1// Copyright (C) 2016 and later: Unicode, Inc. and others.
2// License & terms of use: http://www.unicode.org/copyright.html
3/*
4 **********************************************************************
5 *   Copyright (c) 2001-2007, International Business Machines
6 *   Corporation and others.  All Rights Reserved.
7 **********************************************************************
8 *   Date        Name        Description
9 *   11/20/2001  aliu        Creation.
10 **********************************************************************
11 */
12#ifndef UNESCTRN_H
13#define UNESCTRN_H
14
15#include "unicode/utypes.h"
16
17#if !UCONFIG_NO_TRANSLITERATION
18
19#include "unicode/translit.h"
20
21U_NAMESPACE_BEGIN
22
23/**
24 * A transliterator that converts Unicode escape forms to the
25 * characters they represent.  Escape forms have a prefix, a suffix, a
26 * radix, and minimum and maximum digit counts.
27 *
28 * <p>This class is package private.  It registers several standard
29 * variants with the system which are then accessed via their IDs.
30 *
31 * @author Alan Liu
32 */
33class UnescapeTransliterator : public Transliterator {
34
35 private:
36
37    /**
38     * The encoded pattern specification.  The pattern consists of
39     * zero or more forms.  Each form consists of a prefix, suffix,
40     * radix, minimum digit count, and maximum digit count.  These
41     * values are stored as a five character header.  That is, their
42     * numeric values are cast to 16-bit characters and stored in the
43     * string.  Following these five characters, the prefix
44     * characters, then suffix characters are stored.  Each form thus
45     * takes n+5 characters, where n is the total length of the prefix
46     * and suffix.  The end is marked by a header of length one
47     * consisting of the character END.
48     */
49    UChar* spec; // owned; may not be NULL
50
51 public:
52
53    /**
54     * Registers standard variants with the system.  Called by
55     * Transliterator during initialization.
56     */
57    static void registerIDs();
58
59    /**
60     * Constructor.  Takes the encoded spec array (does not adopt it).
61     * @param ID   the string identifier for this transliterator
62     * @param spec the encoded spec array
63     */
64    UnescapeTransliterator(const UnicodeString& ID,
65                           const UChar *spec);
66
67    /**
68     * Copy constructor.
69     */
70    UnescapeTransliterator(const UnescapeTransliterator&);
71
72    /**
73     * Destructor.
74     */
75    virtual ~UnescapeTransliterator();
76
77    /**
78     * Transliterator API.
79     */
80    virtual Transliterator* clone() const;
81
82    /**
83     * ICU "poor man's RTTI", returns a UClassID for the actual class.
84     */
85    virtual UClassID getDynamicClassID() const;
86
87    /**
88     * ICU "poor man's RTTI", returns a UClassID for this class.
89     */
90    U_I18N_API static UClassID U_EXPORT2 getStaticClassID();
91
92 protected:
93
94    /**
95     * Implements {@link Transliterator#handleTransliterate}.
96     * @param text        the buffer holding transliterated and
97     *                    untransliterated text
98     * @param offset      the start and limit of the text, the position
99     *                    of the cursor, and the start and limit of transliteration.
100     * @param incremental if true, assume more text may be coming after
101     *                    pos.contextLimit.  Otherwise, assume the text is complete.
102     */
103    virtual void handleTransliterate(Replaceable& text, UTransPosition& offset,
104                             UBool isIncremental) const;
105
106};
107
108U_NAMESPACE_END
109
110#endif /* #if !UCONFIG_NO_TRANSLITERATION */
111
112#endif
113