sun.text.normalizer
Interface Replaceable

All Known Implementing Classes:

ReplaceableString

public interface Replaceable

Replaceable is an interface 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 metadata. Metadata is data other than the Unicode characters returned by char32At(). One example of metadata is style attributes; another is an edit history, marking each character with an author and revision number.

An implicit aspect of the Replaceable API is that during a replace operation, new characters take on the metadata of the old characters. For example, if the string "the bold font" has range (4, 8) replaced with "strong", then it becomes "the strong font".

Replaceable specifies ranges using a start offset and a limit offset. The range of characters thus specified includes the characters at offset start..limit-1. That is, the start offset is inclusive, and the limit offset is exclusive.

Replaceable also includes API to access characters in the string: length(), charAt(), char32At(), and extractBetween().

For a subclass to support metadata, typical behavior of replace() is the following:

• Set the metadata of the new text to the metadata of the first character replaced
• If no characters are replaced, use the metadata of the previous character
• If there is no previous character (i.e. start == 0), use the following character
• If there is no following character (i.e. the replaceable was empty), use default metadata
  
• If the code point U+FFFF is seen, it should be interpreted as a special marker having no metadata

If this is not the behavior, the subclass should document any differences.

Copyright © IBM Corporation 1999. All rights reserved.

Method Summary

char	charAt(int offset) Returns the 16-bit code unit at the given offset into the text.
void	getChars(int srcStart, int srcLimit, char[] dst, int dstStart) Copies characters from this object into the destination character array.
int	length() Returns the number of 16-bit code units in the text.

Method Detail

length

int length()

Returns the number of 16-bit code units in the text.

Returns:

number of 16-bit code units in text

charAt

char charAt(int offset)

Returns the 16-bit code unit at the given offset into the text.

Parameters:

offset - an integer between 0 and length()-1 inclusive

Returns:

16-bit code unit of text at given offset

getChars

void getChars(int srcStart,
              int srcLimit,
              char[] dst,
              int dstStart)

Copies characters from this object into the destination character array. The first character to be copied is at index srcStart; the last character to be copied is at index srcLimit-1 (thus the total number of characters to be copied is srcLimit-srcStart). The characters are copied into the subarray of dst starting at index dstStart and ending at index dstStart + (srcLimit-srcStart) - 1.

Parameters:

srcStart - the beginning index to copy, inclusive; 0 <= start <= limit.

srcLimit - the ending index to copy, exclusive; start <= limit <= length().

dst - the destination array.

dstStart - the start offset in the destination array.