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diff --git a/intl/icu/source/i18n/unicode/alphaindex.h b/intl/icu/source/i18n/unicode/alphaindex.h new file mode 100644 index 0000000000..cbce212717 --- /dev/null +++ b/intl/icu/source/i18n/unicode/alphaindex.h @@ -0,0 +1,766 @@ +// © 2016 and later: Unicode, Inc. and others. +// License & terms of use: http://www.unicode.org/copyright.html +/* +******************************************************************************* +* +* Copyright (C) 2011-2014 International Business Machines +* Corporation and others. All Rights Reserved. +* +******************************************************************************* +*/ + +#ifndef INDEXCHARS_H +#define INDEXCHARS_H + +#include "unicode/utypes.h" + +#if U_SHOW_CPLUSPLUS_API + +#include "unicode/uobject.h" +#include "unicode/locid.h" +#include "unicode/unistr.h" + +#if !UCONFIG_NO_COLLATION + +/** + * \file + * \brief C++ API: Index Characters + */ + +U_CDECL_BEGIN + +/** + * Constants for Alphabetic Index Label Types. + * The form of these enum constants anticipates having a plain C API + * for Alphabetic Indexes that will also use them. + * @stable ICU 4.8 + */ +typedef enum UAlphabeticIndexLabelType { + /** + * Normal Label, typically the starting letter of the names + * in the bucket with this label. + * @stable ICU 4.8 + */ + U_ALPHAINDEX_NORMAL = 0, + + /** + * Underflow Label. The bucket with this label contains names + * in scripts that sort before any of the bucket labels in this index. + * @stable ICU 4.8 + */ + U_ALPHAINDEX_UNDERFLOW = 1, + + /** + * Inflow Label. The bucket with this label contains names + * in scripts that sort between two of the bucket labels in this index. + * Inflow labels are created when an index contains normal labels for + * multiple scripts, and skips other scripts that sort between some of the + * included scripts. + * @stable ICU 4.8 + */ + U_ALPHAINDEX_INFLOW = 2, + + /** + * Overflow Label. The bucket with this label contains names in scripts + * that sort after all of the bucket labels in this index. + * @stable ICU 4.8 + */ + U_ALPHAINDEX_OVERFLOW = 3 +} UAlphabeticIndexLabelType; + + +struct UHashtable; +U_CDECL_END + +U_NAMESPACE_BEGIN + +// Forward Declarations + +class BucketList; +class Collator; +class RuleBasedCollator; +class StringEnumeration; +class UnicodeSet; +class UVector; + +/** + * AlphabeticIndex supports the creation of a UI index appropriate for a given language. + * It can support either direct use, or use with a client that doesn't support localized collation. + * The following is an example of what an index might look like in a UI: + * + * <pre> + * <b>... A B C D E F G H I J K L M N O P Q R S T U V W X Y Z ...</b> + * + * <b>A</b> + * Addison + * Albertson + * Azensky + * <b>B</b> + * Baker + * ... + * </pre> + * + * The class can generate a list of labels for use as a UI "index", that is, a list of + * clickable characters (or character sequences) that allow the user to see a segment + * (bucket) of a larger "target" list. That is, each label corresponds to a bucket in + * the target list, where everything in the bucket is greater than or equal to the character + * (according to the locale's collation). Strings can be added to the index; + * they will be in sorted order in the right bucket. + * <p> + * The class also supports having buckets for strings before the first (underflow), + * after the last (overflow), and between scripts (inflow). For example, if the index + * is constructed with labels for Russian and English, Greek characters would fall + * into an inflow bucket between the other two scripts. + * <p> + * The AlphabeticIndex class is not intended for public subclassing. + * + * <p><em>Note:</em> If you expect to have a lot of ASCII or Latin characters + * as well as characters from the user's language, + * then it is a good idea to call addLabels(Locale::getEnglish(), status).</p> + * + * <h2>Direct Use</h2> + * <p>The following shows an example of building an index directly. + * The "show..." methods below are just to illustrate usage. + * + * <pre> + * // Create a simple index. "Item" is assumed to be an application + * // defined type that the application's UI and other processing knows about, + * // and that has a name. + * + * UErrorCode status = U_ZERO_ERROR; + * AlphabeticIndex index = new AlphabeticIndex(desiredLocale, status); + * index->addLabels(additionalLocale, status); + * for (Item *item in some source of Items ) { + * index->addRecord(item->name(), item, status); + * } + * ... + * // Show index at top. We could skip or gray out empty buckets + * + * while (index->nextBucket(status)) { + * if (showAll || index->getBucketRecordCount() != 0) { + * showLabelAtTop(UI, index->getBucketLabel()); + * } + * } + * ... + * // Show the buckets with their contents, skipping empty buckets + * + * index->resetBucketIterator(status); + * while (index->nextBucket(status)) { + * if (index->getBucketRecordCount() != 0) { + * showLabelInList(UI, index->getBucketLabel()); + * while (index->nextRecord(status)) { + * showIndexedItem(UI, static_cast<Item *>(index->getRecordData())) + * </pre> + * + * The caller can build different UIs using this class. + * For example, an index character could be omitted or grayed-out + * if its bucket is empty. Small buckets could also be combined based on size, such as: + * + * <pre> + * <b>... A-F G-N O-Z ...</b> + * </pre> + * + * <h2>Client Support</h2> + * <p>Callers can also use the AlphabeticIndex::ImmutableIndex, or the AlphabeticIndex itself, + * to support sorting on a client that doesn't support AlphabeticIndex functionality. + * + * <p>The ImmutableIndex is both immutable and thread-safe. + * The corresponding AlphabeticIndex methods are not thread-safe because + * they "lazily" build the index buckets. + * <ul> + * <li>ImmutableIndex.getBucket(index) provides random access to all + * buckets and their labels and label types. + * <li>The AlphabeticIndex bucket iterator or ImmutableIndex.getBucket(0..getBucketCount-1) + * can be used to get a list of the labels, + * such as "...", "A", "B",..., and send that list to the client. + * <li>When the client has a new name, it sends that name to the server. + * The server needs to call the following methods, + * and communicate the bucketIndex and collationKey back to the client. + * + * <pre> + * int32_t bucketIndex = index.getBucketIndex(name, status); + * const UnicodeString &label = immutableIndex.getBucket(bucketIndex)->getLabel(); // optional + * int32_t skLength = collator.getSortKey(name, sk, skCapacity); + * </pre> + * + * <li>The client would put the name (and associated information) into its bucket for bucketIndex. The sort key sk is a + * sequence of bytes that can be compared with a binary compare, and produce the right localized result.</li> + * </ul> + * + * @stable ICU 4.8 + */ +class U_I18N_API AlphabeticIndex: public UObject { +public: + /** + * An index "bucket" with a label string and type. + * It is referenced by getBucketIndex(), + * and returned by ImmutableIndex.getBucket(). + * + * The Bucket class is not intended for public subclassing. + * @stable ICU 51 + */ + class U_I18N_API Bucket : public UObject { + public: + /** + * Destructor. + * @stable ICU 51 + */ + virtual ~Bucket(); + + /** + * Returns the label string. + * + * @return the label string for the bucket + * @stable ICU 51 + */ + const UnicodeString &getLabel() const { return label_; } + /** + * Returns whether this bucket is a normal, underflow, overflow, or inflow bucket. + * + * @return the bucket label type + * @stable ICU 51 + */ + UAlphabeticIndexLabelType getLabelType() const { return labelType_; } + + private: + friend class AlphabeticIndex; + friend class BucketList; + + UnicodeString label_; + UnicodeString lowerBoundary_; + UAlphabeticIndexLabelType labelType_; + Bucket *displayBucket_; + int32_t displayIndex_; + UVector *records_; // Records are owned by the inputList_ vector. + + Bucket(const UnicodeString &label, // Parameter strings are copied. + const UnicodeString &lowerBoundary, + UAlphabeticIndexLabelType type); + }; + + /** + * Immutable, thread-safe version of AlphabeticIndex. + * This class provides thread-safe methods for bucketing, + * and random access to buckets and their properties, + * but does not offer adding records to the index. + * + * The ImmutableIndex class is not intended for public subclassing. + * + * @stable ICU 51 + */ + class U_I18N_API ImmutableIndex : public UObject { + public: + /** + * Destructor. + * @stable ICU 51 + */ + virtual ~ImmutableIndex(); + + /** + * Returns the number of index buckets and labels, including underflow/inflow/overflow. + * + * @return the number of index buckets + * @stable ICU 51 + */ + int32_t getBucketCount() const; + + /** + * Finds the index bucket for the given name and returns the number of that bucket. + * Use getBucket() to get the bucket's properties. + * + * @param name the string to be sorted into an index bucket + * @param errorCode Error code, will be set with the reason if the + * operation fails. + * @return the bucket number for the name + * @stable ICU 51 + */ + int32_t getBucketIndex(const UnicodeString &name, UErrorCode &errorCode) const; + + /** + * Returns the index-th bucket. Returns nullptr if the index is out of range. + * + * @param index bucket number + * @return the index-th bucket + * @stable ICU 51 + */ + const Bucket *getBucket(int32_t index) const; + + private: + friend class AlphabeticIndex; + + ImmutableIndex(BucketList *bucketList, Collator *collatorPrimaryOnly) + : buckets_(bucketList), collatorPrimaryOnly_(collatorPrimaryOnly) {} + + BucketList *buckets_; + Collator *collatorPrimaryOnly_; + }; + + /** + * Construct an AlphabeticIndex object for the specified locale. If the locale's + * data does not include index characters, a set of them will be + * synthesized based on the locale's exemplar characters. The locale + * determines the sorting order for both the index characters and the + * user item names appearing under each Index character. + * + * @param locale the desired locale. + * @param status Error code, will be set with the reason if the construction + * of the AlphabeticIndex object fails. + * @stable ICU 4.8 + */ + AlphabeticIndex(const Locale &locale, UErrorCode &status); + + /** + * Construct an AlphabeticIndex that uses a specific collator. + * + * The index will be created with no labels; the addLabels() function must be called + * after creation to add the desired labels to the index. + * + * The index adopts the collator, and is responsible for deleting it. + * The caller should make no further use of the collator after creating the index. + * + * @param collator The collator to use to order the contents of this index. + * @param status Error code, will be set with the reason if the + * operation fails. + * @stable ICU 51 + */ + AlphabeticIndex(RuleBasedCollator *collator, UErrorCode &status); + + /** + * Add Labels to this Index. The labels are additions to those + * that are already in the index; they do not replace the existing + * ones. + * @param additions The additional characters to add to the index, such as A-Z. + * @param status Error code, will be set with the reason if the + * operation fails. + * @return this, for chaining + * @stable ICU 4.8 + */ + virtual AlphabeticIndex &addLabels(const UnicodeSet &additions, UErrorCode &status); + + /** + * Add the index characters from a Locale to the index. The labels + * are added to those that are already in the index; they do not replace the + * existing index characters. The collation order for this index is not + * changed; it remains that of the locale that was originally specified + * when creating this Index. + * + * @param locale The locale whose index characters are to be added. + * @param status Error code, will be set with the reason if the + * operation fails. + * @return this, for chaining + * @stable ICU 4.8 + */ + virtual AlphabeticIndex &addLabels(const Locale &locale, UErrorCode &status); + + /** + * Destructor + * @stable ICU 4.8 + */ + virtual ~AlphabeticIndex(); + + /** + * Builds an immutable, thread-safe version of this instance, without data records. + * + * @return an immutable index instance + * @stable ICU 51 + */ + ImmutableIndex *buildImmutableIndex(UErrorCode &errorCode); + + /** + * Get the Collator that establishes the ordering of the items in this index. + * Ownership of the collator remains with the AlphabeticIndex instance. + * + * The returned collator is a reference to the internal collator used by this + * index. It may be safely used to compare the names of items or to get + * sort keys for names. However if any settings need to be changed, + * or other non-const methods called, a cloned copy must be made first. + * + * @return The collator + * @stable ICU 4.8 + */ + virtual const RuleBasedCollator &getCollator() const; + + + /** + * Get the default label used for abbreviated buckets *between* other index characters. + * For example, consider the labels when Latin (X Y Z) and Greek (Α Β Γ) are used: + * + * X Y Z ... Α Β Γ. + * + * @return inflow label + * @stable ICU 4.8 + */ + virtual const UnicodeString &getInflowLabel() const; + + /** + * Set the default label used for abbreviated buckets <i>between</i> other index characters. + * An inflow label will be automatically inserted if two otherwise-adjacent label characters + * are from different scripts, e.g. Latin and Cyrillic, and a third script, e.g. Greek, + * sorts between the two. The default inflow character is an ellipsis (...) + * + * @param inflowLabel the new Inflow label. + * @param status Error code, will be set with the reason if the operation fails. + * @return this + * @stable ICU 4.8 + */ + virtual AlphabeticIndex &setInflowLabel(const UnicodeString &inflowLabel, UErrorCode &status); + + + /** + * Get the special label used for items that sort after the last normal label, + * and that would not otherwise have an appropriate label. + * + * @return the overflow label + * @stable ICU 4.8 + */ + virtual const UnicodeString &getOverflowLabel() const; + + + /** + * Set the label used for items that sort after the last normal label, + * and that would not otherwise have an appropriate label. + * + * @param overflowLabel the new overflow label. + * @param status Error code, will be set with the reason if the operation fails. + * @return this + * @stable ICU 4.8 + */ + virtual AlphabeticIndex &setOverflowLabel(const UnicodeString &overflowLabel, UErrorCode &status); + + /** + * Get the special label used for items that sort before the first normal label, + * and that would not otherwise have an appropriate label. + * + * @return underflow label + * @stable ICU 4.8 + */ + virtual const UnicodeString &getUnderflowLabel() const; + + /** + * Set the label used for items that sort before the first normal label, + * and that would not otherwise have an appropriate label. + * + * @param underflowLabel the new underflow label. + * @param status Error code, will be set with the reason if the operation fails. + * @return this + * @stable ICU 4.8 + */ + virtual AlphabeticIndex &setUnderflowLabel(const UnicodeString &underflowLabel, UErrorCode &status); + + + /** + * Get the limit on the number of labels permitted in the index. + * The number does not include over, under and inflow labels. + * + * @return maxLabelCount maximum number of labels. + * @stable ICU 4.8 + */ + virtual int32_t getMaxLabelCount() const; + + /** + * Set a limit on the number of labels permitted in the index. + * The number does not include over, under and inflow labels. + * Currently, if the number is exceeded, then every + * nth item is removed to bring the count down. + * A more sophisticated mechanism may be available in the future. + * + * @param maxLabelCount the maximum number of labels. + * @param status error code + * @return This, for chaining + * @stable ICU 4.8 + */ + virtual AlphabeticIndex &setMaxLabelCount(int32_t maxLabelCount, UErrorCode &status); + + + /** + * Add a record to the index. Each record will be associated with an index Bucket + * based on the record's name. The list of records for each bucket will be sorted + * based on the collation ordering of the names in the index's locale. + * Records with duplicate names are permitted; they will be kept in the order + * that they were added. + * + * @param name The display name for the Record. The Record will be placed in + * a bucket based on this name. + * @param data An optional pointer to user data associated with this + * item. When iterating the contents of a bucket, both the + * data pointer the name will be available for each Record. + * @param status Error code, will be set with the reason if the operation fails. + * @return This, for chaining. + * @stable ICU 4.8 + */ + virtual AlphabeticIndex &addRecord(const UnicodeString &name, const void *data, UErrorCode &status); + + /** + * Remove all Records from the Index. The set of Buckets, which define the headings under + * which records are classified, is not altered. + * + * @param status Error code, will be set with the reason if the operation fails. + * @return This, for chaining. + * @stable ICU 4.8 + */ + virtual AlphabeticIndex &clearRecords(UErrorCode &status); + + + /** Get the number of labels in this index. + * Note: may trigger lazy index construction. + * + * @param status Error code, will be set with the reason if the operation fails. + * @return The number of labels in this index, including any under, over or + * in-flow labels. + * @stable ICU 4.8 + */ + virtual int32_t getBucketCount(UErrorCode &status); + + + /** Get the total number of Records in this index, that is, the number + * of <name, data> pairs added. + * + * @param status Error code, will be set with the reason if the operation fails. + * @return The number of records in this index, that is, the total number + * of (name, data) items added with addRecord(). + * @stable ICU 4.8 + */ + virtual int32_t getRecordCount(UErrorCode &status); + + + + /** + * Given the name of a record, return the zero-based index of the Bucket + * in which the item should appear. The name need not be in the index. + * A Record will not be added to the index by this function. + * Bucket numbers are zero-based, in Bucket iteration order. + * + * @param itemName The name whose bucket position in the index is to be determined. + * @param status Error code, will be set with the reason if the operation fails. + * @return The bucket number for this name. + * @stable ICU 4.8 + * + */ + virtual int32_t getBucketIndex(const UnicodeString &itemName, UErrorCode &status); + + + /** + * Get the zero based index of the current Bucket from an iteration + * over the Buckets of this index. Return -1 if no iteration is in process. + * @return the index of the current Bucket + * @stable ICU 4.8 + */ + virtual int32_t getBucketIndex() const; + + + /** + * Advance the iteration over the Buckets of this index. Return false if + * there are no more Buckets. + * + * @param status Error code, will be set with the reason if the operation fails. + * U_ENUM_OUT_OF_SYNC_ERROR will be reported if the index is modified while + * an enumeration of its contents are in process. + * + * @return true if success, false if at end of iteration + * @stable ICU 4.8 + */ + virtual UBool nextBucket(UErrorCode &status); + + /** + * Return the name of the Label of the current bucket from an iteration over the buckets. + * If the iteration is before the first Bucket (nextBucket() has not been called), + * or after the last, return an empty string. + * + * @return the bucket label. + * @stable ICU 4.8 + */ + virtual const UnicodeString &getBucketLabel() const; + + /** + * Return the type of the label for the current Bucket (selected by the + * iteration over Buckets.) + * + * @return the label type. + * @stable ICU 4.8 + */ + virtual UAlphabeticIndexLabelType getBucketLabelType() const; + + /** + * Get the number of <name, data> Records in the current Bucket. + * If the current bucket iteration position is before the first label or after the + * last, return 0. + * + * @return the number of Records. + * @stable ICU 4.8 + */ + virtual int32_t getBucketRecordCount() const; + + + /** + * Reset the Bucket iteration for this index. The next call to nextBucket() + * will restart the iteration at the first label. + * + * @param status Error code, will be set with the reason if the operation fails. + * @return this, for chaining. + * @stable ICU 4.8 + */ + virtual AlphabeticIndex &resetBucketIterator(UErrorCode &status); + + /** + * Advance to the next record in the current Bucket. + * When nextBucket() is called, Record iteration is reset to just before the + * first Record in the new Bucket. + * + * @param status Error code, will be set with the reason if the operation fails. + * U_ENUM_OUT_OF_SYNC_ERROR will be reported if the index is modified while + * an enumeration of its contents are in process. + * @return true if successful, false when the iteration advances past the last item. + * @stable ICU 4.8 + */ + virtual UBool nextRecord(UErrorCode &status); + + /** + * Get the name of the current Record. + * Return an empty string if the Record iteration position is before first + * or after the last. + * + * @return The name of the current index item. + * @stable ICU 4.8 + */ + virtual const UnicodeString &getRecordName() const; + + + /** + * Return the data pointer of the Record currently being iterated over. + * Return nullptr if the current iteration position before the first item in this Bucket, + * or after the last. + * + * @return The current Record's data pointer. + * @stable ICU 4.8 + */ + virtual const void *getRecordData() const; + + + /** + * Reset the Record iterator position to before the first Record in the current Bucket. + * + * @return This, for chaining. + * @stable ICU 4.8 + */ + virtual AlphabeticIndex &resetRecordIterator(); + +private: + /** + * No Copy constructor. + * @internal (private) + */ + AlphabeticIndex(const AlphabeticIndex &other) = delete; + + /** + * No assignment. + */ + AlphabeticIndex &operator =(const AlphabeticIndex & /*other*/) { return *this;} + + /** + * No Equality operators. + * @internal (private) + */ + virtual bool operator==(const AlphabeticIndex& other) const; + + /** + * Inequality operator. + * @internal (private) + */ + virtual bool operator!=(const AlphabeticIndex& other) const; + + // Common initialization, for use from all constructors. + void init(const Locale *locale, UErrorCode &status); + + /** + * This method is called to get the index exemplars. Normally these come from the locale directly, + * but if they aren't available, we have to synthesize them. + */ + void addIndexExemplars(const Locale &locale, UErrorCode &status); + /** + * Add Chinese index characters from the tailoring. + */ + UBool addChineseIndexCharacters(UErrorCode &errorCode); + + UVector *firstStringsInScript(UErrorCode &status); + + static UnicodeString separated(const UnicodeString &item); + + /** + * Determine the best labels to use. + * This is based on the exemplars, but we also process to make sure that they are unique, + * and sort differently, and that the overall list is small enough. + */ + void initLabels(UVector &indexCharacters, UErrorCode &errorCode) const; + BucketList *createBucketList(UErrorCode &errorCode) const; + void initBuckets(UErrorCode &errorCode); + void clearBuckets(); + void internalResetBucketIterator(); + +public: + + // The Record is declared public only to allow access from + // implementation code written in plain C. + // It is not intended for public use. + +#ifndef U_HIDE_INTERNAL_API + /** + * A (name, data) pair, to be sorted by name into one of the index buckets. + * The user data is not used by the index implementation. + * \cond + * @internal + */ + struct Record: public UMemory { + const UnicodeString name_; + const void *data_; + Record(const UnicodeString &name, const void *data); + ~Record(); + }; + /** \endcond */ +#endif /* U_HIDE_INTERNAL_API */ + +private: + + /** + * Holds all user records before they are distributed into buckets. + * Type of contents is (Record *) + * @internal (private) + */ + UVector *inputList_; + + int32_t labelsIterIndex_; // Index of next item to return. + int32_t itemsIterIndex_; + Bucket *currentBucket_; // While an iteration of the index in underway, + // point to the bucket for the current label. + // nullptr when no iteration underway. + + int32_t maxLabelCount_; // Limit on # of labels permitted in the index. + + UnicodeSet *initialLabels_; // Initial (unprocessed) set of Labels. Union + // of those explicitly set by the user plus + // those from locales. Raw values, before + // crunching into bucket labels. + + UVector *firstCharsInScripts_; // The first character from each script, + // in collation order. + + RuleBasedCollator *collator_; + RuleBasedCollator *collatorPrimaryOnly_; + + // Lazy evaluated: null means that we have not built yet. + BucketList *buckets_; + + UnicodeString inflowLabel_; + UnicodeString overflowLabel_; + UnicodeString underflowLabel_; + UnicodeString overflowComparisonString_; + + UnicodeString emptyString_; +}; + +U_NAMESPACE_END + +#endif // !UCONFIG_NO_COLLATION + +#endif /* U_SHOW_CPLUSPLUS_API */ + +#endif |