org.apache.lucene.store.instantiated
Class InstantiatedIndexReader

java.lang.Object
  extended by org.apache.lucene.index.IndexReader
      extended by org.apache.lucene.store.instantiated.InstantiatedIndexReader
All Implemented Interfaces:
Closeable, Cloneable

public class InstantiatedIndexReader
extends IndexReader

An InstantiatedIndexReader is not a snapshot in time, it is completely in sync with the latest commit to the store!

Consider using InstantiatedIndex as if it was immutable.


Nested Class Summary
 
Nested classes/interfaces inherited from class org.apache.lucene.index.IndexReader
IndexReader.FieldOption
 
Field Summary
 
Fields inherited from class org.apache.lucene.index.IndexReader
hasChanges
 
Constructor Summary
InstantiatedIndexReader(InstantiatedIndex index)
           
 
Method Summary
 Directory directory()
          Returns the directory associated with this index.
 int docFreq(Term t)
          Returns the number of documents containing the term t.
protected  void doClose()
          Implements close.
protected  void doCommit(Map commitUserData)
          Implements commit.
 Document document(int n)
          Returns the stored fields of the nth Document in this index.
 Document document(int n, FieldSelector fieldSelector)
          Return the Document at the nth position.
protected  void doDelete(int docNum)
          Implements deletion of the document numbered docNum.
protected  void doSetNorm(int doc, String field, byte value)
          Implements setNorm in subclass.
protected  void doUndeleteAll()
          Implements actual undeleteAll() in subclass.
 Collection getFieldNames(IndexReader.FieldOption fieldOption)
          Get a list of unique field names that exist in this index and have the specified field option information.
 InstantiatedIndex getIndex()
           
 TermFreqVector getTermFreqVector(int docNumber, String field)
          Return a term frequency vector for the specified document and field.
 void getTermFreqVector(int docNumber, String field, TermVectorMapper mapper)
          Load the Term Vector into a user-defined data structure instead of relying on the parallel arrays of the TermFreqVector.
 void getTermFreqVector(int docNumber, TermVectorMapper mapper)
          Map all the term vectors for all fields in a Document
 TermFreqVector[] getTermFreqVectors(int docNumber)
          Return an array of term frequency vectors for the specified document.
 long getVersion()
          An InstantiatedIndexReader is not a snapshot in time, it is completely in sync with the latest commit to the store!
 boolean hasDeletions()
          Returns true if any documents have been deleted
 boolean isCurrent()
          An InstantiatedIndexReader is always current! Check whether this IndexReader is still using the current (i.e., most recently committed) version of the index.
 boolean isDeleted(int n)
          Returns true if document n has been deleted
 boolean isOptimized()
          Checks is the index is optimized (if it has a single segment and no deletions).
 int maxDoc()
          Returns one greater than the largest possible document number.
 byte[] norms(String field)
          never ever touch these values.
 void norms(String field, byte[] bytes, int offset)
          Reads the byte-encoded normalization factor for the named field of every document.
 int numDocs()
          Returns the number of documents in this index.
 TermDocs termDocs()
          Returns an unpositioned TermDocs enumerator.
 TermDocs termDocs(Term term)
          Returns an enumeration of all the documents which contain term.
 TermPositions termPositions()
          Returns an unpositioned TermPositions enumerator.
 TermEnum terms()
          Returns an enumeration of all the terms in the index.
 TermEnum terms(Term t)
          Returns an enumeration of all terms starting at a given term.
 
Methods inherited from class org.apache.lucene.index.IndexReader
acquireWriteLock, clone, clone, close, commit, commit, decRef, deleteDocument, deleteDocuments, ensureOpen, flush, flush, getCommitUserData, getCommitUserData, getCurrentVersion, getDeletesCacheKey, getFieldCacheKey, getIndexCommit, getRefCount, getSequentialSubReaders, getTermInfosIndexDivisor, getUniqueTermCount, hasNorms, incRef, indexExists, lastModified, listCommits, main, numDeletedDocs, open, open, open, open, open, open, open, reopen, reopen, reopen, setNorm, setNorm, termPositions, undeleteAll
 
Methods inherited from class java.lang.Object
equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Constructor Detail

InstantiatedIndexReader

public InstantiatedIndexReader(InstantiatedIndex index)
Method Detail

isOptimized

public boolean isOptimized()
Description copied from class: IndexReader
Checks is the index is optimized (if it has a single segment and no deletions). Not implemented in the IndexReader base class.

Overrides:
isOptimized in class IndexReader
Returns:
always true.

getVersion

public long getVersion()
An InstantiatedIndexReader is not a snapshot in time, it is completely in sync with the latest commit to the store!

Overrides:
getVersion in class IndexReader
Returns:
output from InstantiatedIndex.getVersion() in associated instantiated index.

directory

public Directory directory()
Description copied from class: IndexReader
Returns the directory associated with this index. The Default implementation returns the directory specified by subclasses when delegating to the IndexReader(Directory) constructor, or throws an UnsupportedOperationException if one was not specified.

Overrides:
directory in class IndexReader

isCurrent

public boolean isCurrent()
                  throws IOException
An InstantiatedIndexReader is always current! Check whether this IndexReader is still using the current (i.e., most recently committed) version of the index. If a writer has committed any changes to the index since this reader was opened, this will return false, in which case you must open a new IndexReader in order to see the changes. See the description of the autoCommit flag which controls when the IndexWriter actually commits changes to the index.

Overrides:
isCurrent in class IndexReader
Returns:
always true
Throws:
CorruptIndexException - if the index is corrupt
IOException - if there is a low-level IO error
UnsupportedOperationException - unless overridden in subclass

getIndex

public InstantiatedIndex getIndex()

numDocs

public int numDocs()
Description copied from class: IndexReader
Returns the number of documents in this index.

Specified by:
numDocs in class IndexReader

maxDoc

public int maxDoc()
Description copied from class: IndexReader
Returns one greater than the largest possible document number. This may be used to, e.g., determine how big to allocate an array which will have an element for every document number in an index.

Specified by:
maxDoc in class IndexReader

hasDeletions

public boolean hasDeletions()
Description copied from class: IndexReader
Returns true if any documents have been deleted

Specified by:
hasDeletions in class IndexReader

isDeleted

public boolean isDeleted(int n)
Description copied from class: IndexReader
Returns true if document n has been deleted

Specified by:
isDeleted in class IndexReader

doDelete

protected void doDelete(int docNum)
                 throws IOException
Description copied from class: IndexReader
Implements deletion of the document numbered docNum. Applications should call IndexReader.deleteDocument(int) or IndexReader.deleteDocuments(Term).

Specified by:
doDelete in class IndexReader
Throws:
IOException

doUndeleteAll

protected void doUndeleteAll()
                      throws IOException
Description copied from class: IndexReader
Implements actual undeleteAll() in subclass.

Specified by:
doUndeleteAll in class IndexReader
Throws:
IOException

doCommit

protected void doCommit(Map commitUserData)
                 throws IOException
Description copied from class: IndexReader
Implements commit.

Specified by:
doCommit in class IndexReader
Throws:
IOException

doClose

protected void doClose()
                throws IOException
Description copied from class: IndexReader
Implements close.

Specified by:
doClose in class IndexReader
Throws:
IOException

getFieldNames

public Collection getFieldNames(IndexReader.FieldOption fieldOption)
Description copied from class: IndexReader
Get a list of unique field names that exist in this index and have the specified field option information.

Specified by:
getFieldNames in class IndexReader
Parameters:
fieldOption - specifies which field option should be available for the returned fields
Returns:
Collection of Strings indicating the names of the fields.
See Also:
IndexReader.FieldOption

document

public Document document(int n,
                         FieldSelector fieldSelector)
                  throws CorruptIndexException,
                         IOException
Return the Document at the nth position.

Warning! The resulting document is the actual stored document instance and not a deserialized clone as retuned by an IndexReader over a Directory. I.e., if you need to touch the document, clone it first!

This can also be seen as a feature for live changes of stored values, but be careful! Adding a field with an name unknown to the index or to a field with previously no stored values will make getFieldNames(org.apache.lucene.index.IndexReader.FieldOption) out of sync, causing problems for instance when merging the instantiated index to another index.

This implementation ignores the field selector! All stored fields are always returned!

Specified by:
document in class IndexReader
Parameters:
n - document number
fieldSelector - ignored
Returns:
The stored fields of the Document at the nth position
Throws:
CorruptIndexException - if the index is corrupt
IOException - if there is a low-level IO error
See Also:
Fieldable, FieldSelector, SetBasedFieldSelector, LoadFirstFieldSelector

document

public Document document(int n)
                  throws IOException
Returns the stored fields of the nth Document in this index.

Warning! The resulting document is the actual stored document instance and not a deserialized clone as retuned by an IndexReader over a Directory. I.e., if you need to touch the document, clone it first!

This can also be seen as a feature for live changes of stored values, but be careful! Adding a field with an name unknown to the index or to a field with previously no stored values will make getFieldNames(org.apache.lucene.index.IndexReader.FieldOption) out of sync, causing problems for instance when merging the instantiated index to another index.

Overrides:
document in class IndexReader
Throws:
CorruptIndexException - if the index is corrupt
IOException - if there is a low-level IO error

norms

public byte[] norms(String field)
             throws IOException
never ever touch these values. it is the true values, unless norms have been touched.

Specified by:
norms in class IndexReader
Throws:
IOException
See Also:
AbstractField.setBoost(float)

norms

public void norms(String field,
                  byte[] bytes,
                  int offset)
           throws IOException
Description copied from class: IndexReader
Reads the byte-encoded normalization factor for the named field of every document. This is used by the search code to score documents.

Specified by:
norms in class IndexReader
Throws:
IOException
See Also:
AbstractField.setBoost(float)

doSetNorm

protected void doSetNorm(int doc,
                         String field,
                         byte value)
                  throws IOException
Description copied from class: IndexReader
Implements setNorm in subclass.

Specified by:
doSetNorm in class IndexReader
Throws:
IOException

docFreq

public int docFreq(Term t)
            throws IOException
Description copied from class: IndexReader
Returns the number of documents containing the term t.

Specified by:
docFreq in class IndexReader
Throws:
IOException - if there is a low-level IO error

terms

public TermEnum terms()
               throws IOException
Description copied from class: IndexReader
Returns an enumeration of all the terms in the index. The enumeration is ordered by Term.compareTo(). Each term is greater than all that precede it in the enumeration. Note that after calling terms(), TermEnum.next() must be called on the resulting enumeration before calling other methods such as TermEnum.term().

Specified by:
terms in class IndexReader
Throws:
IOException - if there is a low-level IO error

terms

public TermEnum terms(Term t)
               throws IOException
Description copied from class: IndexReader
Returns an enumeration of all terms starting at a given term. If the given term does not exist, the enumeration is positioned at the first term greater than the supplied term. The enumeration is ordered by Term.compareTo(). Each term is greater than all that precede it in the enumeration.

Specified by:
terms in class IndexReader
Throws:
IOException - if there is a low-level IO error

termDocs

public TermDocs termDocs()
                  throws IOException
Description copied from class: IndexReader
Returns an unpositioned TermDocs enumerator.

Specified by:
termDocs in class IndexReader
Throws:
IOException - if there is a low-level IO error

termDocs

public TermDocs termDocs(Term term)
                  throws IOException
Description copied from class: IndexReader
Returns an enumeration of all the documents which contain term. For each document, the document number, the frequency of the term in that document is also provided, for use in search scoring. If term is null, then all non-deleted docs are returned with freq=1. Thus, this method implements the mapping:

The enumeration is ordered by document number. Each document number is greater than all that precede it in the enumeration.

Overrides:
termDocs in class IndexReader
Throws:
IOException - if there is a low-level IO error

termPositions

public TermPositions termPositions()
                            throws IOException
Description copied from class: IndexReader
Returns an unpositioned TermPositions enumerator.

Specified by:
termPositions in class IndexReader
Throws:
IOException - if there is a low-level IO error

getTermFreqVectors

public TermFreqVector[] getTermFreqVectors(int docNumber)
                                    throws IOException
Description copied from class: IndexReader
Return an array of term frequency vectors for the specified document. The array contains a vector for each vectorized field in the document. Each vector contains terms and frequencies for all terms in a given vectorized field. If no such fields existed, the method returns null. The term vectors that are returned may either be of type TermFreqVector or of type TermPositionVector if positions or offsets have been stored.

Specified by:
getTermFreqVectors in class IndexReader
Parameters:
docNumber - document for which term frequency vectors are returned
Returns:
array of term frequency vectors. May be null if no term vectors have been stored for the specified document.
Throws:
IOException - if index cannot be accessed
See Also:
Field.TermVector

getTermFreqVector

public TermFreqVector getTermFreqVector(int docNumber,
                                        String field)
                                 throws IOException
Description copied from class: IndexReader
Return a term frequency vector for the specified document and field. The returned vector contains terms and frequencies for the terms in the specified field of this document, if the field had the storeTermVector flag set. If termvectors had been stored with positions or offsets, a TermPositionVector is returned.

Specified by:
getTermFreqVector in class IndexReader
Parameters:
docNumber - document for which the term frequency vector is returned
field - field for which the term frequency vector is returned.
Returns:
term frequency vector May be null if field does not exist in the specified document or term vector was not stored.
Throws:
IOException - if index cannot be accessed
See Also:
Field.TermVector

getTermFreqVector

public void getTermFreqVector(int docNumber,
                              String field,
                              TermVectorMapper mapper)
                       throws IOException
Description copied from class: IndexReader
Load the Term Vector into a user-defined data structure instead of relying on the parallel arrays of the TermFreqVector.

Specified by:
getTermFreqVector in class IndexReader
Parameters:
docNumber - The number of the document to load the vector for
field - The name of the field to load
mapper - The TermVectorMapper to process the vector. Must not be null
Throws:
IOException - if term vectors cannot be accessed or if they do not exist on the field and doc. specified.

getTermFreqVector

public void getTermFreqVector(int docNumber,
                              TermVectorMapper mapper)
                       throws IOException
Description copied from class: IndexReader
Map all the term vectors for all fields in a Document

Specified by:
getTermFreqVector in class IndexReader
Parameters:
docNumber - The number of the document to load the vector for
mapper - The TermVectorMapper to process the vector. Must not be null
Throws:
IOException - if term vectors cannot be accessed or if they do not exist on the field and doc. specified.


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