java.lang.Object | ||
↳ | org.apache.lucene.index.IndexReader | |
↳ | org.apache.lucene.index.FilterIndexReader |
A FilterIndexReader
contains another IndexReader, which it
uses as its basic source of data, possibly transforming the data along the
way or providing additional functionality. The class
FilterIndexReader
itself simply implements all abstract methods
of IndexReader
with versions that pass all requests to the
contained index reader. Subclasses of FilterIndexReader
may
further override some of these methods and may also provide additional
methods and fields.
Nested Classes | |||||||||||
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FilterIndexReader.FilterTermDocs | Base class for filtering TermDocs implementations. |
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FilterIndexReader.FilterTermEnum | Base class for filtering TermEnum implementations. |
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FilterIndexReader.FilterTermPositions | Base class for filtering TermPositions implementations. |
Fields | |||||||||||
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in |
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Inherited Fields | |||||||||||
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From class
org.apache.lucene.index.IndexReader
|
Public Constructors | |||||||||||
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Construct a FilterIndexReader based on the specified base reader. |
Public Methods | |||||||||||
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Returns the directory associated with this index.
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Returns the number of documents containing the term
t . | |||||||||||
Get the
Document at the n
th position. | |||||||||||
If the subclass of FilteredIndexReader modifies the
deleted docs, you must override this method to provide
a different key
| |||||||||||
If the subclass of FilteredIndexReader modifies the
contents of the FieldCache, you must override this
method to provide a different key
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Get a list of unique field names that exist in this index and have the specified
field option information.
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Expert: returns the sequential sub readers that this
reader is logically composed of.
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Load the Term Vector into a user-defined data structure instead of relying on the parallel arrays of
the
TermFreqVector . | |||||||||||
Map all the term vectors for all fields in a Document
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Return a term frequency vector for the specified document and field.
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Return an array of term frequency vectors for the specified document.
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Version number when this IndexReader was opened.
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Returns true if any documents have been deleted
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Returns true if there are norms stored for this field.
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Check whether any new changes have occurred to the
index since this reader was opened.
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Returns true if document n has been deleted
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Checks is the index is optimized (if it has a single segment and
no deletions).
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Returns one greater than the largest possible document number.
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Returns the byte-encoded normalization factor for the named field of
every document.
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Reads the byte-encoded normalization factor for the named field of every
document.
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Returns the number of documents in this index.
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Returns an unpositioned
TermDocs enumerator. | |||||||||||
Returns an enumeration of all the documents which contain
term . | |||||||||||
Returns an unpositioned
TermPositions enumerator. | |||||||||||
Returns an enumeration of all terms starting at a given term.
| |||||||||||
Returns an enumeration of all the terms in the index.
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Protected Methods | |||||||||||
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Implements close.
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Implements commit.
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Implements deletion of the document numbered
docNum . | |||||||||||
Implements setNorm in subclass.
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Implements actual undeleteAll() in subclass.
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Inherited Methods | |||||||||||
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From class
org.apache.lucene.index.IndexReader
| |||||||||||
From class
java.lang.Object
| |||||||||||
From interface
java.io.Closeable
|
Construct a FilterIndexReader based on the specified base reader. Directory locking for delete, undeleteAll, and setNorm operations is left to the base reader.
Note that base reader is closed if this FilterIndexReader is closed.
in | specified base reader. |
---|
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.
Returns the number of documents containing the term t
.
IOException |
---|
Get the Document
at the n
th position. The FieldSelector
may be used to determine
what Field
s to load and how they should
be loaded. NOTE: If this Reader (more specifically, the underlying
FieldsReader
) is closed before the lazy
Field
is loaded an exception may be
thrown. If you want the value of a lazy
Field
to be available after closing you
must explicitly load it or fetch the Document again with a new loader.
NOTE: for performance reasons, this method does not check if the
requested document is deleted, and therefore asking for a deleted document
may yield unspecified results. Usually this is not required, however you
can call isDeleted(int)
with the requested document ID to verify
the document is not deleted.
n | Get the document at the n th position |
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fieldSelector | The FieldSelector to use to determine what
Fields should be loaded on the Document. May be null, in which case
all Fields will be loaded. |
Document
at the nth positionCorruptIndexException | |
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IOException |
If the subclass of FilteredIndexReader modifies the deleted docs, you must override this method to provide a different key
If the subclass of FilteredIndexReader modifies the contents of the FieldCache, you must override this method to provide a different key
Get a list of unique field names that exist in this index and have the specified field option information.
fieldNames | specifies which field option should be available for the returned fields |
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Expert: returns the sequential sub readers that this reader is logically composed of. For example, IndexSearcher uses this API to drive searching by one sub reader at a time. If this reader is not composed of sequential child readers, it should return null. If this method returns an empty array, that means this reader is a null reader (for example a MultiReader that has no sub readers).
NOTE: You should not try using sub-readers returned by
this method to make any changes (setNorm, deleteDocument,
etc.). While this might succeed for one composite reader
(like MultiReader), it will most likely lead to index
corruption for other readers (like DirectoryReader obtained
through open(IndexCommit, boolean)
. Use the parent reader directly.
Load the Term Vector into a user-defined data structure instead of relying on the parallel arrays of
the TermFreqVector
.
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 |
IOException |
---|
Map all the term vectors for all fields in a Document
docNumber | The number of the document to load the vector for |
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mapper | The TermVectorMapper to process the vector. Must not be null |
IOException |
---|
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.
docNumber | document for which the term frequency vector is returned |
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field | field for which the term frequency vector is returned. |
IOException |
---|
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.
docNumber | document for which term frequency vectors are returned |
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IOException |
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Version number when this IndexReader was opened. Not implemented in the IndexReader base class.
If this reader is based on a Directory (ie, was
created by calling open(IndexCommit, boolean)
, or reopen()
on
a reader based on a Directory), then this method
returns the version recorded in the commit that the
reader opened. This version is advanced every time
commit()
is called.
If instead this reader is a near real-time reader
(ie, obtained by a call to getReader()
, or by calling reopen()
on a near real-time reader), then this method returns
the version of the last commit done by the writer.
Note that even as further changes are made with the
writer, the version will not changed until a commit is
completed. Thus, you should not rely on this method to
determine when a near real-time reader should be
opened. Use isCurrent()
instead.
Returns true if any documents have been deleted
Returns true if there are norms stored for this field.
IOException |
---|
Check whether any new changes have occurred to the index since this reader was opened.
If this reader is based on a Directory (ie, was
created by calling open(IndexCommit, boolean)
, or reopen()
on
a reader based on a Directory), then this method checks
if any further commits (see commit()
have occurred in that directory).
If instead this reader is a near real-time reader
(ie, obtained by a call to getReader()
, or by calling reopen()
on a near real-time reader), then this method checks if
either a new commmit has occurred, or any new
uncommitted changes have taken place via the writer.
Note that even if the writer has only performed
merging, this method will still return false.
In any event, if this returns false, you should call
reopen()
to get a new reader that sees the
changes.
CorruptIndexException | |
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IOException |
Returns true if document n has been deleted
Checks is the index is optimized (if it has a single segment and no deletions). Not implemented in the IndexReader base class.
true
if the index is optimized; false
otherwiseReturns 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.
Returns the byte-encoded normalization factor for the named field of every document. This is used by the search code to score documents.
IOException |
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Reads the byte-encoded normalization factor for the named field of every document. This is used by the search code to score documents.
IOException |
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Returns the number of documents in this index.
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.
IOException |
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Returns an unpositioned TermPositions
enumerator.
IOException |
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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.
IOException |
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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(), next()
must be called
on the resulting enumeration before calling other methods such as
term()
.
IOException |
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Implements deletion of the document numbered docNum
.
Applications should call deleteDocument(int)
or deleteDocuments(Term)
.
CorruptIndexException | |
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IOException |
Implements setNorm in subclass.
CorruptIndexException | |
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IOException |
Implements actual undeleteAll() in subclass.
CorruptIndexException | |
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IOException |