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

java.lang.Object
  com.sun.labs.minion.indexer.entry.BaseEntry
      com.sun.labs.minion.indexer.entry.SinglePostingsEntry
          com.sun.labs.minion.indexer.entry.DFOEntry

All Implemented Interfaces:

Entry, IndexEntry, QueryEntry, java.lang.Comparable

public class DFOEntry
extends SinglePostingsEntry

Field Summary

protected int	fnpSize The size of the data including fields and positions data.
protected int	maxfdt The maximum frequency of the term across the documents in the postings list.
protected long	to The total number of occurrences in the postings list associated with this entry.

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

logTag, n, offset, p, size, tsize

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

dict, id, name, postIn

Constructor Summary

DFOEntry()

DFOEntry(java.lang.Object name)

Method Summary

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.
IndexEntry	getInstance(java.lang.Object name) Gets a new instance of the implementing class.
int	getMaxFDT() Gets the maximum frequency in the postings associated with this entry.
protected Postings	getPostings() Gets the appropriate postings type for the class.
protected Postings	getPostings(ReadableBuffer input) Reads the postings for this class, returning a set of postings useful at query time.
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 a set of postings associated with this entry.
void	readPostings() Reads the postings data for this entry.
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.SinglePostingsEntry

add, append, copyData, getN, getNumChannels

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

Field Detail

to

protected long to

The total number of occurrences in the postings list associated with this entry.

maxfdt

protected int maxfdt

The maximum frequency of the term across the documents in the postings list.

fnpSize

protected int fnpSize

The size of the data including fields and positions data.

Constructor Detail

DFOEntry

public DFOEntry()

DFOEntry

public DFOEntry(java.lang.Object name)

Method Detail

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()

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

Specified by:

getEntry in interface Entry

Overrides:

getEntry in class SinglePostingsEntry

Returns:

a new entry.

Throws:

java.lang.ClassCastException - if the provided entry is not of type DFOEntry

getInstance

public IndexEntry getInstance(java.lang.Object name)

Gets a new instance of the implementing class.

Parameters:

name - The name to give the new instance.

getPostings

protected Postings getPostings()

Gets the appropriate postings type for the class. These postings should be useable for indexing.

Specified by:

getPostings in class SinglePostingsEntry

Returns:

Postings suitable for use when indexing.

getPostings

protected Postings getPostings(ReadableBuffer input)

Reads the postings for this class, returning a set of postings useful at query time.

Specified by:

getPostings in class SinglePostingsEntry

Parameters:

input - The buffer containing the postings read from the postings file.

Returns:

The postings for this entry.

writePostings

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

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

Specified by:

writePostings in interface IndexEntry

Overrides:

writePostings in class SinglePostingsEntry

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.

encodePostingsInfo

public void encodePostingsInfo(WriteableBuffer b)

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

Specified by:

encodePostingsInfo in interface IndexEntry

Overrides:

encodePostingsInfo in class SinglePostingsEntry

Parameters:

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

decodePostingsInfo

public void decodePostingsInfo(ReadableBuffer b,
                               int pos)

Decodes the postings information associated with this entry.

Specified by:

decodePostingsInfo in interface QueryEntry

Overrides:

decodePostingsInfo in class SinglePostingsEntry

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

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.

Specified by:

readPostings in interface QueryEntry

Overrides:

readPostings in class SinglePostingsEntry

Throws:

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

getTotalOccurrences

public long getTotalOccurrences()

Gets the total number of occurrences associated with this entry. For this base class, this is the same as n.

Specified by:

getTotalOccurrences in interface Entry

Overrides:

getTotalOccurrences in class SinglePostingsEntry

Returns:

The total number of occurrences associated with this entry.

getMaxFDT

public int getMaxFDT()

Gets the maximum frequency in the postings associated with this entry. For this base class, this is always 1.

Specified by:

getMaxFDT in interface Entry

Overrides:

getMaxFDT in class SinglePostingsEntry

hasPositionInformation

public boolean hasPositionInformation()

Description copied from interface: QueryEntry

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

Specified by:

hasPositionInformation in interface QueryEntry

Overrides:

hasPositionInformation in class SinglePostingsEntry

hasFieldInformation

public boolean hasFieldInformation()

Description copied from interface: QueryEntry

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

Specified by:

hasFieldInformation in interface QueryEntry

Overrides:

hasFieldInformation in class SinglePostingsEntry

iterator

public PostingsIterator iterator(PostingsIteratorFeatures features)

Gets an iterator that will iterate through a set of postings associated with this entry.

Specified by:

iterator in interface QueryEntry

Overrides:

iterator in class SinglePostingsEntry

Parameters:

features - The features that the iterator must support

Returns:

An iterator for the postings.