summaryrefslogtreecommitdiffstats
path: root/intl/icu/source/i18n/unicode/search.h
diff options
context:
space:
mode:
authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 19:33:14 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 19:33:14 +0000
commit36d22d82aa202bb199967e9512281e9a53db42c9 (patch)
tree105e8c98ddea1c1e4784a60a5a6410fa416be2de /intl/icu/source/i18n/unicode/search.h
parentInitial commit. (diff)
downloadfirefox-esr-upstream.tar.xz
firefox-esr-upstream.zip
Adding upstream version 115.7.0esr.upstream/115.7.0esrupstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to '')
-rw-r--r--intl/icu/source/i18n/unicode/search.h580
1 files changed, 580 insertions, 0 deletions
diff --git a/intl/icu/source/i18n/unicode/search.h b/intl/icu/source/i18n/unicode/search.h
new file mode 100644
index 0000000000..a8004efc43
--- /dev/null
+++ b/intl/icu/source/i18n/unicode/search.h
@@ -0,0 +1,580 @@
+// © 2016 and later: Unicode, Inc. and others.
+// License & terms of use: http://www.unicode.org/copyright.html
+/*
+**********************************************************************
+* Copyright (C) 2001-2011 IBM and others. All rights reserved.
+**********************************************************************
+* Date Name Description
+* 03/22/2000 helena Creation.
+**********************************************************************
+*/
+
+#ifndef SEARCH_H
+#define SEARCH_H
+
+#include "unicode/utypes.h"
+
+#if U_SHOW_CPLUSPLUS_API
+
+/**
+ * \file
+ * \brief C++ API: SearchIterator object.
+ */
+
+#if !UCONFIG_NO_COLLATION && !UCONFIG_NO_BREAK_ITERATION
+
+#include "unicode/uobject.h"
+#include "unicode/unistr.h"
+#include "unicode/chariter.h"
+#include "unicode/brkiter.h"
+#include "unicode/usearch.h"
+
+/**
+* @stable ICU 2.0
+*/
+struct USearch;
+/**
+* @stable ICU 2.0
+*/
+typedef struct USearch USearch;
+
+U_NAMESPACE_BEGIN
+
+/**
+ *
+ * <tt>SearchIterator</tt> is an abstract base class that provides
+ * methods to search for a pattern within a text string. Instances of
+ * <tt>SearchIterator</tt> maintain a current position and scans over the
+ * target text, returning the indices the pattern is matched and the length
+ * of each match.
+ * <p>
+ * <tt>SearchIterator</tt> defines a protocol for text searching.
+ * Subclasses provide concrete implementations of various search algorithms.
+ * For example, <tt>StringSearch</tt> implements language-sensitive pattern
+ * matching based on the comparison rules defined in a
+ * <tt>RuleBasedCollator</tt> object.
+ * <p>
+ * Other options for searching includes using a BreakIterator to restrict
+ * the points at which matches are detected.
+ * <p>
+ * <tt>SearchIterator</tt> provides an API that is similar to that of
+ * other text iteration classes such as <tt>BreakIterator</tt>. Using
+ * this class, it is easy to scan through text looking for all occurrences of
+ * a given pattern. The following example uses a <tt>StringSearch</tt>
+ * object to find all instances of "fox" in the target string. Any other
+ * subclass of <tt>SearchIterator</tt> can be used in an identical
+ * manner.
+ * <pre><code>
+ * UnicodeString target("The quick brown fox jumped over the lazy fox");
+ * UnicodeString pattern("fox");
+ *
+ * SearchIterator *iter = new StringSearch(pattern, target);
+ * UErrorCode error = U_ZERO_ERROR;
+ * for (int pos = iter->first(error); pos != USEARCH_DONE;
+ * pos = iter->next(error)) {
+ * printf("Found match at %d pos, length is %d\n", pos, iter.getMatchedLength());
+ * }
+ * </code></pre>
+ *
+ * @see StringSearch
+ * @see RuleBasedCollator
+ */
+class U_I18N_API SearchIterator : public UObject {
+
+public:
+
+ // public constructors and destructors -------------------------------
+
+ /**
+ * Copy constructor that creates a SearchIterator instance with the same
+ * behavior, and iterating over the same text.
+ * @param other the SearchIterator instance to be copied.
+ * @stable ICU 2.0
+ */
+ SearchIterator(const SearchIterator &other);
+
+ /**
+ * Destructor. Cleans up the search iterator data struct.
+ * @stable ICU 2.0
+ */
+ virtual ~SearchIterator();
+
+ // public get and set methods ----------------------------------------
+
+ /**
+ * Sets the index to point to the given position, and clears any state
+ * that's affected.
+ * <p>
+ * This method takes the argument index and sets the position in the text
+ * string accordingly without checking if the index is pointing to a
+ * valid starting point to begin searching.
+ * @param position within the text to be set. If position is less
+ * than or greater than the text range for searching,
+ * an U_INDEX_OUTOFBOUNDS_ERROR will be returned
+ * @param status for errors if it occurs
+ * @stable ICU 2.0
+ */
+ virtual void setOffset(int32_t position, UErrorCode &status) = 0;
+
+ /**
+ * Return the current index in the text being searched.
+ * If the iteration has gone past the end of the text
+ * (or past the beginning for a backwards search), USEARCH_DONE
+ * is returned.
+ * @return current index in the text being searched.
+ * @stable ICU 2.0
+ */
+ virtual int32_t getOffset(void) const = 0;
+
+ /**
+ * Sets the text searching attributes located in the enum
+ * USearchAttribute with values from the enum USearchAttributeValue.
+ * USEARCH_DEFAULT can be used for all attributes for resetting.
+ * @param attribute text attribute (enum USearchAttribute) to be set
+ * @param value text attribute value
+ * @param status for errors if it occurs
+ * @stable ICU 2.0
+ */
+ void setAttribute(USearchAttribute attribute,
+ USearchAttributeValue value,
+ UErrorCode &status);
+
+ /**
+ * Gets the text searching attributes
+ * @param attribute text attribute (enum USearchAttribute) to be retrieve
+ * @return text attribute value
+ * @stable ICU 2.0
+ */
+ USearchAttributeValue getAttribute(USearchAttribute attribute) const;
+
+ /**
+ * Returns the index to the match in the text string that was searched.
+ * This call returns a valid result only after a successful call to
+ * <tt>first</tt>, <tt>next</tt>, <tt>previous</tt>, or <tt>last</tt>.
+ * Just after construction, or after a searching method returns
+ * <tt>USEARCH_DONE</tt>, this method will return <tt>USEARCH_DONE</tt>.
+ * <p>
+ * Use getMatchedLength to get the matched string length.
+ * @return index of a substring within the text string that is being
+ * searched.
+ * @see #first
+ * @see #next
+ * @see #previous
+ * @see #last
+ * @stable ICU 2.0
+ */
+ int32_t getMatchedStart(void) const;
+
+ /**
+ * Returns the length of text in the string which matches the search
+ * pattern. This call returns a valid result only after a successful call
+ * to <tt>first</tt>, <tt>next</tt>, <tt>previous</tt>, or <tt>last</tt>.
+ * Just after construction, or after a searching method returns
+ * <tt>USEARCH_DONE</tt>, this method will return 0.
+ * @return The length of the match in the target text, or 0 if there
+ * is no match currently.
+ * @see #first
+ * @see #next
+ * @see #previous
+ * @see #last
+ * @stable ICU 2.0
+ */
+ int32_t getMatchedLength(void) const;
+
+ /**
+ * Returns the text that was matched by the most recent call to
+ * <tt>first</tt>, <tt>next</tt>, <tt>previous</tt>, or <tt>last</tt>.
+ * If the iterator is not pointing at a valid match (e.g. just after
+ * construction or after <tt>USEARCH_DONE</tt> has been returned,
+ * returns an empty string.
+ * @param result stores the matched string or an empty string if a match
+ * is not found.
+ * @see #first
+ * @see #next
+ * @see #previous
+ * @see #last
+ * @stable ICU 2.0
+ */
+ void getMatchedText(UnicodeString &result) const;
+
+ /**
+ * Set the BreakIterator that will be used to restrict the points
+ * at which matches are detected. The user is responsible for deleting
+ * the breakiterator.
+ * @param breakiter A BreakIterator that will be used to restrict the
+ * points at which matches are detected. If a match is
+ * found, but the match's start or end index is not a
+ * boundary as determined by the <tt>BreakIterator</tt>,
+ * the match will be rejected and another will be searched
+ * for. If this parameter is <tt>nullptr</tt>, no break
+ * detection is attempted.
+ * @param status for errors if it occurs
+ * @see BreakIterator
+ * @stable ICU 2.0
+ */
+ void setBreakIterator(BreakIterator *breakiter, UErrorCode &status);
+
+ /**
+ * Returns the BreakIterator that is used to restrict the points at
+ * which matches are detected. This will be the same object that was
+ * passed to the constructor or to <tt>setBreakIterator</tt>.
+ * Note that <tt>nullptr</tt> is a legal value; it means that break
+ * detection should not be attempted.
+ * @return BreakIterator used to restrict matchings.
+ * @see #setBreakIterator
+ * @stable ICU 2.0
+ */
+ const BreakIterator * getBreakIterator(void) const;
+
+ /**
+ * Set the string text to be searched. Text iteration will hence begin at
+ * the start of the text string. This method is useful if you want to
+ * re-use an iterator to search for the same pattern within a different
+ * body of text. The user is responsible for deleting the text.
+ * @param text string to be searched.
+ * @param status for errors. If the text length is 0,
+ * an U_ILLEGAL_ARGUMENT_ERROR is returned.
+ * @stable ICU 2.0
+ */
+ virtual void setText(const UnicodeString &text, UErrorCode &status);
+
+ /**
+ * Set the string text to be searched. Text iteration will hence begin at
+ * the start of the text string. This method is useful if you want to
+ * re-use an iterator to search for the same pattern within a different
+ * body of text.
+ * <p>
+ * Note: No parsing of the text within the <tt>CharacterIterator</tt>
+ * will be done during searching for this version. The block of text
+ * in <tt>CharacterIterator</tt> will be used as it is.
+ * The user is responsible for deleting the text.
+ * @param text string iterator to be searched.
+ * @param status for errors if any. If the text length is 0 then an
+ * U_ILLEGAL_ARGUMENT_ERROR is returned.
+ * @stable ICU 2.0
+ */
+ virtual void setText(CharacterIterator &text, UErrorCode &status);
+
+ /**
+ * Return the string text to be searched.
+ * @return text string to be searched.
+ * @stable ICU 2.0
+ */
+ const UnicodeString & getText(void) const;
+
+ // operator overloading ----------------------------------------------
+
+ /**
+ * Equality operator.
+ * @param that SearchIterator instance to be compared.
+ * @return true if both BreakIterators are of the same class, have the
+ * same behavior, terates over the same text and have the same
+ * attributes. false otherwise.
+ * @stable ICU 2.0
+ */
+ virtual bool operator==(const SearchIterator &that) const;
+
+ /**
+ * Not-equal operator.
+ * @param that SearchIterator instance to be compared.
+ * @return false if operator== returns true, and vice versa.
+ * @stable ICU 2.0
+ */
+ bool operator!=(const SearchIterator &that) const;
+
+ // public methods ----------------------------------------------------
+
+ /**
+ * Returns a copy of SearchIterator with the same behavior, and
+ * iterating over the same text, as this one. Note that all data will be
+ * replicated, except for the text string to be searched.
+ * @return cloned object
+ * @stable ICU 2.0
+ */
+ virtual SearchIterator* safeClone(void) const = 0;
+
+ /**
+ * Returns the first index at which the string text matches the search
+ * pattern. The iterator is adjusted so that its current index (as
+ * returned by <tt>getOffset</tt>) is the match position if one
+ * was found.
+ * If a match is not found, <tt>USEARCH_DONE</tt> will be returned and
+ * the iterator will be adjusted to the index USEARCH_DONE
+ * @param status for errors if it occurs
+ * @return The character index of the first match, or
+ * <tt>USEARCH_DONE</tt> if there are no matches.
+ * @see #getOffset
+ * @stable ICU 2.0
+ */
+ int32_t first(UErrorCode &status);
+
+ /**
+ * Returns the first index equal or greater than <tt>position</tt> at which the
+ * string text matches the search pattern. The iterator is adjusted so
+ * that its current index (as returned by <tt>getOffset</tt>) is the
+ * match position if one was found.
+ * If a match is not found, <tt>USEARCH_DONE</tt> will be returned and the
+ * iterator will be adjusted to the index <tt>USEARCH_DONE</tt>.
+ * @param position where search if to start from. If position is less
+ * than or greater than the text range for searching,
+ * an U_INDEX_OUTOFBOUNDS_ERROR will be returned
+ * @param status for errors if it occurs
+ * @return The character index of the first match following
+ * <tt>position</tt>, or <tt>USEARCH_DONE</tt> if there are no
+ * matches.
+ * @see #getOffset
+ * @stable ICU 2.0
+ */
+ int32_t following(int32_t position, UErrorCode &status);
+
+ /**
+ * Returns the last index in the target text at which it matches the
+ * search pattern. The iterator is adjusted so that its current index
+ * (as returned by <tt>getOffset</tt>) is the match position if one was
+ * found.
+ * If a match is not found, <tt>USEARCH_DONE</tt> will be returned and
+ * the iterator will be adjusted to the index USEARCH_DONE.
+ * @param status for errors if it occurs
+ * @return The index of the first match, or <tt>USEARCH_DONE</tt> if
+ * there are no matches.
+ * @see #getOffset
+ * @stable ICU 2.0
+ */
+ int32_t last(UErrorCode &status);
+
+ /**
+ * Returns the first index less than <tt>position</tt> at which the string
+ * text matches the search pattern. The iterator is adjusted so that its
+ * current index (as returned by <tt>getOffset</tt>) is the match
+ * position if one was found. If a match is not found,
+ * <tt>USEARCH_DONE</tt> will be returned and the iterator will be
+ * adjusted to the index USEARCH_DONE
+ * <p>
+ * When <tt>USEARCH_OVERLAP</tt> option is off, the last index of the
+ * result match is always less than <tt>position</tt>.
+ * When <tt>USERARCH_OVERLAP</tt> is on, the result match may span across
+ * <tt>position</tt>.
+ *
+ * @param position where search is to start from. If position is less
+ * than or greater than the text range for searching,
+ * an U_INDEX_OUTOFBOUNDS_ERROR will be returned
+ * @param status for errors if it occurs
+ * @return The character index of the first match preceding
+ * <tt>position</tt>, or <tt>USEARCH_DONE</tt> if there are
+ * no matches.
+ * @see #getOffset
+ * @stable ICU 2.0
+ */
+ int32_t preceding(int32_t position, UErrorCode &status);
+
+ /**
+ * Returns the index of the next point at which the text matches the
+ * search pattern, starting from the current position
+ * The iterator is adjusted so that its current index (as returned by
+ * <tt>getOffset</tt>) is the match position if one was found.
+ * If a match is not found, <tt>USEARCH_DONE</tt> will be returned and
+ * the iterator will be adjusted to a position after the end of the text
+ * string.
+ * @param status for errors if it occurs
+ * @return The index of the next match after the current position,
+ * or <tt>USEARCH_DONE</tt> if there are no more matches.
+ * @see #getOffset
+ * @stable ICU 2.0
+ */
+ int32_t next(UErrorCode &status);
+
+ /**
+ * Returns the index of the previous point at which the string text
+ * matches the search pattern, starting at the current position.
+ * The iterator is adjusted so that its current index (as returned by
+ * <tt>getOffset</tt>) is the match position if one was found.
+ * If a match is not found, <tt>USEARCH_DONE</tt> will be returned and
+ * the iterator will be adjusted to the index USEARCH_DONE
+ * @param status for errors if it occurs
+ * @return The index of the previous match before the current position,
+ * or <tt>USEARCH_DONE</tt> if there are no more matches.
+ * @see #getOffset
+ * @stable ICU 2.0
+ */
+ int32_t previous(UErrorCode &status);
+
+ /**
+ * Resets the iteration.
+ * Search will begin at the start of the text string if a forward
+ * iteration is initiated before a backwards iteration. Otherwise if a
+ * backwards iteration is initiated before a forwards iteration, the
+ * search will begin at the end of the text string.
+ * @stable ICU 2.0
+ */
+ virtual void reset();
+
+protected:
+ // protected data members ---------------------------------------------
+
+ /**
+ * C search data struct
+ * @stable ICU 2.0
+ */
+ USearch *m_search_;
+
+ /**
+ * Break iterator.
+ * Currently the C++ breakiterator does not have getRules etc to reproduce
+ * another in C. Hence we keep the original around and do the verification
+ * at the end of the match. The user is responsible for deleting this
+ * break iterator.
+ * @stable ICU 2.0
+ */
+ BreakIterator *m_breakiterator_;
+
+ /**
+ * Unicode string version of the search text
+ * @stable ICU 2.0
+ */
+ UnicodeString m_text_;
+
+ // protected constructors and destructors -----------------------------
+
+ /**
+ * Default constructor.
+ * Initializes data to the default values.
+ * @stable ICU 2.0
+ */
+ SearchIterator();
+
+ /**
+ * Constructor for use by subclasses.
+ * @param text The target text to be searched.
+ * @param breakiter A {@link BreakIterator} that is used to restrict the
+ * points at which matches are detected. If
+ * <tt>handleNext</tt> or <tt>handlePrev</tt> finds a
+ * match, but the match's start or end index is not a
+ * boundary as determined by the <tt>BreakIterator</tt>,
+ * the match is rejected and <tt>handleNext</tt> or
+ * <tt>handlePrev</tt> is called again. If this parameter
+ * is <tt>nullptr</tt>, no break detection is attempted.
+ * @see #handleNext
+ * @see #handlePrev
+ * @stable ICU 2.0
+ */
+ SearchIterator(const UnicodeString &text,
+ BreakIterator *breakiter = nullptr);
+
+ /**
+ * Constructor for use by subclasses.
+ * <p>
+ * Note: No parsing of the text within the <tt>CharacterIterator</tt>
+ * will be done during searching for this version. The block of text
+ * in <tt>CharacterIterator</tt> will be used as it is.
+ * @param text The target text to be searched.
+ * @param breakiter A {@link BreakIterator} that is used to restrict the
+ * points at which matches are detected. If
+ * <tt>handleNext</tt> or <tt>handlePrev</tt> finds a
+ * match, but the match's start or end index is not a
+ * boundary as determined by the <tt>BreakIterator</tt>,
+ * the match is rejected and <tt>handleNext</tt> or
+ * <tt>handlePrev</tt> is called again. If this parameter
+ * is <tt>nullptr</tt>, no break detection is attempted.
+ * @see #handleNext
+ * @see #handlePrev
+ * @stable ICU 2.0
+ */
+ SearchIterator(CharacterIterator &text, BreakIterator *breakiter = nullptr);
+
+ // protected methods --------------------------------------------------
+
+ /**
+ * Assignment operator. Sets this iterator to have the same behavior,
+ * and iterate over the same text, as the one passed in.
+ * @param that instance to be copied.
+ * @stable ICU 2.0
+ */
+ SearchIterator & operator=(const SearchIterator &that);
+
+ /**
+ * Abstract method which subclasses override to provide the mechanism
+ * for finding the next match in the target text. This allows different
+ * subclasses to provide different search algorithms.
+ * <p>
+ * If a match is found, the implementation should return the index at
+ * which the match starts and should call
+ * <tt>setMatchLength</tt> with the number of characters
+ * in the target text that make up the match. If no match is found, the
+ * method should return USEARCH_DONE.
+ * <p>
+ * @param position The index in the target text at which the search
+ * should start.
+ * @param status for error codes if it occurs.
+ * @return index at which the match starts, else if match is not found
+ * USEARCH_DONE is returned
+ * @see #setMatchLength
+ * @stable ICU 2.0
+ */
+ virtual int32_t handleNext(int32_t position, UErrorCode &status)
+ = 0;
+
+ /**
+ * Abstract method which subclasses override to provide the mechanism for
+ * finding the previous match in the target text. This allows different
+ * subclasses to provide different search algorithms.
+ * <p>
+ * If a match is found, the implementation should return the index at
+ * which the match starts and should call
+ * <tt>setMatchLength</tt> with the number of characters
+ * in the target text that make up the match. If no match is found, the
+ * method should return USEARCH_DONE.
+ * <p>
+ * @param position The index in the target text at which the search
+ * should start.
+ * @param status for error codes if it occurs.
+ * @return index at which the match starts, else if match is not found
+ * USEARCH_DONE is returned
+ * @see #setMatchLength
+ * @stable ICU 2.0
+ */
+ virtual int32_t handlePrev(int32_t position, UErrorCode &status)
+ = 0;
+
+ /**
+ * Sets the length of the currently matched string in the text string to
+ * be searched.
+ * Subclasses' <tt>handleNext</tt> and <tt>handlePrev</tt>
+ * methods should call this when they find a match in the target text.
+ * @param length length of the matched text.
+ * @see #handleNext
+ * @see #handlePrev
+ * @stable ICU 2.0
+ */
+ virtual void setMatchLength(int32_t length);
+
+ /**
+ * Sets the offset of the currently matched string in the text string to
+ * be searched.
+ * Subclasses' <tt>handleNext</tt> and <tt>handlePrev</tt>
+ * methods should call this when they find a match in the target text.
+ * @param position start offset of the matched text.
+ * @see #handleNext
+ * @see #handlePrev
+ * @stable ICU 2.0
+ */
+ virtual void setMatchStart(int32_t position);
+
+ /**
+ * sets match not found
+ * @stable ICU 2.0
+ */
+ void setMatchNotFound();
+};
+
+inline bool SearchIterator::operator!=(const SearchIterator &that) const
+{
+ return !operator==(that);
+}
+U_NAMESPACE_END
+
+#endif /* #if !UCONFIG_NO_COLLATION */
+
+#endif /* U_SHOW_CPLUSPLUS_API */
+
+#endif
+