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Diffstat (limited to '3rdparty/clucene/src/CLucene/search/Sort.h')
| -rw-r--r-- | 3rdparty/clucene/src/CLucene/search/Sort.h | 356 |
1 files changed, 356 insertions, 0 deletions
diff --git a/3rdparty/clucene/src/CLucene/search/Sort.h b/3rdparty/clucene/src/CLucene/search/Sort.h new file mode 100644 index 000000000..cfe96d56c --- /dev/null +++ b/3rdparty/clucene/src/CLucene/search/Sort.h @@ -0,0 +1,356 @@ +/*------------------------------------------------------------------------------ +* Copyright (C) 2003-2006 Ben van Klinken and the CLucene Team +* +* Distributable under the terms of either the Apache License (Version 2.0) or +* the GNU Lesser General Public License, as specified in the COPYING file. +------------------------------------------------------------------------------*/ +#ifndef _lucene_search_Sort_ +#define _lucene_search_Sort_ + +#if defined(_LUCENE_PRAGMA_ONCE) +# pragma once +#endif + +#include "CLucene/index/IndexReader.h" +#include "SearchHeader.h" + +CL_NS_DEF(search) + + class SortField; //predefine + class Sort; + +/** + * Expert: Compares two ScoreDoc objects for sorting. + * + */ + class ScoreDocComparator:LUCENE_BASE { + protected: + ScoreDocComparator(){} + public: + virtual ~ScoreDocComparator(); +// CL_NS(util)::Comparable** cachedValues; +// ScoreDocComparator(CL_NS(util)::Comparable** cachedValues); + + /** + * Compares two ScoreDoc objects and returns a result indicating their + * sort order. + * @param i First ScoreDoc + * @param j Second ScoreDoc + * @return <code>-1</code> if <code>i</code> should come before <code>j</code><br><code>1</code> if <code>i</code> should come after <code>j</code><br><code>0</code> if they are equal + * @see java.util.Comparator + */ + virtual int32_t compare (struct ScoreDoc* i, struct ScoreDoc* j) = 0; + + /** + * Returns the value used to sort the given document. The + * object returned must implement the java.io.Serializable + * interface. This is used by multisearchers to determine how to collate results from their searchers. + * @see FieldDoc + * @param i Document + * @return Serializable object + */ + virtual CL_NS(util)::Comparable* sortValue (struct ScoreDoc* i) = 0; + + + /** + * Returns the type of sort. Should return <code>SortField.SCORE</code>, <code>SortField.DOC</code>, <code>SortField.STRING</code>, <code>SortField.INTEGER</code>, + * <code>SortField::FLOAT</code> or <code>SortField.CUSTOM</code>. It is not valid to return <code>SortField.AUTO</code>. + * This is used by multisearchers to determine how to collate results from their searchers. + * @return One of the constants in SortField. + * @see SortField + */ + virtual int32_t sortType() = 0; + + /** Special comparator for sorting hits according to computed relevance (document score). */ + static ScoreDocComparator* RELEVANCE; + + /** Special comparator for sorting hits according to index order (document number). */ + static ScoreDocComparator* INDEXORDER; + }; + +/** + * Expert: returns a comparator for sorting ScoreDocs. + * + */ +class SortComparatorSource:LUCENE_BASE { +public: + virtual ~SortComparatorSource(){ + } + + /** + * return a reference to a string describing the name of the comparator + * this is used in the explanation + */ + virtual TCHAR* getName() = 0; + + virtual size_t hashCode() = 0; + + /** + * Creates a comparator for the field in the given index. + * @param reader Index to create comparator for. + * @param fieldname Field to create comparator for. + * @return Comparator of ScoreDoc objects. + * @throws IOException If an error occurs reading the index. + */ + virtual ScoreDocComparator* newComparator (CL_NS(index)::IndexReader* reader, const TCHAR* fieldname) = 0; +}; + + +/** + * Abstract base class for sorting hits returned by a Query. + * + * <p>This class should only be used if the other SortField + * types (SCORE, DOC, STRING, INT, FLOAT) do not provide an + * adequate sorting. It maintains an internal cache of values which + * could be quite large. The cache is an array of Comparable, + * one for each document in the index. There is a distinct + * Comparable for each unique term in the field - if + * some documents have the same term in the field, the cache + * array will have entries which reference the same Comparable. + * + */ +class SortComparator: public SortComparatorSource { +public: + virtual ScoreDocComparator* newComparator (CL_NS(index)::IndexReader* reader, const TCHAR* fieldname); + + SortComparator(); + virtual ~SortComparator(); + + /** + * Returns an object which, when sorted according to natural order, + * will order the Term values in the correct order. + * <p>For example, if the Terms contained integer values, this method + * would return <code>new Integer(termtext)</code>. Note that this + * might not always be the most efficient implementation - for this + * particular example, a better implementation might be to make a + * ScoreDocLookupComparator that uses an internal lookup table of int. + * @param termtext The textual value of the term. + * @return An object representing <code>termtext</code> that sorts + * according to the natural order of <code>termtext</code>. + * @see Comparable + * @see ScoreDocComparator + */ + virtual CL_NS(util)::Comparable* getComparable (const TCHAR* termtext) = 0; + +}; + + +/** + * Stores information about how to sort documents by terms in an individual + * field. Fields must be indexed in order to sort by them. + * + */ +class SortField:LUCENE_BASE { +private: + const TCHAR* field; + int32_t type; // defaults to determining type dynamically + //Locale* locale; // defaults to "natural order" (no Locale) + bool reverse; // defaults to natural order + SortComparatorSource* factory; + +protected: + SortField (const SortField& clone); +public: + virtual ~SortField(); + + /** Sort by document score (relevancy). Sort values are Float and higher + * values are at the front. + * PORTING: this is the same as SCORE in java, it had to be renamed because + * SCORE is a system macro on some platforms (AIX). + */ + LUCENE_STATIC_CONSTANT(int32_t, DOCSCORE=0); + + /** Sort by document number (index order). Sort values are Integer and lower + * values are at the front. */ + LUCENE_STATIC_CONSTANT(int32_t, DOC=1); + + /** Guess type of sort based on field contents. A regular expression is used + * to look at the first term indexed for the field and determine if it + * represents an integer number, a floating point number, or just arbitrary + * string characters. */ + LUCENE_STATIC_CONSTANT(int32_t, AUTO=2); + + /** Sort using term values as Strings. Sort values are String and lower + * values are at the front. */ + LUCENE_STATIC_CONSTANT(int32_t, STRING=3); + + /** Sort using term values as encoded Integers. Sort values are Integer and + * lower values are at the front. */ + LUCENE_STATIC_CONSTANT(int32_t, INT=4); + + /** Sort using term values as encoded Floats. Sort values are Float and + * lower values are at the front. */ + LUCENE_STATIC_CONSTANT(int32_t, FLOAT=5); + + /** Sort using a custom Comparator. Sort values are any Comparable and + * sorting is done according to natural order. */ + LUCENE_STATIC_CONSTANT(int32_t, CUSTOM=9); + + // IMPLEMENTATION NOTE: the FieldCache.STRING_INDEX is in the same "namespace" + // as the above static int values. Any new values must not have the same value + // as FieldCache.STRING_INDEX. + + /** Represents sorting by document score (relevancy). */ + static SortField* FIELD_SCORE; + + /** Represents sorting by document number (index order). */ + static SortField* FIELD_DOC; + + SortField (const TCHAR* field); + //SortField (const TCHAR* field, bool reverse); + //todo: we cannot make reverse use default field of =false. + //because bool and int are the same type in c, overloading is not possible + SortField (const TCHAR* field, int32_t type, bool reverse); + + /* + SortField (TCHAR* field, Locale* locale) { + SortField (TCHAR* field, Locale* locale, bool reverse);*/ + + SortField (const TCHAR* field, SortComparatorSource* comparator, bool reverse=false); + + /** Returns the name of the field. Could return <code>null</code> + * if the sort is by SCORE or DOC. + * @return Name of field, possibly <code>null</code>. + */ + const TCHAR* getField() const { return field; } + + SortField* clone() const; + + /** Returns the type of contents in the field. + * @return One of the constants SCORE, DOC, AUTO, STRING, INT or FLOAT. + */ + int32_t getType() const { return type; } + + /** Returns the Locale by which term values are interpreted. + * May return <code>null</code> if no Locale was specified. + * @return Locale, or <code>null</code>. + */ + /*Locale getLocale() { + return locale; + }*/ + + /** Returns whether the sort should be reversed. + * @return True if natural order should be reversed. + */ + bool getReverse() const { return reverse; } + + SortComparatorSource* getFactory() const { return factory; } + + TCHAR* toString() const; +}; + + + +/** + * Encapsulates sort criteria for returned hits. + * + * <p>The fields used to determine sort order must be carefully chosen. + * Documents must contain a single term in such a field, + * and the value of the term should indicate the document's relative position in + * a given sort order. The field must be indexed, but should not be tokenized, + * and does not need to be stored (unless you happen to want it back with the + * rest of your document data). In other words: + * + * <dl><dd><code>document.add (new Field ("byNumber", Integer.toString(x), false, true, false));</code> + * </dd></dl> + * + * <p><h3>Valid Types of Values</h3> + * + * <p>There are three possible kinds of term values which may be put into + * sorting fields: Integers, Floats, or Strings. Unless + * {@link SortField SortField} objects are specified, the type of value + * in the field is determined by parsing the first term in the field. + * + * <p>Integer term values should contain only digits and an optional + * preceeding negative sign. Values must be base 10 and in the range + * <code>Integer.MIN_VALUE</code> and <code>Integer.MAX_VALUE</code> inclusive. + * Documents which should appear first in the sort + * should have low value integers, later documents high values + * (i.e. the documents should be numbered <code>1..n</code> where + * <code>1</code> is the first and <code>n</code> the last). + * + * <p>Float term values should conform to values accepted by + * {@link Float Float.valueOf(String)} (except that <code>NaN</code> + * and <code>Infinity</code> are not supported). + * Documents which should appear first in the sort + * should have low values, later documents high values. + * + * <p>String term values can contain any valid String, but should + * not be tokenized. The values are sorted according to their + * {@link Comparable natural order}. Note that using this type + * of term value has higher memory requirements than the other + * two types. + * + * <p><h3>Object Reuse</h3> + * + * <p>One of these objects can be + * used multiple times and the sort order changed between usages. + * + * <p>This class is thread safe. + * + * <p><h3>Memory Usage</h3> + * + * <p>Sorting uses of caches of term values maintained by the + * internal HitQueue(s). The cache is static and contains an integer + * or float array of length <code>IndexReader.maxDoc()</code> for each field + * name for which a sort is performed. In other words, the size of the + * cache in bytes is: + * + * <p><code>4 * IndexReader.maxDoc() * (# of different fields actually used to sort)</code> + * + * <p>For String fields, the cache is larger: in addition to the + * above array, the value of every term in the field is kept in memory. + * If there are many unique terms in the field, this could + * be quite large. + * + * <p>Note that the size of the cache is not affected by how many + * fields are in the index and <i>might</i> be used to sort - only by + * the ones actually used to sort a result set. + * + * <p>The cache is cleared each time a new <code>IndexReader</code> is + * passed in, or if the value returned by <code>maxDoc()</code> + * changes for the current IndexReader. This class is not set up to + * be able to efficiently sort hits from more than one index + * simultaneously. + * + */ +class Sort:LUCENE_BASE { + // internal representation of the sort criteria + SortField** fields; + void clear(); +public: + ~Sort(); + + /** Represents sorting by computed relevance. Using this sort criteria + * returns the same results as calling {@link Searcher#search(Query) Searcher#search()} + * without a sort criteria, only with slightly more overhead. */ + static Sort* RELEVANCE; + + /** Represents sorting by index order. */ + static Sort* INDEXORDER; + + Sort(); + Sort (const TCHAR* field, bool reverse=false); + Sort (const TCHAR** fields); + Sort (SortField* field); + Sort (SortField** fields); + void setSort (const TCHAR* field, bool reverse=false); + void setSort (const TCHAR** fieldnames); + void setSort (SortField* field); + void setSort (SortField** fields); + + TCHAR* toString() const; + + /** + * Representation of the sort criteria. + * @return a pointer to the of SortField array used in this sort criteria + */ + SortField** getSort() const{ return fields; } +}; + + + + + +CL_NS_END +#endif |