org.apache.accumulo.core.iterators
Class AggregatingIterator

java.lang.Object
  extended by org.apache.accumulo.core.iterators.AggregatingIterator
All Implemented Interfaces:
OptionDescriber, SortedKeyValueIterator<Key,Value>

Deprecated. since 1.4, replaced by Combiner

public class AggregatingIterator
extends Object
implements SortedKeyValueIterator<Key,Value>, OptionDescriber

This iterator wraps another iterator. It automatically aggregates.


Nested Class Summary
 
Nested classes/interfaces inherited from interface org.apache.accumulo.core.iterators.OptionDescriber
OptionDescriber.IteratorOptions
 
Constructor Summary
AggregatingIterator()
          Deprecated.  
AggregatingIterator(SortedKeyValueIterator<Key,Value> iterator, ColumnToClassMapping<Aggregator> aggregators)
          Deprecated.  
 
Method Summary
 AggregatingIterator deepCopy(IteratorEnvironment env)
          Deprecated. Creates a deep copy of this iterator as though seek had not yet been called.
 OptionDescriber.IteratorOptions describeOptions()
          Deprecated. Gets an iterator options object that contains information needed to configure this iterator.
 Key getTopKey()
          Deprecated. Returns top key.
 Value getTopValue()
          Deprecated. Returns top value.
 boolean hasTop()
          Deprecated. Returns true if the iterator has more elements.
 void init(SortedKeyValueIterator<Key,Value> source, Map<String,String> options, IteratorEnvironment env)
          Deprecated. Initializes the iterator.
 void next()
          Deprecated. Advances to the next K,V pair.
 void seek(Range range, Collection<ByteSequence> columnFamilies, boolean inclusive)
          Deprecated. Seeks to the first key in the Range, restricting the resulting K,V pairs to those with the specified columns.
 boolean validateOptions(Map<String,String> options)
          Deprecated. Check to see if an options map contains all options required by an iterator and that the option values are in the expected formats.
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Constructor Detail

AggregatingIterator

public AggregatingIterator()
Deprecated. 

AggregatingIterator

public AggregatingIterator(SortedKeyValueIterator<Key,Value> iterator,
                           ColumnToClassMapping<Aggregator> aggregators)
                    throws IOException
Deprecated. 
Throws:
IOException
Method Detail

deepCopy

public AggregatingIterator deepCopy(IteratorEnvironment env)
Deprecated. 
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>
Parameters:
env - IteratorEnvironment environment in which iterator is being run.
Returns:
SortedKeyValueIterator a copy of this iterator (with the same source and settings).

getTopKey

public Key getTopKey()
Deprecated. 
Description copied from interface: SortedKeyValueIterator
Returns top key. Can be called 0 or more times without affecting behavior of next() or hasTop(). Note that in minor compaction scope and in non-full major compaction scopes the iterator may see deletion entries. These entries should be preserved by all iterators except ones that are strictly scan-time iterators that will never be configured for the minc or majc scopes. Deletion entries are only removed during full major compactions.

Specified by:
getTopKey in interface SortedKeyValueIterator<Key,Value>
Returns:
K

getTopValue

public Value getTopValue()
Deprecated. 
Description copied from interface: SortedKeyValueIterator
Returns top value. Can be called 0 or more times without affecting behavior of next() or hasTop().

Specified by:
getTopValue in interface SortedKeyValueIterator<Key,Value>
Returns:
V

hasTop

public boolean hasTop()
Deprecated. 
Description copied from interface: SortedKeyValueIterator
Returns true if the iterator has more elements.

Specified by:
hasTop in interface SortedKeyValueIterator<Key,Value>
Returns:
true if the iterator has more elements.

next

public void next()
          throws IOException
Deprecated. 
Description copied from interface: SortedKeyValueIterator
Advances to the next K,V pair. Note that in minor compaction scope and in non-full major compaction scopes the iterator may see deletion entries. These entries should be preserved by all iterators except ones that are strictly scan-time iterators that will never be configured for the minc or majc scopes. Deletion entries are only removed during full major compactions.

Specified by:
next in interface SortedKeyValueIterator<Key,Value>
Throws:
IOException - if an I/O error occurs.

seek

public void seek(Range range,
                 Collection<ByteSequence> columnFamilies,
                 boolean inclusive)
          throws IOException
Deprecated. 
Description copied from interface: SortedKeyValueIterator
Seeks to the first key in the Range, restricting the resulting K,V pairs to those with the specified columns. An iterator does not have to stop at the end of the range. The whole range is provided so that iterators can make optimizations. Seek may be called multiple times with different parameters after SortedKeyValueIterator.init(org.apache.accumulo.core.iterators.SortedKeyValueIterator, java.util.Map, org.apache.accumulo.core.iterators.IteratorEnvironment) is called. Iterators that examine groups of adjacent key/value pairs (e.g. rows) to determine their top key and value should be sure that they properly handle a seek to a key in the middle of such a group (e.g. the middle of a row). Even if the client always seeks to a range containing an entire group (a,c), the tablet server could send back a batch of entries corresponding to (a,b], then reseek the iterator to range (b,c) when the scan is continued. columnFamilies is used, at the lowest level, to determine which data blocks inside of an RFile need to be opened for this iterator. This set of data blocks is also the set of locality groups defined for the given table. If no columnFamilies are provided, the data blocks for all locality groups inside of the correct RFile will be opened and seeked in an attempt to find the correct start key, irregardless of the startKey in the range. In an Accumulo instance in which multiple locality groups exist for a table, it is important to ensure that columnFamilies is properly set to the minimum required column families to ensure that data from separate locality groups is not inadvertently read.

Specified by:
seek in interface SortedKeyValueIterator<Key,Value>
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:
IOException - if an I/O error occurs.

init

public void init(SortedKeyValueIterator<Key,Value> source,
                 Map<String,String> options,
                 IteratorEnvironment env)
          throws IOException
Deprecated. 
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>
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:
IOException - unused.

describeOptions

public OptionDescriber.IteratorOptions describeOptions()
Deprecated. 
Description copied from interface: OptionDescriber
Gets an iterator options object that contains information needed to configure this iterator. This object will be used by the accumulo shell to prompt the user to input the appropriate information.

Specified by:
describeOptions in interface OptionDescriber
Returns:
an iterator options object

validateOptions

public boolean validateOptions(Map<String,String> options)
Deprecated. 
Description copied from interface: OptionDescriber
Check to see if an options map contains all options required by an iterator and that the option values are in the expected formats.

Specified by:
validateOptions in interface OptionDescriber
Parameters:
options - a map of option names to option values
Returns:
true if options are valid, false otherwise


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