Package com.google.common.collect

Interface PeekingIterator<E>

  • All Superinterfaces:
    java.util.Iterator<E>
    @GwtCompatible
public interface PeekingIterator<E>
extends java.util.Iterator<E>
    An iterator that supports a one-element lookahead while iterating.

    See the Guava User Guide article on PeekingIterator.

    Since:
    2.0 (imported from Google Collections Library)

    • Method Summary

      All Methods Instance Methods Abstract Methods 
      Modifier and Type Method Description
      E next()
      E peek()
      Returns the next element in the iteration, without advancing the iteration.
      void remove()

      • Methods inherited from interface java.util.Iterator

        forEachRemaining, hasNext

    • Method Detail

      • peek

        E peek()
        Returns the next element in the iteration, without advancing the iteration.

        Calls to peek() should not change the state of the iteration, except that it may prevent removal of the most recent element via remove().

        Throws:
        java.util.NoSuchElementException - if the iteration has no more elements according to Iterator.hasNext()

      • next

        E next()

        The objects returned by consecutive calls to peek() then next() are guaranteed to be equal to each other.

        Specified by:
        next in interface java.util.Iterator<E>

      • remove

        void remove()

        Implementations may or may not support removal when a call to peek() has occurred since the most recent call to next().

        Specified by:
        remove in interface java.util.Iterator<E>
        Throws:
        java.lang.IllegalStateException - if there has been a call to peek() since the most recent call to next() and this implementation does not support this sequence of calls (optional)