xapian-core
1.4.27
|
Public Member Functions | |
MyOddWeightingPostingSource (const Xapian::Database &db) | |
PostingSource * | clone () const override |
Clone the posting source. More... | |
void | init (const Xapian::Database &) override |
Set this PostingSource to the start of the list of postings. More... | |
double | get_weight () const override |
Return the weight contribution for the current document. More... | |
Xapian::doccount | get_termfreq_min () const override |
A lower bound on the number of documents this object can return. More... | |
Xapian::doccount | get_termfreq_est () const override |
An estimate of the number of documents this object can return. More... | |
Xapian::doccount | get_termfreq_max () const override |
An upper bound on the number of documents this object can return. More... | |
void | next (double wt) override |
Advance the current position to the next matching document. More... | |
void | skip_to (Xapian::docid to_did, double wt) override |
Advance to the specified docid. More... | |
bool | at_end () const override |
Return true if the current position is past the last entry in this list. More... | |
Xapian::docid | get_docid () const override |
Return the current docid. More... | |
string | get_description () const override |
Return a string describing this object. More... | |
Public Member Functions inherited from Xapian::PostingSource | |
PostingSource () | |
Allow subclasses to be instantiated. More... | |
virtual | ~PostingSource () |
void | set_maxweight (double max_weight) |
Specify an upper bound on what get_weight() will return from now on. More... | |
double | get_maxweight () const |
Return the currently set upper bound on what get_weight() can return. More... | |
virtual bool | check (Xapian::docid did, double min_wt) |
Check if the specified docid occurs. More... | |
virtual std::string | name () const |
Name of the posting source class. More... | |
virtual std::string | serialise () const |
Serialise object parameters into a string. More... | |
virtual PostingSource * | unserialise (const std::string &serialised) const |
Create object given string serialisation returned by serialise(). More... | |
virtual PostingSource * | unserialise_with_registry (const std::string &serialised, const Registry ®istry) const |
Create object given string serialisation returned by serialise(). More... | |
PostingSource * | release () |
Start reference counting this object. More... | |
const PostingSource * | release () const |
Start reference counting this object. More... | |
Public Member Functions inherited from Xapian::Internal::opt_intrusive_base | |
opt_intrusive_base (const opt_intrusive_base &) | |
opt_intrusive_base & | operator= (const opt_intrusive_base &) |
opt_intrusive_base () | |
Construct object which is initially not reference counted. More... | |
virtual | ~opt_intrusive_base () |
void | ref () const |
void | unref () const |
Private Member Functions | |
MyOddWeightingPostingSource (Xapian::doccount num_docs_, Xapian::doccount last_docid_) | |
Private Attributes | |
Xapian::doccount | num_docs |
Xapian::doccount | last_docid |
Xapian::docid | did |
Additional Inherited Members | |
Public Attributes inherited from Xapian::Internal::opt_intrusive_base | |
unsigned | _refs |
Reference count. More... | |
Protected Member Functions inherited from Xapian::Internal::opt_intrusive_base | |
void | release () const |
Start reference counting. More... | |
Definition at line 139 of file api_postingsource.cc.
|
inlineprivate |
Definition at line 146 of file api_postingsource.cc.
|
inline |
Definition at line 154 of file api_postingsource.cc.
|
inlineoverridevirtual |
Return true if the current position is past the last entry in this list.
At least one of next(), skip_to() or check() will be called before this method is first called.
Implements Xapian::PostingSource.
Definition at line 185 of file api_postingsource.cc.
|
inlineoverridevirtual |
Clone the posting source.
The clone should inherit the configuration of the parent, but need not inherit the state. ie, the clone does not need to be in the same iteration position as the original: the matcher will always call init() on the clone before attempting to move the iterator, or read the information about the current position of the iterator.
This may return NULL to indicate that cloning is not supported. In this case, the PostingSource may only be used with a single-database search.
The default implementation returns NULL.
Note that the returned object will be deallocated by Xapian after use with "delete". If you want to handle the deletion in a special way (for example when wrapping the Xapian API for use from another language) then you can define a static operator delete
method in your subclass as shown here: https://trac.xapian.org/ticket/554#comment:1
Reimplemented from Xapian::PostingSource.
Definition at line 158 of file api_postingsource.cc.
|
inlineoverridevirtual |
Return a string describing this object.
This default implementation returns a generic answer. This default it provided to avoid forcing those deriving their own PostingSource subclass from having to implement this (they may not care what get_description() gives for their subclass).
Reimplemented from Xapian::PostingSource.
Definition at line 192 of file api_postingsource.cc.
|
inlineoverridevirtual |
Return the current docid.
This method may assume that it will only be called when there is a "current document". See get_weight() for details.
Note: in the case of a multi-database search, the returned docid should be in the single subdatabase relevant to this posting source. See the init() method for details.
Implements Xapian::PostingSource.
Definition at line 190 of file api_postingsource.cc.
|
inlineoverridevirtual |
An estimate of the number of documents this object can return.
It must always be true that:
get_termfreq_min() <= get_termfreq_est() <= get_termfreq_max()
Xapian will always call init() on a PostingSource before calling this for the first time.
Implements Xapian::PostingSource.
Definition at line 171 of file api_postingsource.cc.
|
inlineoverridevirtual |
An upper bound on the number of documents this object can return.
Xapian will always call init() on a PostingSource before calling this for the first time.
Implements Xapian::PostingSource.
Definition at line 173 of file api_postingsource.cc.
|
inlineoverridevirtual |
A lower bound on the number of documents this object can return.
Xapian will always call init() on a PostingSource before calling this for the first time.
Implements Xapian::PostingSource.
Definition at line 169 of file api_postingsource.cc.
|
inlineoverridevirtual |
Return the weight contribution for the current document.
This default implementation always returns 0, for convenience when implementing "weight-less" PostingSource subclasses.
This method may assume that it will only be called when there is a "current document". In detail: Xapian will always call init() on a PostingSource before calling this for the first time. It will also only call this if the PostingSource reports that it is pointing to a valid document (ie, it will not call it before calling at least one of next(), skip_to() or check(), and will ensure that the PostingSource is not at the end by calling at_end()).
Reimplemented from Xapian::PostingSource.
Definition at line 164 of file api_postingsource.cc.
|
inlineoverridevirtual |
Set this PostingSource to the start of the list of postings.
This is called automatically by the matcher prior to each query being processed.
If a PostingSource is used for multiple searches, init() will therefore be called multiple times, and must handle this by using the database passed in the most recent call.
db | The database which the PostingSource should iterate through. |
Note: in the case of a multi-database search, a separate PostingSource will be used for each database (the separate PostingSources will be obtained using clone()), and each PostingSource will be passed one of the sub-databases as the db parameter here. The db parameter will therefore always refer to a single database. All docids passed to, or returned from, the PostingSource refer to docids in that single database, rather than in the multi-database.
Implements Xapian::PostingSource.
Definition at line 162 of file api_postingsource.cc.
|
inlineoverridevirtual |
Advance the current position to the next matching document.
The PostingSource starts before the first entry in the list, so next(), skip_to() or check() must be called before any methods which need the context of the current position.
Xapian will always call init() on a PostingSource before calling this for the first time.
min_wt | The minimum weight contribution that is needed (this is just a hint which subclasses may ignore). |
Implements Xapian::PostingSource.
Definition at line 175 of file api_postingsource.cc.
|
inlineoverridevirtual |
Advance to the specified docid.
If the specified docid isn't in the list, position ourselves on the first document after it (or at_end() if no greater docids are present).
If the current position is already the specified docid, this method will leave the position unmodified.
If the specified docid is earlier than the current position, the behaviour is unspecified. A sensible behaviour would be to leave the current position unmodified, but it is also reasonable to move to the specified docid.
The default implementation calls next() repeatedly, which works but skip_to() can often be implemented much more efficiently.
Xapian will always call init() on a PostingSource before calling this for the first time.
Note: in the case of a multi-database search, the docid specified is the docid in the single subdatabase relevant to this posting source. See the init() method for details.
did | The document id to advance to. |
min_wt | The minimum weight contribution that is needed (this is just a hint which subclasses may ignore). |
Reimplemented from Xapian::PostingSource.
Definition at line 180 of file api_postingsource.cc.
|
private |
Definition at line 144 of file api_postingsource.cc.
|
private |
Definition at line 142 of file api_postingsource.cc.
|
private |
Definition at line 140 of file api_postingsource.cc.