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