org.apache.accumulo.core.iterators
Class MultiIterator

java.lang.Object
  org.apache.accumulo.core.iterators.HeapIterator
      org.apache.accumulo.core.iterators.MultiIterator

All Implemented Interfaces:

SortedKeyValueIterator<Key,Value>

public class MultiIterator
extends HeapIterator

An iterator capable of iterating over other iterators in sorted order.

Constructor Summary

MultiIterator(java.util.List<SortedKeyValueIterator<Key,Value>> readers, boolean init)

MultiIterator(java.util.List<SortedKeyValueIterator<Key,Value>> iters2, KeyExtent extent)

MultiIterator(java.util.List<SortedKeyValueIterator<Key,Value>> iters, Range seekFence)

Method Summary

MultiIterator	deepCopy(IteratorEnvironment env) Creates a deep copy of this iterator as though seek had not yet been called.
void	init(SortedKeyValueIterator<Key,Value> source, java.util.Map<java.lang.String,java.lang.String> options, IteratorEnvironment env) Initializes the iterator.
void	seek(Range range, java.util.Collection<ByteSequence> columnFamilies, boolean inclusive) An iterator must seek to the first key in the range taking inclusiveness into account.

Methods inherited from class org.apache.accumulo.core.iterators.HeapIterator

addSource, clear, createHeap, getTopKey, getTopValue, hasTop, next

Methods inherited from class java.lang.Object

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

Constructor Detail

MultiIterator

public MultiIterator(java.util.List<SortedKeyValueIterator<Key,Value>> iters,
                     Range seekFence)

MultiIterator

public MultiIterator(java.util.List<SortedKeyValueIterator<Key,Value>> iters2,
                     KeyExtent extent)

MultiIterator

public MultiIterator(java.util.List<SortedKeyValueIterator<Key,Value>> readers,
                     boolean init)

Method Detail

deepCopy

public MultiIterator deepCopy(IteratorEnvironment env)

Description copied from interface: SortedKeyValueIterator

Creates a deep copy of this iterator as though seek had not yet been called. init should be called on an iterator before deepCopy is called. init should not need to be called on the copy that is returned by deepCopy; that is, when necessary init should be called in the deepCopy method on the iterator it returns. The behavior is unspecified if init is called after deepCopy either on the original or the copy.

Parameters:

env - IteratorEnvironment environment in which iterator is being run.

Returns:

SortedKeyValueIterator a copy of this iterator (with the same source and settings).

seek

public void seek(Range range,
                 java.util.Collection<ByteSequence> columnFamilies,
                 boolean inclusive)
          throws java.io.IOException

Description copied from interface: SortedKeyValueIterator

An iterator must seek to the first key in the range taking inclusiveness into account. However, an iterator does not have to stop at the end of the range. The whole range is provided so that iterators can make optimizations.

Parameters:

range - Range of keys to iterate over.

columnFamilies - Collection of column families to include or exclude.

inclusive - boolean that indicates whether to include (true) or exclude (false) column families.

Throws:

java.io.IOException - if an I/O error occurs.

init

public void init(SortedKeyValueIterator<Key,Value> source,
                 java.util.Map<java.lang.String,java.lang.String> options,
                 IteratorEnvironment env)
          throws java.io.IOException

Description copied from interface: SortedKeyValueIterator

Initializes the iterator. Data should not be read from the source in this method.

Parameters:

source - SortedKeyValueIterator source to read data from.

options - Map map of string option names to option values.

env - IteratorEnvironment environment in which iterator is being run.

Throws:

java.io.IOException - unused.