail

hasNext

boolean hasNext()

Tests whether there are elements remaining in the collection. In other words, calling next() will not throw an exception.

Returns:

true if there is at least one more element in the collection

next

Object next()

Obtain the next element in the collection.

Returns:

the next element in the collection

Throws:

NoSuchElementException - if there are no more elements

remove

void remove()

Remove from the underlying collection the last element returned by next (optional operation). This method can be called only once after each call to next(). It does not affect what will be returned by subsequent calls to next.

Throws:

IllegalStateException - if next has not yet been called or remove has already been called since the last call to next.

UnsupportedOperationException - if this Iterator does not support the remove operation.