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1596 lines
66 KiB
1596 lines
66 KiB
// © 2016 and later: Unicode, Inc. and others.
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// License & terms of use: http://www.unicode.org/copyright.html
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/*
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**********************************************************************
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* Copyright (C) 1999-2014, International Business Machines
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* Corporation and others. All Rights Reserved.
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**********************************************************************
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* Date Name Description
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* 11/17/99 aliu Creation.
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**********************************************************************
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*/
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#ifndef TRANSLIT_H
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#define TRANSLIT_H
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#include "unicode/utypes.h"
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#if U_SHOW_CPLUSPLUS_API
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/**
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* \file
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* \brief C++ API: Tranforms text from one format to another.
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*/
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#if !UCONFIG_NO_TRANSLITERATION
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#include "unicode/uobject.h"
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#include "unicode/unistr.h"
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#include "unicode/parseerr.h"
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#include "unicode/utrans.h" // UTransPosition, UTransDirection
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#include "unicode/strenum.h"
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U_NAMESPACE_BEGIN
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class UnicodeFilter;
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class UnicodeSet;
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class TransliteratorParser;
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class NormalizationTransliterator;
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class TransliteratorIDParser;
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/**
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*
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* <code>Transliterator</code> is an abstract class that
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* transliterates text from one format to another. The most common
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* kind of transliterator is a script, or alphabet, transliterator.
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* For example, a Russian to Latin transliterator changes Russian text
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* written in Cyrillic characters to phonetically equivalent Latin
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* characters. It does not <em>translate</em> Russian to English!
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* Transliteration, unlike translation, operates on characters, without
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* reference to the meanings of words and sentences.
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*
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* <p>Although script conversion is its most common use, a
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* transliterator can actually perform a more general class of tasks.
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* In fact, <code>Transliterator</code> defines a very general API
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* which specifies only that a segment of the input text is replaced
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* by new text. The particulars of this conversion are determined
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* entirely by subclasses of <code>Transliterator</code>.
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*
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* <p><b>Transliterators are stateless</b>
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*
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* <p><code>Transliterator</code> objects are <em>stateless</em>; they
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* retain no information between calls to
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* <code>transliterate()</code>. (However, this does <em>not</em>
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* mean that threads may share transliterators without synchronizing
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* them. Transliterators are not immutable, so they must be
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* synchronized when shared between threads.) This might seem to
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* limit the complexity of the transliteration operation. In
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* practice, subclasses perform complex transliterations by delaying
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* the replacement of text until it is known that no other
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* replacements are possible. In other words, although the
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* <code>Transliterator</code> objects are stateless, the source text
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* itself embodies all the needed information, and delayed operation
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* allows arbitrary complexity.
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*
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* <p><b>Batch transliteration</b>
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*
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* <p>The simplest way to perform transliteration is all at once, on a
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* string of existing text. This is referred to as <em>batch</em>
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* transliteration. For example, given a string <code>input</code>
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* and a transliterator <code>t</code>, the call
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*
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* String result = t.transliterate(input);
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*
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* will transliterate it and return the result. Other methods allow
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* the client to specify a substring to be transliterated and to use
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* {@link Replaceable } objects instead of strings, in order to
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* preserve out-of-band information (such as text styles).
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*
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* <p><b>Keyboard transliteration</b>
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*
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* <p>Somewhat more involved is <em>keyboard</em>, or incremental
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* transliteration. This is the transliteration of text that is
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* arriving from some source (typically the user's keyboard) one
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* character at a time, or in some other piecemeal fashion.
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*
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* <p>In keyboard transliteration, a <code>Replaceable</code> buffer
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* stores the text. As text is inserted, as much as possible is
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* transliterated on the fly. This means a GUI that displays the
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* contents of the buffer may show text being modified as each new
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* character arrives.
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*
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* <p>Consider the simple rule-based Transliterator:
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* <pre>
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* th>{theta}
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* t>{tau}
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* </pre>
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*
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* When the user types 't', nothing will happen, since the
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* transliterator is waiting to see if the next character is 'h'. To
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* remedy this, we introduce the notion of a cursor, marked by a '|'
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* in the output string:
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* <pre>
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* t>|{tau}
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* {tau}h>{theta}
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* </pre>
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*
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* Now when the user types 't', tau appears, and if the next character
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* is 'h', the tau changes to a theta. This is accomplished by
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* maintaining a cursor position (independent of the insertion point,
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* and invisible in the GUI) across calls to
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* <code>transliterate()</code>. Typically, the cursor will
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* be coincident with the insertion point, but in a case like the one
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* above, it will precede the insertion point.
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*
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* <p>Keyboard transliteration methods maintain a set of three indices
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* that are updated with each call to
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* <code>transliterate()</code>, including the cursor, start,
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* and limit. Since these indices are changed by the method, they are
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* passed in an <code>int[]</code> array. The <code>START</code> index
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* marks the beginning of the substring that the transliterator will
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* look at. It is advanced as text becomes committed (but it is not
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* the committed index; that's the <code>CURSOR</code>). The
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* <code>CURSOR</code> index, described above, marks the point at
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* which the transliterator last stopped, either because it reached
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* the end, or because it required more characters to disambiguate
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* between possible inputs. The <code>CURSOR</code> can also be
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* explicitly set by rules in a rule-based Transliterator.
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* Any characters before the <code>CURSOR</code> index are frozen;
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* future keyboard transliteration calls within this input sequence
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* will not change them. New text is inserted at the
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* <code>LIMIT</code> index, which marks the end of the substring that
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* the transliterator looks at.
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*
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* <p>Because keyboard transliteration assumes that more characters
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* are to arrive, it is conservative in its operation. It only
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* transliterates when it can do so unambiguously. Otherwise it waits
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* for more characters to arrive. When the client code knows that no
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* more characters are forthcoming, perhaps because the user has
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* performed some input termination operation, then it should call
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* <code>finishTransliteration()</code> to complete any
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* pending transliterations.
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*
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* <p><b>Inverses</b>
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*
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* <p>Pairs of transliterators may be inverses of one another. For
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* example, if transliterator <b>A</b> transliterates characters by
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* incrementing their Unicode value (so "abc" -> "def"), and
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* transliterator <b>B</b> decrements character values, then <b>A</b>
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* is an inverse of <b>B</b> and vice versa. If we compose <b>A</b>
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* with <b>B</b> in a compound transliterator, the result is the
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* indentity transliterator, that is, a transliterator that does not
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* change its input text.
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*
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* The <code>Transliterator</code> method <code>getInverse()</code>
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* returns a transliterator's inverse, if one exists, or
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* <code>null</code> otherwise. However, the result of
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* <code>getInverse()</code> usually will <em>not</em> be a true
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* mathematical inverse. This is because true inverse transliterators
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* are difficult to formulate. For example, consider two
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* transliterators: <b>AB</b>, which transliterates the character 'A'
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* to 'B', and <b>BA</b>, which transliterates 'B' to 'A'. It might
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* seem that these are exact inverses, since
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*
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* \htmlonly<blockquote>\endhtmlonly"A" x <b>AB</b> -> "B"<br>
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* "B" x <b>BA</b> -> "A"\htmlonly</blockquote>\endhtmlonly
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*
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* where 'x' represents transliteration. However,
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*
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* \htmlonly<blockquote>\endhtmlonly"ABCD" x <b>AB</b> -> "BBCD"<br>
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* "BBCD" x <b>BA</b> -> "AACD"\htmlonly</blockquote>\endhtmlonly
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*
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* so <b>AB</b> composed with <b>BA</b> is not the
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* identity. Nonetheless, <b>BA</b> may be usefully considered to be
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* <b>AB</b>'s inverse, and it is on this basis that
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* <b>AB</b><code>.getInverse()</code> could legitimately return
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* <b>BA</b>.
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*
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* <p><b>IDs and display names</b>
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*
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* <p>A transliterator is designated by a short identifier string or
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* <em>ID</em>. IDs follow the format <em>source-destination</em>,
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* where <em>source</em> describes the entity being replaced, and
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* <em>destination</em> describes the entity replacing
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* <em>source</em>. The entities may be the names of scripts,
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* particular sequences of characters, or whatever else it is that the
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* transliterator converts to or from. For example, a transliterator
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* from Russian to Latin might be named "Russian-Latin". A
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* transliterator from keyboard escape sequences to Latin-1 characters
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* might be named "KeyboardEscape-Latin1". By convention, system
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* entity names are in English, with the initial letters of words
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* capitalized; user entity names may follow any format so long as
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* they do not contain dashes.
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*
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* <p>In addition to programmatic IDs, transliterator objects have
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* display names for presentation in user interfaces, returned by
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* {@link #getDisplayName }.
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*
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* <p><b>Factory methods and registration</b>
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*
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* <p>In general, client code should use the factory method
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* {@link #createInstance } to obtain an instance of a
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* transliterator given its ID. Valid IDs may be enumerated using
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* <code>getAvailableIDs()</code>. Since transliterators are mutable,
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* multiple calls to {@link #createInstance } with the same ID will
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* return distinct objects.
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*
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* <p>In addition to the system transliterators registered at startup,
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* user transliterators may be registered by calling
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* <code>registerInstance()</code> at run time. A registered instance
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* acts a template; future calls to {@link #createInstance } with the ID
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* of the registered object return clones of that object. Thus any
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* object passed to <tt>registerInstance()</tt> must implement
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* <tt>clone()</tt> propertly. To register a transliterator subclass
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* without instantiating it (until it is needed), users may call
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* {@link #registerFactory }. In this case, the objects are
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* instantiated by invoking the zero-argument public constructor of
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* the class.
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*
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* <p><b>Subclassing</b>
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*
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* Subclasses must implement the abstract method
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* <code>handleTransliterate()</code>. <p>Subclasses should override
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* the <code>transliterate()</code> method taking a
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* <code>Replaceable</code> and the <code>transliterate()</code>
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* method taking a <code>String</code> and <code>StringBuffer</code>
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* if the performance of these methods can be improved over the
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* performance obtained by the default implementations in this class.
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*
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* <p><b>Rule syntax</b>
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*
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* <p>A set of rules determines how to perform translations.
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* Rules within a rule set are separated by semicolons (';').
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* To include a literal semicolon, prefix it with a backslash ('\').
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* Unicode Pattern_White_Space is ignored.
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* If the first non-blank character on a line is '#',
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* the entire line is ignored as a comment.
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*
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* <p>Each set of rules consists of two groups, one forward, and one
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* reverse. This is a convention that is not enforced; rules for one
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* direction may be omitted, with the result that translations in
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* that direction will not modify the source text. In addition,
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* bidirectional forward-reverse rules may be specified for
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* symmetrical transformations.
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*
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* <p>Note: Another description of the Transliterator rule syntax is available in
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* <a href="https://www.unicode.org/reports/tr35/tr35-general.html#Transform_Rules_Syntax">section
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* Transform Rules Syntax of UTS #35: Unicode LDML</a>.
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* The rules are shown there using arrow symbols ← and → and ↔.
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* ICU supports both those and the equivalent ASCII symbols < and > and <>.
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*
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* <p>Rule statements take one of the following forms:
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*
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* <dl>
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* <dt><code>$alefmadda=\\u0622;</code></dt>
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* <dd><strong>Variable definition.</strong> The name on the
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* left is assigned the text on the right. In this example,
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* after this statement, instances of the left hand name,
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* "<code>$alefmadda</code>", will be replaced by
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* the Unicode character U+0622. Variable names must begin
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* with a letter and consist only of letters, digits, and
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* underscores. Case is significant. Duplicate names cause
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* an exception to be thrown, that is, variables cannot be
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* redefined. The right hand side may contain well-formed
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* text of any length, including no text at all ("<code>$empty=;</code>").
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* The right hand side may contain embedded <code>UnicodeSet</code>
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* patterns, for example, "<code>$softvowel=[eiyEIY]</code>".</dd>
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* <dt><code>ai>$alefmadda;</code></dt>
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* <dd><strong>Forward translation rule.</strong> This rule
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* states that the string on the left will be changed to the
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* string on the right when performing forward
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* transliteration.</dd>
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* <dt><code>ai<$alefmadda;</code></dt>
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* <dd><strong>Reverse translation rule.</strong> This rule
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* states that the string on the right will be changed to
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* the string on the left when performing reverse
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* transliteration.</dd>
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* </dl>
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*
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* <dl>
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* <dt><code>ai<>$alefmadda;</code></dt>
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* <dd><strong>Bidirectional translation rule.</strong> This
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* rule states that the string on the right will be changed
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* to the string on the left when performing forward
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* transliteration, and vice versa when performing reverse
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* transliteration.</dd>
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* </dl>
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*
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* <p>Translation rules consist of a <em>match pattern</em> and an <em>output
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* string</em>. The match pattern consists of literal characters,
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* optionally preceded by context, and optionally followed by
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* context. Context characters, like literal pattern characters,
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* must be matched in the text being transliterated. However, unlike
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* literal pattern characters, they are not replaced by the output
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* text. For example, the pattern "<code>abc{def}</code>"
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* indicates the characters "<code>def</code>" must be
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* preceded by "<code>abc</code>" for a successful match.
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* If there is a successful match, "<code>def</code>" will
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* be replaced, but not "<code>abc</code>". The final '<code>}</code>'
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* is optional, so "<code>abc{def</code>" is equivalent to
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* "<code>abc{def}</code>". Another example is "<code>{123}456</code>"
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* (or "<code>123}456</code>") in which the literal
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* pattern "<code>123</code>" must be followed by "<code>456</code>".
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*
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* <p>The output string of a forward or reverse rule consists of
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* characters to replace the literal pattern characters. If the
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* output string contains the character '<code>|</code>', this is
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* taken to indicate the location of the <em>cursor</em> after
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* replacement. The cursor is the point in the text at which the
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* next replacement, if any, will be applied. The cursor is usually
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* placed within the replacement text; however, it can actually be
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* placed into the precending or following context by using the
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* special character '@'. Examples:
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*
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* <pre>
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* a {foo} z > | @ bar; # foo -> bar, move cursor before a
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* {foo} xyz > bar @@|; # foo -> bar, cursor between y and z
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* </pre>
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*
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* <p><b>UnicodeSet</b>
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*
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* <p><code>UnicodeSet</code> patterns may appear anywhere that
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* makes sense. They may appear in variable definitions.
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* Contrariwise, <code>UnicodeSet</code> patterns may themselves
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* contain variable references, such as "<code>$a=[a-z];$not_a=[^$a]</code>",
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* or "<code>$range=a-z;$ll=[$range]</code>".
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*
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* <p><code>UnicodeSet</code> patterns may also be embedded directly
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* into rule strings. Thus, the following two rules are equivalent:
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*
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* <pre>
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* $vowel=[aeiou]; $vowel>'*'; # One way to do this
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* [aeiou]>'*'; # Another way
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* </pre>
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*
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* <p>See {@link UnicodeSet} for more documentation and examples.
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*
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* <p><b>Segments</b>
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*
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* <p>Segments of the input string can be matched and copied to the
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* output string. This makes certain sets of rules simpler and more
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* general, and makes reordering possible. For example:
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*
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* <pre>
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* ([a-z]) > $1 $1; # double lowercase letters
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* ([:Lu:]) ([:Ll:]) > $2 $1; # reverse order of Lu-Ll pairs
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* </pre>
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*
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* <p>The segment of the input string to be copied is delimited by
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* "<code>(</code>" and "<code>)</code>". Up to
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* nine segments may be defined. Segments may not overlap. In the
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* output string, "<code>$1</code>" through "<code>$9</code>"
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* represent the input string segments, in left-to-right order of
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* definition.
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*
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* <p><b>Anchors</b>
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*
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* <p>Patterns can be anchored to the beginning or the end of the text. This is done with the
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* special characters '<code>^</code>' and '<code>$</code>'. For example:
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*
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* <pre>
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* ^ a > 'BEG_A'; # match 'a' at start of text
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* a > 'A'; # match other instances of 'a'
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* z $ > 'END_Z'; # match 'z' at end of text
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* z > 'Z'; # match other instances of 'z'
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* </pre>
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*
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* <p>It is also possible to match the beginning or the end of the text using a <code>UnicodeSet</code>.
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* This is done by including a virtual anchor character '<code>$</code>' at the end of the
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* set pattern. Although this is usually the match chafacter for the end anchor, the set will
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* match either the beginning or the end of the text, depending on its placement. For
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* example:
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*
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* <pre>
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* $x = [a-z$]; # match 'a' through 'z' OR anchor
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* $x 1 > 2; # match '1' after a-z or at the start
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* 3 $x > 4; # match '3' before a-z or at the end
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* </pre>
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*
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* <p><b>Example</b>
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*
|
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* <p>The following example rules illustrate many of the features of
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* the rule language.
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*
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* <table border="0" cellpadding="4">
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* <tr>
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* <td style="vertical-align: top;">Rule 1.</td>
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* <td style="vertical-align: top; write-space: nowrap;"><code>abc{def}>x|y</code></td>
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* </tr>
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* <tr>
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* <td style="vertical-align: top;">Rule 2.</td>
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* <td style="vertical-align: top; write-space: nowrap;"><code>xyz>r</code></td>
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* </tr>
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* <tr>
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* <td style="vertical-align: top;">Rule 3.</td>
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* <td style="vertical-align: top; write-space: nowrap;"><code>yz>q</code></td>
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* </tr>
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* </table>
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*
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* <p>Applying these rules to the string "<code>adefabcdefz</code>"
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* yields the following results:
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*
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* <table border="0" cellpadding="4">
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* <tr>
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* <td style="vertical-align: top; write-space: nowrap;"><code>|adefabcdefz</code></td>
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* <td style="vertical-align: top;">Initial state, no rules match. Advance
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* cursor.</td>
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* </tr>
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* <tr>
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* <td style="vertical-align: top; write-space: nowrap;"><code>a|defabcdefz</code></td>
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|
* <td style="vertical-align: top;">Still no match. Rule 1 does not match
|
|
* because the preceding context is not present.</td>
|
|
* </tr>
|
|
* <tr>
|
|
* <td style="vertical-align: top; write-space: nowrap;"><code>ad|efabcdefz</code></td>
|
|
* <td style="vertical-align: top;">Still no match. Keep advancing until
|
|
* there is a match...</td>
|
|
* </tr>
|
|
* <tr>
|
|
* <td style="vertical-align: top; write-space: nowrap;"><code>ade|fabcdefz</code></td>
|
|
* <td style="vertical-align: top;">...</td>
|
|
* </tr>
|
|
* <tr>
|
|
* <td style="vertical-align: top; write-space: nowrap;"><code>adef|abcdefz</code></td>
|
|
* <td style="vertical-align: top;">...</td>
|
|
* </tr>
|
|
* <tr>
|
|
* <td style="vertical-align: top; write-space: nowrap;"><code>adefa|bcdefz</code></td>
|
|
* <td style="vertical-align: top;">...</td>
|
|
* </tr>
|
|
* <tr>
|
|
* <td style="vertical-align: top; write-space: nowrap;"><code>adefab|cdefz</code></td>
|
|
* <td style="vertical-align: top;">...</td>
|
|
* </tr>
|
|
* <tr>
|
|
* <td style="vertical-align: top; write-space: nowrap;"><code>adefabc|defz</code></td>
|
|
* <td style="vertical-align: top;">Rule 1 matches; replace "<code>def</code>"
|
|
* with "<code>xy</code>" and back up the cursor
|
|
* to before the '<code>y</code>'.</td>
|
|
* </tr>
|
|
* <tr>
|
|
* <td style="vertical-align: top; write-space: nowrap;"><code>adefabcx|yz</code></td>
|
|
* <td style="vertical-align: top;">Although "<code>xyz</code>" is
|
|
* present, rule 2 does not match because the cursor is
|
|
* before the '<code>y</code>', not before the '<code>x</code>'.
|
|
* Rule 3 does match. Replace "<code>yz</code>"
|
|
* with "<code>q</code>".</td>
|
|
* </tr>
|
|
* <tr>
|
|
* <td style="vertical-align: top; write-space: nowrap;"><code>adefabcxq|</code></td>
|
|
* <td style="vertical-align: top;">The cursor is at the end;
|
|
* transliteration is complete.</td>
|
|
* </tr>
|
|
* </table>
|
|
*
|
|
* <p>The order of rules is significant. If multiple rules may match
|
|
* at some point, the first matching rule is applied.
|
|
*
|
|
* <p>Forward and reverse rules may have an empty output string.
|
|
* Otherwise, an empty left or right hand side of any statement is a
|
|
* syntax error.
|
|
*
|
|
* <p>Single quotes are used to quote any character other than a
|
|
* digit or letter. To specify a single quote itself, inside or
|
|
* outside of quotes, use two single quotes in a row. For example,
|
|
* the rule "<code>'>'>o''clock</code>" changes the
|
|
* string "<code>></code>" to the string "<code>o'clock</code>".
|
|
*
|
|
* <p><b>Notes</b>
|
|
*
|
|
* <p>While a Transliterator is being built from rules, it checks that
|
|
* the rules are added in proper order. For example, if the rule
|
|
* "a>x" is followed by the rule "ab>y",
|
|
* then the second rule will throw an exception. The reason is that
|
|
* the second rule can never be triggered, since the first rule
|
|
* always matches anything it matches. In other words, the first
|
|
* rule <em>masks</em> the second rule.
|
|
*
|
|
* @author Alan Liu
|
|
* @stable ICU 2.0
|
|
*/
|
|
class U_I18N_API Transliterator : public UObject {
|
|
|
|
private:
|
|
|
|
/**
|
|
* Programmatic name, e.g., "Latin-Arabic".
|
|
*/
|
|
UnicodeString ID;
|
|
|
|
/**
|
|
* This transliterator's filter. Any character for which
|
|
* <tt>filter.contains()</tt> returns <tt>false</tt> will not be
|
|
* altered by this transliterator. If <tt>filter</tt> is
|
|
* <tt>null</tt> then no filtering is applied.
|
|
*/
|
|
UnicodeFilter* filter;
|
|
|
|
int32_t maximumContextLength;
|
|
|
|
public:
|
|
|
|
/**
|
|
* A context integer or pointer for a factory function, passed by
|
|
* value.
|
|
* @stable ICU 2.4
|
|
*/
|
|
union Token {
|
|
/**
|
|
* This token, interpreted as a 32-bit integer.
|
|
* @stable ICU 2.4
|
|
*/
|
|
int32_t integer;
|
|
/**
|
|
* This token, interpreted as a native pointer.
|
|
* @stable ICU 2.4
|
|
*/
|
|
void* pointer;
|
|
};
|
|
|
|
#ifndef U_HIDE_INTERNAL_API
|
|
/**
|
|
* Return a token containing an integer.
|
|
* @return a token containing an integer.
|
|
* @internal
|
|
*/
|
|
inline static Token integerToken(int32_t);
|
|
|
|
/**
|
|
* Return a token containing a pointer.
|
|
* @return a token containing a pointer.
|
|
* @internal
|
|
*/
|
|
inline static Token pointerToken(void*);
|
|
#endif /* U_HIDE_INTERNAL_API */
|
|
|
|
/**
|
|
* A function that creates and returns a Transliterator. When
|
|
* invoked, it will be passed the ID string that is being
|
|
* instantiated, together with the context pointer that was passed
|
|
* in when the factory function was first registered. Many
|
|
* factory functions will ignore both parameters, however,
|
|
* functions that are registered to more than one ID may use the
|
|
* ID or the context parameter to parameterize the transliterator
|
|
* they create.
|
|
* @param ID the string identifier for this transliterator
|
|
* @param context a context pointer that will be stored and
|
|
* later passed to the factory function when an ID matching
|
|
* the registration ID is being instantiated with this factory.
|
|
* @stable ICU 2.4
|
|
*/
|
|
typedef Transliterator* (U_EXPORT2 *Factory)(const UnicodeString& ID, Token context);
|
|
|
|
protected:
|
|
|
|
/**
|
|
* Default constructor.
|
|
* @param ID the string identifier for this transliterator
|
|
* @param adoptedFilter the filter. Any character for which
|
|
* <tt>filter.contains()</tt> returns <tt>false</tt> will not be
|
|
* altered by this transliterator. If <tt>filter</tt> is
|
|
* <tt>null</tt> then no filtering is applied.
|
|
* @stable ICU 2.4
|
|
*/
|
|
Transliterator(const UnicodeString& ID, UnicodeFilter* adoptedFilter);
|
|
|
|
/**
|
|
* Copy constructor.
|
|
* @stable ICU 2.4
|
|
*/
|
|
Transliterator(const Transliterator&);
|
|
|
|
/**
|
|
* Assignment operator.
|
|
* @stable ICU 2.4
|
|
*/
|
|
Transliterator& operator=(const Transliterator&);
|
|
|
|
/**
|
|
* Create a transliterator from a basic ID. This is an ID
|
|
* containing only the forward direction source, target, and
|
|
* variant.
|
|
* @param id a basic ID of the form S-T or S-T/V.
|
|
* @param canon canonical ID to assign to the object, or
|
|
* NULL to leave the ID unchanged
|
|
* @return a newly created Transliterator or null if the ID is
|
|
* invalid.
|
|
* @stable ICU 2.4
|
|
*/
|
|
static Transliterator* createBasicInstance(const UnicodeString& id,
|
|
const UnicodeString* canon);
|
|
|
|
friend class TransliteratorParser; // for parseID()
|
|
friend class TransliteratorIDParser; // for createBasicInstance()
|
|
friend class TransliteratorAlias; // for setID()
|
|
|
|
public:
|
|
|
|
/**
|
|
* Destructor.
|
|
* @stable ICU 2.0
|
|
*/
|
|
virtual ~Transliterator();
|
|
|
|
/**
|
|
* Implements Cloneable.
|
|
* All subclasses are encouraged to implement this method if it is
|
|
* possible and reasonable to do so. Subclasses that are to be
|
|
* registered with the system using <tt>registerInstance()</tt>
|
|
* are required to implement this method. If a subclass does not
|
|
* implement clone() properly and is registered with the system
|
|
* using registerInstance(), then the default clone() implementation
|
|
* will return null, and calls to createInstance() will fail.
|
|
*
|
|
* @return a copy of the object.
|
|
* @see #registerInstance
|
|
* @stable ICU 2.0
|
|
*/
|
|
virtual Transliterator* clone() const;
|
|
|
|
/**
|
|
* Transliterates a segment of a string, with optional filtering.
|
|
*
|
|
* @param text the string to be transliterated
|
|
* @param start the beginning index, inclusive; <code>0 <= start
|
|
* <= limit</code>.
|
|
* @param limit the ending index, exclusive; <code>start <= limit
|
|
* <= text.length()</code>.
|
|
* @return The new limit index. The text previously occupying <code>[start,
|
|
* limit)</code> has been transliterated, possibly to a string of a different
|
|
* length, at <code>[start, </code><em>new-limit</em><code>)</code>, where
|
|
* <em>new-limit</em> is the return value. If the input offsets are out of bounds,
|
|
* the returned value is -1 and the input string remains unchanged.
|
|
* @stable ICU 2.0
|
|
*/
|
|
virtual int32_t transliterate(Replaceable& text,
|
|
int32_t start, int32_t limit) const;
|
|
|
|
/**
|
|
* Transliterates an entire string in place. Convenience method.
|
|
* @param text the string to be transliterated
|
|
* @stable ICU 2.0
|
|
*/
|
|
virtual void transliterate(Replaceable& text) const;
|
|
|
|
/**
|
|
* Transliterates the portion of the text buffer that can be
|
|
* transliterated unambiguosly after new text has been inserted,
|
|
* typically as a result of a keyboard event. The new text in
|
|
* <code>insertion</code> will be inserted into <code>text</code>
|
|
* at <code>index.limit</code>, advancing
|
|
* <code>index.limit</code> by <code>insertion.length()</code>.
|
|
* Then the transliterator will try to transliterate characters of
|
|
* <code>text</code> between <code>index.cursor</code> and
|
|
* <code>index.limit</code>. Characters before
|
|
* <code>index.cursor</code> will not be changed.
|
|
*
|
|
* <p>Upon return, values in <code>index</code> will be updated.
|
|
* <code>index.start</code> will be advanced to the first
|
|
* character that future calls to this method will read.
|
|
* <code>index.cursor</code> and <code>index.limit</code> will
|
|
* be adjusted to delimit the range of text that future calls to
|
|
* this method may change.
|
|
*
|
|
* <p>Typical usage of this method begins with an initial call
|
|
* with <code>index.start</code> and <code>index.limit</code>
|
|
* set to indicate the portion of <code>text</code> to be
|
|
* transliterated, and <code>index.cursor == index.start</code>.
|
|
* Thereafter, <code>index</code> can be used without
|
|
* modification in future calls, provided that all changes to
|
|
* <code>text</code> are made via this method.
|
|
*
|
|
* <p>This method assumes that future calls may be made that will
|
|
* insert new text into the buffer. As a result, it only performs
|
|
* unambiguous transliterations. After the last call to this
|
|
* method, there may be untransliterated text that is waiting for
|
|
* more input to resolve an ambiguity. In order to perform these
|
|
* pending transliterations, clients should call {@link
|
|
* #finishTransliteration } after the last call to this
|
|
* method has been made.
|
|
*
|
|
* @param text the buffer holding transliterated and untransliterated text
|
|
* @param index an array of three integers.
|
|
*
|
|
* <ul><li><code>index.start</code>: the beginning index,
|
|
* inclusive; <code>0 <= index.start <= index.limit</code>.
|
|
*
|
|
* <li><code>index.limit</code>: the ending index, exclusive;
|
|
* <code>index.start <= index.limit <= text.length()</code>.
|
|
* <code>insertion</code> is inserted at
|
|
* <code>index.limit</code>.
|
|
*
|
|
* <li><code>index.cursor</code>: the next character to be
|
|
* considered for transliteration; <code>index.start <=
|
|
* index.cursor <= index.limit</code>. Characters before
|
|
* <code>index.cursor</code> will not be changed by future calls
|
|
* to this method.</ul>
|
|
*
|
|
* @param insertion text to be inserted and possibly
|
|
* transliterated into the translation buffer at
|
|
* <code>index.limit</code>. If <code>null</code> then no text
|
|
* is inserted.
|
|
* @param status Output param to filled in with a success or an error.
|
|
* @see #handleTransliterate
|
|
* @exception IllegalArgumentException if <code>index</code>
|
|
* is invalid
|
|
* @see UTransPosition
|
|
* @stable ICU 2.0
|
|
*/
|
|
virtual void transliterate(Replaceable& text, UTransPosition& index,
|
|
const UnicodeString& insertion,
|
|
UErrorCode& status) const;
|
|
|
|
/**
|
|
* Transliterates the portion of the text buffer that can be
|
|
* transliterated unambiguosly after a new character has been
|
|
* inserted, typically as a result of a keyboard event. This is a
|
|
* convenience method.
|
|
* @param text the buffer holding transliterated and
|
|
* untransliterated text
|
|
* @param index an array of three integers.
|
|
* @param insertion text to be inserted and possibly
|
|
* transliterated into the translation buffer at
|
|
* <code>index.limit</code>.
|
|
* @param status Output param to filled in with a success or an error.
|
|
* @see #transliterate(Replaceable&, UTransPosition&, const UnicodeString&, UErrorCode&) const
|
|
* @stable ICU 2.0
|
|
*/
|
|
virtual void transliterate(Replaceable& text, UTransPosition& index,
|
|
UChar32 insertion,
|
|
UErrorCode& status) const;
|
|
|
|
/**
|
|
* Transliterates the portion of the text buffer that can be
|
|
* transliterated unambiguosly. This is a convenience method; see
|
|
* {@link
|
|
* #transliterate(Replaceable&, UTransPosition&, const UnicodeString&, UErrorCode&) const }
|
|
* for details.
|
|
* @param text the buffer holding transliterated and
|
|
* untransliterated text
|
|
* @param index an array of three integers.
|
|
* @param status Output param to filled in with a success or an error.
|
|
* @see #transliterate(Replaceable&, UTransPosition&, const UnicodeString&, UErrorCode &) const
|
|
* @stable ICU 2.0
|
|
*/
|
|
virtual void transliterate(Replaceable& text, UTransPosition& index,
|
|
UErrorCode& status) const;
|
|
|
|
/**
|
|
* Finishes any pending transliterations that were waiting for
|
|
* more characters. Clients should call this method as the last
|
|
* call after a sequence of one or more calls to
|
|
* <code>transliterate()</code>.
|
|
* @param text the buffer holding transliterated and
|
|
* untransliterated text.
|
|
* @param index the array of indices previously passed to {@link
|
|
* #transliterate }
|
|
* @stable ICU 2.0
|
|
*/
|
|
virtual void finishTransliteration(Replaceable& text,
|
|
UTransPosition& index) const;
|
|
|
|
private:
|
|
|
|
/**
|
|
* This internal method does incremental transliteration. If the
|
|
* 'insertion' is non-null then we append it to 'text' before
|
|
* proceeding. This method calls through to the pure virtual
|
|
* framework method handleTransliterate() to do the actual
|
|
* work.
|
|
* @param text the buffer holding transliterated and
|
|
* untransliterated text
|
|
* @param index an array of three integers. See {@link
|
|
* #transliterate(Replaceable, int[], String)}.
|
|
* @param insertion text to be inserted and possibly
|
|
* transliterated into the translation buffer at
|
|
* <code>index.limit</code>.
|
|
* @param status Output param to filled in with a success or an error.
|
|
*/
|
|
void _transliterate(Replaceable& text,
|
|
UTransPosition& index,
|
|
const UnicodeString* insertion,
|
|
UErrorCode &status) const;
|
|
|
|
protected:
|
|
|
|
/**
|
|
* Abstract method that concrete subclasses define to implement
|
|
* their transliteration algorithm. This method handles both
|
|
* incremental and non-incremental transliteration. Let
|
|
* <code>originalStart</code> refer to the value of
|
|
* <code>pos.start</code> upon entry.
|
|
*
|
|
* <ul>
|
|
* <li>If <code>incremental</code> is false, then this method
|
|
* should transliterate all characters between
|
|
* <code>pos.start</code> and <code>pos.limit</code>. Upon return
|
|
* <code>pos.start</code> must == <code> pos.limit</code>.</li>
|
|
*
|
|
* <li>If <code>incremental</code> is true, then this method
|
|
* should transliterate all characters between
|
|
* <code>pos.start</code> and <code>pos.limit</code> that can be
|
|
* unambiguously transliterated, regardless of future insertions
|
|
* of text at <code>pos.limit</code>. Upon return,
|
|
* <code>pos.start</code> should be in the range
|
|
* [<code>originalStart</code>, <code>pos.limit</code>).
|
|
* <code>pos.start</code> should be positioned such that
|
|
* characters [<code>originalStart</code>, <code>
|
|
* pos.start</code>) will not be changed in the future by this
|
|
* transliterator and characters [<code>pos.start</code>,
|
|
* <code>pos.limit</code>) are unchanged.</li>
|
|
* </ul>
|
|
*
|
|
* <p>Implementations of this method should also obey the
|
|
* following invariants:</p>
|
|
*
|
|
* <ul>
|
|
* <li> <code>pos.limit</code> and <code>pos.contextLimit</code>
|
|
* should be updated to reflect changes in length of the text
|
|
* between <code>pos.start</code> and <code>pos.limit</code>. The
|
|
* difference <code> pos.contextLimit - pos.limit</code> should
|
|
* not change.</li>
|
|
*
|
|
* <li><code>pos.contextStart</code> should not change.</li>
|
|
*
|
|
* <li>Upon return, neither <code>pos.start</code> nor
|
|
* <code>pos.limit</code> should be less than
|
|
* <code>originalStart</code>.</li>
|
|
*
|
|
* <li>Text before <code>originalStart</code> and text after
|
|
* <code>pos.limit</code> should not change.</li>
|
|
*
|
|
* <li>Text before <code>pos.contextStart</code> and text after
|
|
* <code> pos.contextLimit</code> should be ignored.</li>
|
|
* </ul>
|
|
*
|
|
* <p>Subclasses may safely assume that all characters in
|
|
* [<code>pos.start</code>, <code>pos.limit</code>) are filtered.
|
|
* In other words, the filter has already been applied by the time
|
|
* this method is called. See
|
|
* <code>filteredTransliterate()</code>.
|
|
*
|
|
* <p>This method is <b>not</b> for public consumption. Calling
|
|
* this method directly will transliterate
|
|
* [<code>pos.start</code>, <code>pos.limit</code>) without
|
|
* applying the filter. End user code should call <code>
|
|
* transliterate()</code> instead of this method. Subclass code
|
|
* and wrapping transliterators should call
|
|
* <code>filteredTransliterate()</code> instead of this method.<p>
|
|
*
|
|
* @param text the buffer holding transliterated and
|
|
* untransliterated text
|
|
*
|
|
* @param pos the indices indicating the start, limit, context
|
|
* start, and context limit of the text.
|
|
*
|
|
* @param incremental if true, assume more text may be inserted at
|
|
* <code>pos.limit</code> and act accordingly. Otherwise,
|
|
* transliterate all text between <code>pos.start</code> and
|
|
* <code>pos.limit</code> and move <code>pos.start</code> up to
|
|
* <code>pos.limit</code>.
|
|
*
|
|
* @see #transliterate
|
|
* @stable ICU 2.4
|
|
*/
|
|
virtual void handleTransliterate(Replaceable& text,
|
|
UTransPosition& pos,
|
|
UBool incremental) const = 0;
|
|
|
|
public:
|
|
/**
|
|
* Transliterate a substring of text, as specified by index, taking filters
|
|
* into account. This method is for subclasses that need to delegate to
|
|
* another transliterator.
|
|
* @param text the text to be transliterated
|
|
* @param index the position indices
|
|
* @param incremental if true, then assume more characters may be inserted
|
|
* at index.limit, and postpone processing to accomodate future incoming
|
|
* characters
|
|
* @stable ICU 2.4
|
|
*/
|
|
virtual void filteredTransliterate(Replaceable& text,
|
|
UTransPosition& index,
|
|
UBool incremental) const;
|
|
|
|
private:
|
|
|
|
/**
|
|
* Top-level transliteration method, handling filtering, incremental and
|
|
* non-incremental transliteration, and rollback. All transliteration
|
|
* public API methods eventually call this method with a rollback argument
|
|
* of true. Other entities may call this method but rollback should be
|
|
* false.
|
|
*
|
|
* <p>If this transliterator has a filter, break up the input text into runs
|
|
* of unfiltered characters. Pass each run to
|
|
* subclass.handleTransliterate().
|
|
*
|
|
* <p>In incremental mode, if rollback is true, perform a special
|
|
* incremental procedure in which several passes are made over the input
|
|
* text, adding one character at a time, and committing successful
|
|
* transliterations as they occur. Unsuccessful transliterations are rolled
|
|
* back and retried with additional characters to give correct results.
|
|
*
|
|
* @param text the text to be transliterated
|
|
* @param index the position indices
|
|
* @param incremental if true, then assume more characters may be inserted
|
|
* at index.limit, and postpone processing to accomodate future incoming
|
|
* characters
|
|
* @param rollback if true and if incremental is true, then perform special
|
|
* incremental processing, as described above, and undo partial
|
|
* transliterations where necessary. If incremental is false then this
|
|
* parameter is ignored.
|
|
*/
|
|
virtual void filteredTransliterate(Replaceable& text,
|
|
UTransPosition& index,
|
|
UBool incremental,
|
|
UBool rollback) const;
|
|
|
|
public:
|
|
|
|
/**
|
|
* Returns the length of the longest context required by this transliterator.
|
|
* This is <em>preceding</em> context. The default implementation supplied
|
|
* by <code>Transliterator</code> returns zero; subclasses
|
|
* that use preceding context should override this method to return the
|
|
* correct value. For example, if a transliterator translates "ddd" (where
|
|
* d is any digit) to "555" when preceded by "(ddd)", then the preceding
|
|
* context length is 5, the length of "(ddd)".
|
|
*
|
|
* @return The maximum number of preceding context characters this
|
|
* transliterator needs to examine
|
|
* @stable ICU 2.0
|
|
*/
|
|
int32_t getMaximumContextLength(void) const;
|
|
|
|
protected:
|
|
|
|
/**
|
|
* Method for subclasses to use to set the maximum context length.
|
|
* @param maxContextLength the new value to be set.
|
|
* @see #getMaximumContextLength
|
|
* @stable ICU 2.4
|
|
*/
|
|
void setMaximumContextLength(int32_t maxContextLength);
|
|
|
|
public:
|
|
|
|
/**
|
|
* Returns a programmatic identifier for this transliterator.
|
|
* If this identifier is passed to <code>createInstance()</code>, it
|
|
* will return this object, if it has been registered.
|
|
* @return a programmatic identifier for this transliterator.
|
|
* @see #registerInstance
|
|
* @see #registerFactory
|
|
* @see #getAvailableIDs
|
|
* @stable ICU 2.0
|
|
*/
|
|
virtual const UnicodeString& getID(void) const;
|
|
|
|
/**
|
|
* Returns a name for this transliterator that is appropriate for
|
|
* display to the user in the default locale. See {@link
|
|
* #getDisplayName } for details.
|
|
* @param ID the string identifier for this transliterator
|
|
* @param result Output param to receive the display name
|
|
* @return A reference to 'result'.
|
|
* @stable ICU 2.0
|
|
*/
|
|
static UnicodeString& U_EXPORT2 getDisplayName(const UnicodeString& ID,
|
|
UnicodeString& result);
|
|
|
|
/**
|
|
* Returns a name for this transliterator that is appropriate for
|
|
* display to the user in the given locale. This name is taken
|
|
* from the locale resource data in the standard manner of the
|
|
* <code>java.text</code> package.
|
|
*
|
|
* <p>If no localized names exist in the system resource bundles,
|
|
* a name is synthesized using a localized
|
|
* <code>MessageFormat</code> pattern from the resource data. The
|
|
* arguments to this pattern are an integer followed by one or two
|
|
* strings. The integer is the number of strings, either 1 or 2.
|
|
* The strings are formed by splitting the ID for this
|
|
* transliterator at the first '-'. If there is no '-', then the
|
|
* entire ID forms the only string.
|
|
* @param ID the string identifier for this transliterator
|
|
* @param inLocale the Locale in which the display name should be
|
|
* localized.
|
|
* @param result Output param to receive the display name
|
|
* @return A reference to 'result'.
|
|
* @stable ICU 2.0
|
|
*/
|
|
static UnicodeString& U_EXPORT2 getDisplayName(const UnicodeString& ID,
|
|
const Locale& inLocale,
|
|
UnicodeString& result);
|
|
|
|
/**
|
|
* Returns the filter used by this transliterator, or <tt>NULL</tt>
|
|
* if this transliterator uses no filter.
|
|
* @return the filter used by this transliterator, or <tt>NULL</tt>
|
|
* if this transliterator uses no filter.
|
|
* @stable ICU 2.0
|
|
*/
|
|
const UnicodeFilter* getFilter(void) const;
|
|
|
|
/**
|
|
* Returns the filter used by this transliterator, or <tt>NULL</tt> if this
|
|
* transliterator uses no filter. The caller must eventually delete the
|
|
* result. After this call, this transliterator's filter is set to
|
|
* <tt>NULL</tt>.
|
|
* @return the filter used by this transliterator, or <tt>NULL</tt> if this
|
|
* transliterator uses no filter.
|
|
* @stable ICU 2.4
|
|
*/
|
|
UnicodeFilter* orphanFilter(void);
|
|
|
|
/**
|
|
* Changes the filter used by this transliterator. If the filter
|
|
* is set to <tt>null</tt> then no filtering will occur.
|
|
*
|
|
* <p>Callers must take care if a transliterator is in use by
|
|
* multiple threads. The filter should not be changed by one
|
|
* thread while another thread may be transliterating.
|
|
* @param adoptedFilter the new filter to be adopted.
|
|
* @stable ICU 2.0
|
|
*/
|
|
void adoptFilter(UnicodeFilter* adoptedFilter);
|
|
|
|
/**
|
|
* Returns this transliterator's inverse. See the class
|
|
* documentation for details. This implementation simply inverts
|
|
* the two entities in the ID and attempts to retrieve the
|
|
* resulting transliterator. That is, if <code>getID()</code>
|
|
* returns "A-B", then this method will return the result of
|
|
* <code>createInstance("B-A")</code>, or <code>null</code> if that
|
|
* call fails.
|
|
*
|
|
* <p>Subclasses with knowledge of their inverse may wish to
|
|
* override this method.
|
|
*
|
|
* @param status Output param to filled in with a success or an error.
|
|
* @return a transliterator that is an inverse, not necessarily
|
|
* exact, of this transliterator, or <code>null</code> if no such
|
|
* transliterator is registered.
|
|
* @see #registerInstance
|
|
* @stable ICU 2.0
|
|
*/
|
|
Transliterator* createInverse(UErrorCode& status) const;
|
|
|
|
/**
|
|
* Returns a <code>Transliterator</code> object given its ID.
|
|
* The ID must be either a system transliterator ID or a ID registered
|
|
* using <code>registerInstance()</code>.
|
|
*
|
|
* @param ID a valid ID, as enumerated by <code>getAvailableIDs()</code>
|
|
* @param dir either FORWARD or REVERSE.
|
|
* @param parseError Struct to recieve information on position
|
|
* of error if an error is encountered
|
|
* @param status Output param to filled in with a success or an error.
|
|
* @return A <code>Transliterator</code> object with the given ID
|
|
* @see #registerInstance
|
|
* @see #getAvailableIDs
|
|
* @see #getID
|
|
* @stable ICU 2.0
|
|
*/
|
|
static Transliterator* U_EXPORT2 createInstance(const UnicodeString& ID,
|
|
UTransDirection dir,
|
|
UParseError& parseError,
|
|
UErrorCode& status);
|
|
|
|
/**
|
|
* Returns a <code>Transliterator</code> object given its ID.
|
|
* The ID must be either a system transliterator ID or a ID registered
|
|
* using <code>registerInstance()</code>.
|
|
* @param ID a valid ID, as enumerated by <code>getAvailableIDs()</code>
|
|
* @param dir either FORWARD or REVERSE.
|
|
* @param status Output param to filled in with a success or an error.
|
|
* @return A <code>Transliterator</code> object with the given ID
|
|
* @stable ICU 2.0
|
|
*/
|
|
static Transliterator* U_EXPORT2 createInstance(const UnicodeString& ID,
|
|
UTransDirection dir,
|
|
UErrorCode& status);
|
|
|
|
/**
|
|
* Returns a <code>Transliterator</code> object constructed from
|
|
* the given rule string. This will be a rule-based Transliterator,
|
|
* if the rule string contains only rules, or a
|
|
* compound Transliterator, if it contains ID blocks, or a
|
|
* null Transliterator, if it contains ID blocks which parse as
|
|
* empty for the given direction.
|
|
*
|
|
* @param ID the id for the transliterator.
|
|
* @param rules rules, separated by ';'
|
|
* @param dir either FORWARD or REVERSE.
|
|
* @param parseError Struct to receive information on position
|
|
* of error if an error is encountered
|
|
* @param status Output param set to success/failure code.
|
|
* @return a newly created Transliterator
|
|
* @stable ICU 2.0
|
|
*/
|
|
static Transliterator* U_EXPORT2 createFromRules(const UnicodeString& ID,
|
|
const UnicodeString& rules,
|
|
UTransDirection dir,
|
|
UParseError& parseError,
|
|
UErrorCode& status);
|
|
|
|
/**
|
|
* Create a rule string that can be passed to createFromRules()
|
|
* to recreate this transliterator.
|
|
* @param result the string to receive the rules. Previous
|
|
* contents will be deleted.
|
|
* @param escapeUnprintable if true then convert unprintable
|
|
* character to their hex escape representations, \\uxxxx or
|
|
* \\Uxxxxxxxx. Unprintable characters are those other than
|
|
* U+000A, U+0020..U+007E.
|
|
* @stable ICU 2.0
|
|
*/
|
|
virtual UnicodeString& toRules(UnicodeString& result,
|
|
UBool escapeUnprintable) const;
|
|
|
|
/**
|
|
* Return the number of elements that make up this transliterator.
|
|
* For example, if the transliterator "NFD;Jamo-Latin;Latin-Greek"
|
|
* were created, the return value of this method would be 3.
|
|
*
|
|
* <p>If this transliterator is not composed of other
|
|
* transliterators, then this method returns 1.
|
|
* @return the number of transliterators that compose this
|
|
* transliterator, or 1 if this transliterator is not composed of
|
|
* multiple transliterators
|
|
* @stable ICU 3.0
|
|
*/
|
|
int32_t countElements() const;
|
|
|
|
/**
|
|
* Return an element that makes up this transliterator. For
|
|
* example, if the transliterator "NFD;Jamo-Latin;Latin-Greek"
|
|
* were created, the return value of this method would be one
|
|
* of the three transliterator objects that make up that
|
|
* transliterator: [NFD, Jamo-Latin, Latin-Greek].
|
|
*
|
|
* <p>If this transliterator is not composed of other
|
|
* transliterators, then this method will return a reference to
|
|
* this transliterator when given the index 0.
|
|
* @param index a value from 0..countElements()-1 indicating the
|
|
* transliterator to return
|
|
* @param ec input-output error code
|
|
* @return one of the transliterators that makes up this
|
|
* transliterator, if this transliterator is made up of multiple
|
|
* transliterators, otherwise a reference to this object if given
|
|
* an index of 0
|
|
* @stable ICU 3.0
|
|
*/
|
|
const Transliterator& getElement(int32_t index, UErrorCode& ec) const;
|
|
|
|
/**
|
|
* Returns the set of all characters that may be modified in the
|
|
* input text by this Transliterator. This incorporates this
|
|
* object's current filter; if the filter is changed, the return
|
|
* value of this function will change. The default implementation
|
|
* returns an empty set. Some subclasses may override {@link
|
|
* #handleGetSourceSet } to return a more precise result. The
|
|
* return result is approximate in any case and is intended for
|
|
* use by tests, tools, or utilities.
|
|
* @param result receives result set; previous contents lost
|
|
* @return a reference to result
|
|
* @see #getTargetSet
|
|
* @see #handleGetSourceSet
|
|
* @stable ICU 2.4
|
|
*/
|
|
UnicodeSet& getSourceSet(UnicodeSet& result) const;
|
|
|
|
/**
|
|
* Framework method that returns the set of all characters that
|
|
* may be modified in the input text by this Transliterator,
|
|
* ignoring the effect of this object's filter. The base class
|
|
* implementation returns the empty set. Subclasses that wish to
|
|
* implement this should override this method.
|
|
* @return the set of characters that this transliterator may
|
|
* modify. The set may be modified, so subclasses should return a
|
|
* newly-created object.
|
|
* @param result receives result set; previous contents lost
|
|
* @see #getSourceSet
|
|
* @see #getTargetSet
|
|
* @stable ICU 2.4
|
|
*/
|
|
virtual void handleGetSourceSet(UnicodeSet& result) const;
|
|
|
|
/**
|
|
* Returns the set of all characters that may be generated as
|
|
* replacement text by this transliterator. The default
|
|
* implementation returns the empty set. Some subclasses may
|
|
* override this method to return a more precise result. The
|
|
* return result is approximate in any case and is intended for
|
|
* use by tests, tools, or utilities requiring such
|
|
* meta-information.
|
|
* @param result receives result set; previous contents lost
|
|
* @return a reference to result
|
|
* @see #getTargetSet
|
|
* @stable ICU 2.4
|
|
*/
|
|
virtual UnicodeSet& getTargetSet(UnicodeSet& result) const;
|
|
|
|
public:
|
|
|
|
/**
|
|
* Registers a factory function that creates transliterators of
|
|
* a given ID.
|
|
*
|
|
* Because ICU may choose to cache Transliterators internally, this must
|
|
* be called at application startup, prior to any calls to
|
|
* Transliterator::createXXX to avoid undefined behavior.
|
|
*
|
|
* @param id the ID being registered
|
|
* @param factory a function pointer that will be copied and
|
|
* called later when the given ID is passed to createInstance()
|
|
* @param context a context pointer that will be stored and
|
|
* later passed to the factory function when an ID matching
|
|
* the registration ID is being instantiated with this factory.
|
|
* @stable ICU 2.0
|
|
*/
|
|
static void U_EXPORT2 registerFactory(const UnicodeString& id,
|
|
Factory factory,
|
|
Token context);
|
|
|
|
/**
|
|
* Registers an instance <tt>obj</tt> of a subclass of
|
|
* <code>Transliterator</code> with the system. When
|
|
* <tt>createInstance()</tt> is called with an ID string that is
|
|
* equal to <tt>obj->getID()</tt>, then <tt>obj->clone()</tt> is
|
|
* returned.
|
|
*
|
|
* After this call the Transliterator class owns the adoptedObj
|
|
* and will delete it.
|
|
*
|
|
* Because ICU may choose to cache Transliterators internally, this must
|
|
* be called at application startup, prior to any calls to
|
|
* Transliterator::createXXX to avoid undefined behavior.
|
|
*
|
|
* @param adoptedObj an instance of subclass of
|
|
* <code>Transliterator</code> that defines <tt>clone()</tt>
|
|
* @see #createInstance
|
|
* @see #registerFactory
|
|
* @see #unregister
|
|
* @stable ICU 2.0
|
|
*/
|
|
static void U_EXPORT2 registerInstance(Transliterator* adoptedObj);
|
|
|
|
/**
|
|
* Registers an ID string as an alias of another ID string.
|
|
* That is, after calling this function, <tt>createInstance(aliasID)</tt>
|
|
* will return the same thing as <tt>createInstance(realID)</tt>.
|
|
* This is generally used to create shorter, more mnemonic aliases
|
|
* for long compound IDs.
|
|
*
|
|
* @param aliasID The new ID being registered.
|
|
* @param realID The ID that the new ID is to be an alias for.
|
|
* This can be a compound ID and can include filters and should
|
|
* refer to transliterators that have already been registered with
|
|
* the framework, although this isn't checked.
|
|
* @stable ICU 3.6
|
|
*/
|
|
static void U_EXPORT2 registerAlias(const UnicodeString& aliasID,
|
|
const UnicodeString& realID);
|
|
|
|
protected:
|
|
|
|
#ifndef U_HIDE_INTERNAL_API
|
|
/**
|
|
* @param id the ID being registered
|
|
* @param factory a function pointer that will be copied and
|
|
* called later when the given ID is passed to createInstance()
|
|
* @param context a context pointer that will be stored and
|
|
* later passed to the factory function when an ID matching
|
|
* the registration ID is being instantiated with this factory.
|
|
* @internal
|
|
*/
|
|
static void _registerFactory(const UnicodeString& id,
|
|
Factory factory,
|
|
Token context);
|
|
|
|
/**
|
|
* @internal
|
|
*/
|
|
static void _registerInstance(Transliterator* adoptedObj);
|
|
|
|
/**
|
|
* @internal
|
|
*/
|
|
static void _registerAlias(const UnicodeString& aliasID, const UnicodeString& realID);
|
|
|
|
/**
|
|
* Register two targets as being inverses of one another. For
|
|
* example, calling registerSpecialInverse("NFC", "NFD", true) causes
|
|
* Transliterator to form the following inverse relationships:
|
|
*
|
|
* <pre>NFC => NFD
|
|
* Any-NFC => Any-NFD
|
|
* NFD => NFC
|
|
* Any-NFD => Any-NFC</pre>
|
|
*
|
|
* (Without the special inverse registration, the inverse of NFC
|
|
* would be NFC-Any.) Note that NFD is shorthand for Any-NFD, but
|
|
* that the presence or absence of "Any-" is preserved.
|
|
*
|
|
* <p>The relationship is symmetrical; registering (a, b) is
|
|
* equivalent to registering (b, a).
|
|
*
|
|
* <p>The relevant IDs must still be registered separately as
|
|
* factories or classes.
|
|
*
|
|
* <p>Only the targets are specified. Special inverses always
|
|
* have the form Any-Target1 <=> Any-Target2. The target should
|
|
* have canonical casing (the casing desired to be produced when
|
|
* an inverse is formed) and should contain no whitespace or other
|
|
* extraneous characters.
|
|
*
|
|
* @param target the target against which to register the inverse
|
|
* @param inverseTarget the inverse of target, that is
|
|
* Any-target.getInverse() => Any-inverseTarget
|
|
* @param bidirectional if true, register the reverse relation
|
|
* as well, that is, Any-inverseTarget.getInverse() => Any-target
|
|
* @internal
|
|
*/
|
|
static void _registerSpecialInverse(const UnicodeString& target,
|
|
const UnicodeString& inverseTarget,
|
|
UBool bidirectional);
|
|
#endif /* U_HIDE_INTERNAL_API */
|
|
|
|
public:
|
|
|
|
/**
|
|
* Unregisters a transliterator or class. This may be either
|
|
* a system transliterator or a user transliterator or class.
|
|
* Any attempt to construct an unregistered transliterator based
|
|
* on its ID will fail.
|
|
*
|
|
* Because ICU may choose to cache Transliterators internally, this should
|
|
* be called during application shutdown, after all calls to
|
|
* Transliterator::createXXX to avoid undefined behavior.
|
|
*
|
|
* @param ID the ID of the transliterator or class
|
|
* @return the <code>Object</code> that was registered with
|
|
* <code>ID</code>, or <code>null</code> if none was
|
|
* @see #registerInstance
|
|
* @see #registerFactory
|
|
* @stable ICU 2.0
|
|
*/
|
|
static void U_EXPORT2 unregister(const UnicodeString& ID);
|
|
|
|
public:
|
|
|
|
/**
|
|
* Return a StringEnumeration over the IDs available at the time of the
|
|
* call, including user-registered IDs.
|
|
* @param ec input-output error code
|
|
* @return a newly-created StringEnumeration over the transliterators
|
|
* available at the time of the call. The caller should delete this object
|
|
* when done using it.
|
|
* @stable ICU 3.0
|
|
*/
|
|
static StringEnumeration* U_EXPORT2 getAvailableIDs(UErrorCode& ec);
|
|
|
|
/**
|
|
* Return the number of registered source specifiers.
|
|
* @return the number of registered source specifiers.
|
|
* @stable ICU 2.0
|
|
*/
|
|
static int32_t U_EXPORT2 countAvailableSources(void);
|
|
|
|
/**
|
|
* Return a registered source specifier.
|
|
* @param index which specifier to return, from 0 to n-1, where
|
|
* n = countAvailableSources()
|
|
* @param result fill-in paramter to receive the source specifier.
|
|
* If index is out of range, result will be empty.
|
|
* @return reference to result
|
|
* @stable ICU 2.0
|
|
*/
|
|
static UnicodeString& U_EXPORT2 getAvailableSource(int32_t index,
|
|
UnicodeString& result);
|
|
|
|
/**
|
|
* Return the number of registered target specifiers for a given
|
|
* source specifier.
|
|
* @param source the given source specifier.
|
|
* @return the number of registered target specifiers for a given
|
|
* source specifier.
|
|
* @stable ICU 2.0
|
|
*/
|
|
static int32_t U_EXPORT2 countAvailableTargets(const UnicodeString& source);
|
|
|
|
/**
|
|
* Return a registered target specifier for a given source.
|
|
* @param index which specifier to return, from 0 to n-1, where
|
|
* n = countAvailableTargets(source)
|
|
* @param source the source specifier
|
|
* @param result fill-in paramter to receive the target specifier.
|
|
* If source is invalid or if index is out of range, result will
|
|
* be empty.
|
|
* @return reference to result
|
|
* @stable ICU 2.0
|
|
*/
|
|
static UnicodeString& U_EXPORT2 getAvailableTarget(int32_t index,
|
|
const UnicodeString& source,
|
|
UnicodeString& result);
|
|
|
|
/**
|
|
* Return the number of registered variant specifiers for a given
|
|
* source-target pair.
|
|
* @param source the source specifiers.
|
|
* @param target the target specifiers.
|
|
* @stable ICU 2.0
|
|
*/
|
|
static int32_t U_EXPORT2 countAvailableVariants(const UnicodeString& source,
|
|
const UnicodeString& target);
|
|
|
|
/**
|
|
* Return a registered variant specifier for a given source-target
|
|
* pair.
|
|
* @param index which specifier to return, from 0 to n-1, where
|
|
* n = countAvailableVariants(source, target)
|
|
* @param source the source specifier
|
|
* @param target the target specifier
|
|
* @param result fill-in paramter to receive the variant
|
|
* specifier. If source is invalid or if target is invalid or if
|
|
* index is out of range, result will be empty.
|
|
* @return reference to result
|
|
* @stable ICU 2.0
|
|
*/
|
|
static UnicodeString& U_EXPORT2 getAvailableVariant(int32_t index,
|
|
const UnicodeString& source,
|
|
const UnicodeString& target,
|
|
UnicodeString& result);
|
|
|
|
protected:
|
|
|
|
#ifndef U_HIDE_INTERNAL_API
|
|
/**
|
|
* Non-mutexed internal method
|
|
* @internal
|
|
*/
|
|
static int32_t _countAvailableSources(void);
|
|
|
|
/**
|
|
* Non-mutexed internal method
|
|
* @internal
|
|
*/
|
|
static UnicodeString& _getAvailableSource(int32_t index,
|
|
UnicodeString& result);
|
|
|
|
/**
|
|
* Non-mutexed internal method
|
|
* @internal
|
|
*/
|
|
static int32_t _countAvailableTargets(const UnicodeString& source);
|
|
|
|
/**
|
|
* Non-mutexed internal method
|
|
* @internal
|
|
*/
|
|
static UnicodeString& _getAvailableTarget(int32_t index,
|
|
const UnicodeString& source,
|
|
UnicodeString& result);
|
|
|
|
/**
|
|
* Non-mutexed internal method
|
|
* @internal
|
|
*/
|
|
static int32_t _countAvailableVariants(const UnicodeString& source,
|
|
const UnicodeString& target);
|
|
|
|
/**
|
|
* Non-mutexed internal method
|
|
* @internal
|
|
*/
|
|
static UnicodeString& _getAvailableVariant(int32_t index,
|
|
const UnicodeString& source,
|
|
const UnicodeString& target,
|
|
UnicodeString& result);
|
|
#endif /* U_HIDE_INTERNAL_API */
|
|
|
|
protected:
|
|
|
|
/**
|
|
* Set the ID of this transliterators. Subclasses shouldn't do
|
|
* this, unless the underlying script behavior has changed.
|
|
* @param id the new id t to be set.
|
|
* @stable ICU 2.4
|
|
*/
|
|
void setID(const UnicodeString& id);
|
|
|
|
public:
|
|
|
|
/**
|
|
* Return the class ID for this class. This is useful only for
|
|
* comparing to a return value from getDynamicClassID().
|
|
* Note that Transliterator is an abstract base class, and therefor
|
|
* no fully constructed object will have a dynamic
|
|
* UCLassID that equals the UClassID returned from
|
|
* TRansliterator::getStaticClassID().
|
|
* @return The class ID for class Transliterator.
|
|
* @stable ICU 2.0
|
|
*/
|
|
static UClassID U_EXPORT2 getStaticClassID(void);
|
|
|
|
/**
|
|
* Returns a unique class ID <b>polymorphically</b>. This method
|
|
* is to implement a simple version of RTTI, since not all C++
|
|
* compilers support genuine RTTI. Polymorphic operator==() and
|
|
* clone() methods call this method.
|
|
*
|
|
* <p>Concrete subclasses of Transliterator must use the
|
|
* UOBJECT_DEFINE_RTTI_IMPLEMENTATION macro from
|
|
* uobject.h to provide the RTTI functions.
|
|
*
|
|
* @return The class ID for this object. All objects of a given
|
|
* class have the same class ID. Objects of other classes have
|
|
* different class IDs.
|
|
* @stable ICU 2.0
|
|
*/
|
|
virtual UClassID getDynamicClassID(void) const = 0;
|
|
|
|
private:
|
|
static UBool initializeRegistry(UErrorCode &status);
|
|
|
|
public:
|
|
#ifndef U_HIDE_OBSOLETE_API
|
|
/**
|
|
* Return the number of IDs currently registered with the system.
|
|
* To retrieve the actual IDs, call getAvailableID(i) with
|
|
* i from 0 to countAvailableIDs() - 1.
|
|
* @return the number of IDs currently registered with the system.
|
|
* @obsolete ICU 3.4 use getAvailableIDs() instead
|
|
*/
|
|
static int32_t U_EXPORT2 countAvailableIDs(void);
|
|
|
|
/**
|
|
* Return the index-th available ID. index must be between 0
|
|
* and countAvailableIDs() - 1, inclusive. If index is out of
|
|
* range, the result of getAvailableID(0) is returned.
|
|
* @param index the given ID index.
|
|
* @return the index-th available ID. index must be between 0
|
|
* and countAvailableIDs() - 1, inclusive. If index is out of
|
|
* range, the result of getAvailableID(0) is returned.
|
|
* @obsolete ICU 3.4 use getAvailableIDs() instead; this function
|
|
* is not thread safe, since it returns a reference to storage that
|
|
* may become invalid if another thread calls unregister
|
|
*/
|
|
static const UnicodeString& U_EXPORT2 getAvailableID(int32_t index);
|
|
#endif /* U_HIDE_OBSOLETE_API */
|
|
};
|
|
|
|
inline int32_t Transliterator::getMaximumContextLength(void) const {
|
|
return maximumContextLength;
|
|
}
|
|
|
|
inline void Transliterator::setID(const UnicodeString& id) {
|
|
ID = id;
|
|
// NUL-terminate the ID string, which is a non-aliased copy.
|
|
ID.append((char16_t)0);
|
|
ID.truncate(ID.length()-1);
|
|
}
|
|
|
|
#ifndef U_HIDE_INTERNAL_API
|
|
inline Transliterator::Token Transliterator::integerToken(int32_t i) {
|
|
Token t;
|
|
t.integer = i;
|
|
return t;
|
|
}
|
|
|
|
inline Transliterator::Token Transliterator::pointerToken(void* p) {
|
|
Token t;
|
|
t.pointer = p;
|
|
return t;
|
|
}
|
|
#endif /* U_HIDE_INTERNAL_API */
|
|
|
|
U_NAMESPACE_END
|
|
|
|
#endif /* #if !UCONFIG_NO_TRANSLITERATION */
|
|
|
|
#endif /* U_SHOW_CPLUSPLUS_API */
|
|
|
|
#endif
|