org.apache.lucene.util
Class MergedIterator<T extends Comparable<T>>

java.lang.Object
  org.apache.lucene.util.MergedIterator<T>

All Implemented Interfaces:

Iterator<T>

public final class MergedIterator<T extends Comparable<T>>
extends Object
implements Iterator<T>

Provides a merged sorted view from several sorted iterators.

If built with removeDuplicates set to true and an element appears in multiple iterators then it is deduplicated, that is this iterator returns the sorted union of elements.

If built with removeDuplicates set to false then all elements in all iterators are returned.

Caveats:

• The behavior is undefined if the iterators are not actually sorted.
• Null elements are unsupported.
• If removeDuplicates is set to true and if a single iterator contains duplicates then they will not be deduplicated.
• When elements are deduplicated it is not defined which one is returned.
• If removeDuplicates is set to false then the order in which duplicates are returned isn't defined.

NOTE: This API is for internal purposes only and might change in incompatible ways in the next release.

Constructor Summary

MergedIterator(boolean removeDuplicates, Iterator<T>... iterators)

MergedIterator(Iterator<T>... iterators)

Method Summary

boolean	hasNext()
T	next()
void	remove()

Methods inherited from class java.lang.Object

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

Constructor Detail

MergedIterator

public MergedIterator(Iterator<T>... iterators)

MergedIterator

public MergedIterator(boolean removeDuplicates,
                      Iterator<T>... iterators)

Method Detail

hasNext

public boolean hasNext()

Specified by:

hasNext in interface Iterator<T extends Comparable<T>>

next

public T next()

Specified by:

next in interface Iterator<T extends Comparable<T>>

remove

public void remove()

Specified by:

remove in interface Iterator<T extends Comparable<T>>