Package org.apache.commons.collections4.iterators

# Class BoundedIterator<E>

java.lang.Object
org.apache.commons.collections4.iterators.BoundedIterator<E>

Type Parameters:
  `E` - the type of elements returned by this iterator.

All Implemented Interfaces:
  `Iterator<E>`

public class BoundedIterator<E> extends Object implements Iterator<E>
Decorates another iterator to return elements in a specific range.

The decorated iterator is bounded in the range [offset, offset+max). The `offset` corresponds to the position of the first element to be returned from the decorated iterator, and `max` is the maximum number of elements to be returned at most.

In case an offset parameter other than 0 is provided, the decorated iterator is immediately advanced to this position, skipping all elements before that position.

Since:
  4.1

- ## Constructor Summary

  Constructors
  Constructor
  Description
  `BoundedIterator(Iterator<? extends E> iterator, long offset, long max)`
  Decorates the specified iterator to return at most the given number of elements, skipping all elements until the iterator reaches the position at `offset`.

- ## Method Summary

  Modifier and Type
  Method
  Description
  `boolean`
  `hasNext()`
  `E`
  `next()`
  `void`
  `remove()`

  ### Methods inherited from class java.lang.Object

  `clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait`

  ### Methods inherited from interface java.util.Iterator

  `forEachRemaining`

- ## Constructor Details

  - ### BoundedIterator

    public BoundedIterator(Iterator<? extends E> iterator, long offset, long max)
    Decorates the specified iterator to return at most the given number of elements, skipping all elements until the iterator reaches the position at `offset`.

    The iterator is immediately advanced until it reaches the position at `offset`, incurring O(n) time.

    Parameters:
      `iterator` - the iterator to be decorated
      `offset` - the index of the first element of the decorated iterator to return
      `max` - the maximum number of elements of the decorated iterator to return
    Throws:
      `NullPointerException` - if iterator is null
      `IllegalArgumentException` - if either offset or max is negative

- ## Method Details

  - ### hasNext

    public boolean hasNext()
    Specified by:
      `hasNext` in interface `Iterator<E>`

  - ### next

    public E next()
    Specified by:
      `next` in interface `Iterator<E>`

  - ### remove

    public void remove()

    In case an offset other than 0 was specified, the underlying iterator will be advanced to this position upon creation. A call to `remove()` will still result in an `IllegalStateException` if no explicit call to `next()` has been made prior to calling `remove()`.

    Specified by:
      `remove` in interface `Iterator<E>`