com.sun.labs.minion.indexer.entry
Class TermStatsEntry

java.lang.Object
  com.sun.labs.minion.indexer.entry.BaseEntry
      com.sun.labs.minion.indexer.entry.TermStatsEntry

All Implemented Interfaces:

Entry, IndexEntry, QueryEntry, java.lang.Comparable

public class TermStatsEntry
extends BaseEntry

An entry for the global term statistics dictionary. These entries will not have any postings.

Field Summary

Fields inherited from class com.sun.labs.minion.indexer.entry.BaseEntry

dict, id, name, postIn

Constructor Summary

TermStatsEntry()

TermStatsEntry(java.lang.String name)

Method Summary

void	add(Occurrence o) Adds an occurrence to this index entry.
void	append(QueryEntry qe, int start, int[] idMap) Appends the postings from another entry onto this one.
void	decodePostingsInfo(ReadableBuffer b, int pos) Decodes the postings information associated with this entry.
void	encodePostingsInfo(WriteableBuffer b) Encodes any information associated with the postings onto the given buffer.
Entry	getEntry() Gets a new entry that contains a copy of the data in this entry.
Entry	getEntry(java.lang.Object name) Gets a new entry with the given name.
int	getMaxFDT() Gets the maximum document term frequency from this entry.
int	getN() Gets the number of postings associated with this entry.
int	getNumChannels() Returns the number of channels needed to store or retrieve the postings for this entry type.
TermStatsImpl	getTermStats()
long	getTotalOccurrences() Gets the total number of occurrences associated with this entry.
boolean	hasFieldInformation() Indicates whether the postings associated with this entry have field information.
boolean	hasPositionInformation() Indicates whether the postings associated with this entry have position information.
PostingsIterator	iterator(PostingsIteratorFeatures features) Gets an iterator that will iterate through the postings associated with this entry.
void	readPostings() Reads the postings data for this entry.
void	setTermStats(TermStatsImpl ts)
boolean	writePostings(PostingsOutput[] out, int[] idMap) Writes the postings associated with this entry to some or all of the given channels.

Methods inherited from class com.sun.labs.minion.indexer.entry.BaseEntry

compareTo, getID, getName, getPartition, setDictionary, setID, setName, setPostingsInput, toString

Methods inherited from class java.lang.Object

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

Constructor Detail

TermStatsEntry

public TermStatsEntry()

TermStatsEntry

public TermStatsEntry(java.lang.String name)

Method Detail

setTermStats

public void setTermStats(TermStatsImpl ts)

getTermStats

public TermStatsImpl getTermStats()

add

public void add(Occurrence o)

Description copied from interface: IndexEntry

Adds an occurrence to this index entry.

Parameters:

o - The occurrence to add.

writePostings

public boolean writePostings(PostingsOutput[] out,
                             int[] idMap)
                      throws java.io.IOException

Description copied from interface: IndexEntry

Writes the postings associated with this entry to some or all of the given channels.

Parameters:

out - The outputs to which we will write the postings.

idMap - A map from the IDs currently used in the postings to the IDs that should be used when the postings are written to disk. This may be null, in which case no remapping will occur.

Returns:

true if postings were written, false otherwise

Throws:

java.io.IOException - if there is any error writing the postings.

append

public void append(QueryEntry qe,
                   int start,
                   int[] idMap)

Description copied from interface: IndexEntry

Appends the postings from another entry onto this one. This is used when merging dictionaries.

Parameters:

qe - The entry that we want to append onto this one.

start - The new starting ID for the partition that the entry was drawn from.

idMap - A map from old IDs in the given postings to new IDs with gaps removed for deleted data. If this is null, then there are no deleted documents.

encodePostingsInfo

public void encodePostingsInfo(WriteableBuffer b)

Description copied from interface: IndexEntry

Encodes any information associated with the postings onto the given buffer.

Parameters:

b - The buffer onto which the postings information should be encoded. The buffer will be positioned to the correct spot for the encoding.

getEntry

public Entry getEntry(java.lang.Object name)

Description copied from interface: Entry

Gets a new entry with the given name.

Parameters:

name - the name that we want to give the entry.

Returns:

a new entry.

getEntry

public Entry getEntry()

Description copied from interface: Entry

Gets a new entry that contains a copy of the data in this entry.

Returns:

a new entry.

getN

public int getN()

Description copied from interface: Entry

Gets the number of postings associated with this entry. This can be used to sort entries by their frequency during query operations.

Returns:

The number of postings associated with this entry.

getTotalOccurrences

public long getTotalOccurrences()

Description copied from interface: Entry

Gets the total number of occurrences associated with this entry. This is useful when a single postings entry may comprise multiple occurrences.

At the moment, this is only really useful for entries from the main dictionary for a partition.

Returns:

The total number of occurrences associated with this entry.

getMaxFDT

public int getMaxFDT()

Description copied from interface: Entry

Gets the maximum document term frequency from this entry. For all IDs asssociated with this entry, this is the maximum frequency across all the IDs.

getNumChannels

public int getNumChannels()

Description copied from interface: Entry

Returns the number of channels needed to store or retrieve the postings for this entry type.

decodePostingsInfo

public void decodePostingsInfo(ReadableBuffer b,
                               int pos)

Description copied from interface: QueryEntry

Decodes the postings information associated with this entry.

Parameters:

b - The buffer containing the encoded postings information.

pos - The position in b where the postings information can be found.

readPostings

public void readPostings()
                  throws java.io.IOException

Description copied from interface: QueryEntry

Reads the postings data for this entry. This method must load all available postings information, since this will be used at dictionary merge time to append postings from one entry onto another.

Throws:

java.io.IOException - if there is any error reading the postings.

hasPositionInformation

public boolean hasPositionInformation()

Description copied from interface: QueryEntry

Indicates whether the postings associated with this entry have position information.

hasFieldInformation

public boolean hasFieldInformation()

Description copied from interface: QueryEntry

Indicates whether the postings associated with this entry have field information.

iterator

public PostingsIterator iterator(PostingsIteratorFeatures features)

Description copied from interface: QueryEntry

Gets an iterator that will iterate through the postings associated with this entry.

Parameters:

features - A set of features that the iterator must support.

Returns:

An iterator for the postings.