| /* |
| ************************************************************************** |
| * Copyright (C) 1999-2001, International Business Machines Corporation and |
| * others. All Rights Reserved. |
| ************************************************************************** |
| * Date Name Description |
| * 11/17/99 aliu Creation. Ported from java. Modified to |
| * match current UnicodeString API. Forced |
| * to use name "handleReplaceBetween" because |
| * of existing methods in UnicodeString. |
| ************************************************************************** |
| */ |
| |
| #ifndef REP_H |
| #define REP_H |
| |
| #include "unicode/utypes.h" |
| U_NAMESPACE_BEGIN |
| |
| class UnicodeString; |
| |
| /** |
| * <code>Replaceable</code> is an abstract base class representing a |
| * string of characters that supports the replacement of a range of |
| * itself with a new string of characters. It is used by APIs that |
| * change a piece of text while retaining style attributes. In other |
| * words, an implicit aspect of the <code>Replaceable</code> API is |
| * that during a replace operation, new characters take on the |
| * attributes, if any, of the old characters. For example, if the |
| * string "the <b>bold</b> font" has range (4, 8) replaced with |
| * "strong", then it becomes "the <b>strong</b> font". |
| * |
| * <p><code>Replaceable</code> specifies ranges using an initial |
| * offset and a limit offset. The range of characters thus specified |
| * includes the characters at offset initial..limit-1. That is, the |
| * start offset is inclusive, and the limit offset is exclusive. |
| * |
| * <p><code>Replaceable</code> also includes API to access characters |
| * in the string: <code>length()</code>, <code>charAt()</code>, and |
| * <code>extractBetween()</code>. |
| * |
| * <p>If a subclass supports styles, then typically the behavior is the following: |
| * <ul> |
| * <li>Set the styles to the style of the first character replaced</li> |
| * <li>If no characters are replaced, use the style of the previous |
| * character</li> |
| * <li>If there is no previous character (i.e. start == 0), use the following |
| * character</li> |
| * <li>If there is no following character (i.e. the replaceable was empty), a |
| * default style.<br> |
| * </li> |
| * </ul> |
| * If this is not the behavior, the subclass should document any differences. |
| * @author Alan Liu |
| * @stable |
| */ |
| class U_COMMON_API Replaceable { |
| |
| public: |
| /** |
| * Destructor. |
| * @stable |
| */ |
| virtual ~Replaceable(); |
| |
| /** |
| * Return the number of characters in the text. |
| * @return number of characters in text |
| * @draft ICU 1.8 |
| */ |
| inline int32_t length() const; |
| |
| /** |
| * Return the Unicode code unit at the given offset into the text. |
| * @param offset an integer between 0 and <code>length()</code>-1 |
| * inclusive |
| * @return code unit of text at given offset |
| * @draft ICU 1.8 |
| */ |
| inline UChar charAt(UTextOffset offset) const; |
| |
| /** |
| * Return the Unicode code point that contains the code unit |
| * at the given offset into the text. |
| * @param offset an integer between 0 and <code>length()</code>-1 |
| * inclusive that indicates the text offset of any of the code units |
| * that will be assembled into a code point (21-bit value) and returned |
| * @return code point of text at given offset |
| * @draft ICU 1.8 |
| */ |
| inline UChar32 char32At(UTextOffset offset) const; |
| |
| /** |
| * Copy characters from this object into the destination character |
| * array. The first character to be copied is at index |
| * <code>srcStart</code>; the last character to be copied is at |
| * index <code>srcLimit-1</code> (thus the total number of |
| * characters to be copied is <code>srcLimit-srcStart</code>). The |
| * characters are copied into the subarray of <code>dst</code> |
| * starting at index <code>dstStart</code> and ending at index |
| * <code>dstStart + (srcLimit-srcStart) - 1</code>. |
| * |
| * @param srcStart the beginning index to copy, inclusive; <code>0 |
| * <= srcStart <= srcLimit</code>. |
| * @param srcLimit the ending index to copy, exclusive; |
| * <code>srcStart <= srcLimit <= length()</code>. |
| * @param dst the destination array. |
| * @param dstStart the start offset in the destination array. |
| * @draft |
| */ |
| /* THIS API IS NOT NEEDED, BUT KEPT HERE AS A COMMENT IN |
| CASE OF FUTURE NEED. CURRENTLY INDIVIDUAL CHARACTER |
| ACCESS SUFFICES. */ |
| /* virtual void extractBetween(UTextOffset srcStart, |
| UTextOffset srcLimit, |
| UChar* dst, |
| UTextOffset dstStart = 0) const = 0; */ |
| |
| /** |
| * Replace a substring of this object with the given text. If the |
| * characters being replaced have attributes, the new characters |
| * that replace them should be given the same attributes. |
| * |
| * <p>Subclasses must ensure that if the text between start and |
| * limit is equal to the replacement text, that replace has no |
| * effect. That is, any out-of-band information such as styles |
| * should be unaffected. In addition, subclasses are encourage to |
| * check for initial and trailing identical characters, and make a |
| * smaller replacement if possible. This will preserve as much |
| * style information as possible. |
| * @param start the beginning index, inclusive; <code>0 <= start |
| * <= limit</code>. |
| * @param limit the ending index, exclusive; <code>start <= limit |
| * <= length()</code>. |
| * @param text the text to replace characters <code>start</code> |
| * to <code>limit - 1</code> |
| * @stable |
| */ |
| virtual void handleReplaceBetween(UTextOffset start, |
| UTextOffset limit, |
| const UnicodeString& text) = 0; |
| // Note: All other methods in this class take the names of |
| // existing UnicodeString methods. This method is the exception. |
| // It is named differently because all replace methods of |
| // UnicodeString return a UnicodeString&. The 'between' is |
| // required in order to conform to the UnicodeString naming |
| // convention; API taking start/length are named <operation>, and |
| // those taking start/limit are named <operationBetween>. The |
| // 'handle' is added because 'replaceBetween' and |
| // 'doReplaceBetween' are already taken. |
| |
| /** |
| * Copy a substring of this object, retaining attribute (out-of-band) |
| * information. This method is used to duplicate or reorder substrings. |
| * The destination index must not overlap the source range. |
| * Implementations that do not care about maintaining out-of-band |
| * information or performance during copying may use the naive |
| * implementation: |
| * |
| * <pre> char[] text = new char[limit - start]; |
| * getChars(start, limit, text, 0); |
| * replace(dest, dest, text, 0, limit - start);</pre> |
| * |
| * @param start the beginning index, inclusive; <code>0 <= start <= |
| * limit</code>. |
| * @param limit the ending index, exclusive; <code>start <= limit <= |
| * length()</code>. |
| * @param dest the destination index. The characters from |
| * <code>start..limit-1</code> will be copied to <code>dest</code>. |
| * Implementations of this method may assume that <code>dest <= start || |
| * dest >= limit</code>. |
| * @stable */ |
| virtual void copy(int32_t start, int32_t limit, int32_t dest) = 0; |
| |
| protected: |
| |
| /** |
| * Default constructor. |
| */ |
| Replaceable(); |
| |
| /** |
| * Virtual version of length(). |
| */ |
| virtual int32_t getLength() const = 0; |
| |
| /** |
| * Virtual version of charAt(). |
| */ |
| virtual UChar getCharAt(UTextOffset offset) const = 0; |
| |
| /** |
| * Virtual version of char32At(). |
| */ |
| virtual UChar32 getChar32At(UTextOffset offset) const = 0; |
| }; |
| |
| inline Replaceable::Replaceable() {} |
| |
| inline Replaceable::~Replaceable() {} |
| |
| inline int32_t |
| Replaceable::length() const { |
| return getLength(); |
| } |
| |
| inline UChar |
| Replaceable::charAt(UTextOffset offset) const { |
| return getCharAt(offset); |
| } |
| |
| inline UChar32 |
| Replaceable::char32At(UTextOffset offset) const { |
| return getChar32At(offset); |
| } |
| |
| U_NAMESPACE_END |
| |
| #endif |