org.apache.accumulo.core.iterators
Class VersioningIterator

java.lang.Object
  org.apache.accumulo.core.iterators.WrappingIterator
      org.apache.accumulo.core.iterators.VersioningIterator

All Implemented Interfaces:

OptionDescriber, SortedKeyValueIterator<Key,Value>

public class VersioningIterator
extends WrappingIterator
implements OptionDescriber

Nested Class Summary

Nested classes/interfaces inherited from interface org.apache.accumulo.core.iterators.OptionDescriber

OptionDescriber.IteratorOptions

Field Summary

boolean

lazyReset

Constructor Summary

VersioningIterator()

VersioningIterator(SortedKeyValueIterator<Key,Value> iterator, int maxVersions)

Method Summary

VersioningIterator	deepCopy(IteratorEnvironment env) Creates a deep copy of this iterator as though seek had not yet been called.
OptionDescriber.IteratorOptions	describeOptions()
boolean	hasTop() Returns true if the iterator has more elements.
void	init(SortedKeyValueIterator<Key,Value> source, java.util.Map<java.lang.String,java.lang.String> options, IteratorEnvironment env) Initializes the iterator.
void	next() Advances to the next K,V pair.
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.
boolean	validateOptions(java.util.Map<java.lang.String,java.lang.String> options)

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

getSource, getTopKey, getTopValue, setSource

Methods inherited from class java.lang.Object

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

Field Detail

lazyReset

public boolean lazyReset

Constructor Detail

VersioningIterator

public VersioningIterator()

VersioningIterator

public VersioningIterator(SortedKeyValueIterator<Key,Value> iterator,
                          int maxVersions)

Method Detail

deepCopy

public VersioningIterator 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.

Specified by:

deepCopy in interface SortedKeyValueIterator<Key,Value>

Specified by:

deepCopy in class WrappingIterator

Parameters:

env - IteratorEnvironment environment in which iterator is being run.

Returns:

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

next

public void next()
          throws java.io.IOException

Description copied from interface: SortedKeyValueIterator

Advances to the next K,V pair.

Specified by:

next in interface SortedKeyValueIterator<Key,Value>

Overrides:

next in class WrappingIterator

Throws:

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

hasTop

public boolean hasTop()

Description copied from interface: SortedKeyValueIterator

Returns true if the iterator has more elements.

Specified by:

hasTop in interface SortedKeyValueIterator<Key,Value>

Overrides:

hasTop in class WrappingIterator

Returns:

true if the iterator has more elements.

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.

Specified by:

seek in interface SortedKeyValueIterator<Key,Value>

Overrides:

seek in class WrappingIterator

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.

Specified by:

init in interface SortedKeyValueIterator<Key,Value>

Overrides:

init in class WrappingIterator

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.

describeOptions

public OptionDescriber.IteratorOptions describeOptions()

Specified by:

describeOptions in interface OptionDescriber

validateOptions

public boolean validateOptions(java.util.Map<java.lang.String,java.lang.String> options)

Specified by:

validateOptions in interface OptionDescriber