ANDQueryOp (Terrier Information Retrieval Platform 5.7 API)

java.lang.Object

org.terrier.matching.matchops.Operator

org.terrier.matching.matchops.MultiTermOp

org.terrier.matching.matchops.ANDQueryOp

All Implemented Interfaces:: java.io.Serializable, java.lang.Cloneable

Direct Known Subclasses:: PhraseOp, UnorderedWindowOp

public class ANDQueryOp
extends MultiTermOp

This combines multiple operators into a single op, where must all occur in a document. It is logically equivalent to Indri's #band() operator.

Since:: 5.0
See Also:: Serialized Form

Field Summary

Fields

Modifier and Type Field Description

static java.lang.String STRING_PREFIX

Fields inherited from class org.terrier.matching.matchops.MultiTermOp
logger

Fields inherited from class org.terrier.matching.matchops.Operator
IGNORE_LOW_IDF_TERMS
Constructor Summary

Constructors

Constructor Description

ANDQueryOp(java.lang.String[] ts)

ANDQueryOp(Operator[] ts)

Method Summary

Modifier and Type	Method	Description
`protected IterablePosting`	`createFinalPostingIterator(java.util.List<IterablePosting> postings, java.util.List<EntryStatistics> pointers)`
`protected EntryStatistics`	`mergeStatistics(EntryStatistics[] entryStats, CollectionStatistics collStats)`	Adjust the statistics for this operator: 1.
`java.lang.String`	`toString()`

Methods inherited from class org.terrier.matching.matchops.MultiTermOp

addStatistics, clone, getConstituents, getMatcher, getPostingIterator

Methods inherited from class org.terrier.matching.matchops.Operator

equals, hashCode, parse

Methods inherited from class java.lang.Object

finalize, getClass, notify, notifyAll, wait, wait, wait

Field Details
- STRING_PREFIX
  
  public static final java.lang.String STRING_PREFIX
  
  See Also:
  
  Constant Field Values
Constructor Details
- ANDQueryOp
  
  public ANDQueryOp(java.lang.String[] ts)
- ANDQueryOp
  
  public ANDQueryOp(Operator[] ts)
Method Details
- createFinalPostingIterator
  
  protected IterablePosting createFinalPostingIterator(java.util.List<IterablePosting> postings, java.util.List<EntryStatistics> pointers) throws java.io.IOException
  
  Specified by:
  
  createFinalPostingIterator in class MultiTermOp
  
  Throws:
  
  java.io.IOException
- mergeStatistics
  
  protected EntryStatistics mergeStatistics(EntryStatistics[] entryStats, CollectionStatistics collStats)
  
  Adjust the statistics for this operator: 1. The number of occurrences is the minimum of the constituent frequencies (handled by super). 2. The in-document maxTF is the minimum of the constituent maxTFs
  
  Overrides:
  
  mergeStatistics in class MultiTermOp
- toString
  
  public java.lang.String toString()
  
  Specified by:
  
  toString in class Operator