com.ibm.icu.text
Interface Replaceable

All Known Implementing Classes:
ReplaceableString

public interface Replaceable

Replaceable is an interface that supports the operation of replacing a substring with another piece of text. Replaceable is needed in order to change a piece of text while retaining style attributes. For example, if the string "the bold font" has range (4, 8) replaced with "strong", then it becomes "the strong font".

If a subclass supports styles, then typically the behavior is the following:

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

Copyright © IBM Corporation 1999. All rights reserved.

Version:
$RCSfile: Replaceable.java,v $ $Revision: 1.6 $ $Date: 2002/02/16 03:06:12 $
Author:
Alan Liu

Method Summary
 int char32At(int offset)
          Return the 32-bit code point at the given 16-bit offset into the text.
 char charAt(int offset)
          Return the character at the given offset into the text.
 void copy(int start, int limit, int dest)
          Copy a substring of this object, retaining attribute (out-of-band) information.
 void getChars(int srcStart, int srcLimit, char[] dst, int dstStart)
          Copies characters from this object into the destination character array.
 int length()
          Return the number of characters in the text.
 void replace(int start, int limit, char[] chars, int charsStart, int charsLen)
          Replace a substring of this object with the given text.
 void replace(int start, int limit, java.lang.String text)
          Replace a substring of this object with the given text.
 

Method Detail

length

public int length()
Return the number of characters in the text.
Returns:
number of characters in text

charAt

public char charAt(int offset)
Return the character at the given offset into the text.
Parameters:
offset - an integer between 0 and length()-1 inclusive
Returns:
character of text at given offset

char32At

public int char32At(int offset)
Return the 32-bit code point at the given 16-bit offset into the text. This assumes the text is stored as 16-bit code units with surrogate pairs intermixed. If the offset of a leading or trailing code unit of a surrogate pair is given, return the code point of the surrogate pair.

Most subclasses can return com.ibm.icu.text.UTF16.charAt(this, offset).

Parameters:
offset - an integer between 0 and length()-1 inclusive
Returns:
32-bit code point of text at given offset

getChars

public 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.

replace

public void replace(int start,
                    int limit,
                    java.lang.String text)
Replace a substring of this object with the given text.

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.

Parameters:
start - the beginning index, inclusive; 0 <= start <= limit.
limit - the ending index, exclusive; start <= limit <= length().
text - the text to replace characters start to limit - 1

replace

public void replace(int start,
                    int limit,
                    char[] chars,
                    int charsStart,
                    int charsLen)
Replace a substring of this object with the given text.

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.

Parameters:
start - the beginning index, inclusive; 0 <= start <= limit.
limit - the ending index, exclusive; start <= limit <= length().
chars - the text to replace characters start to limit - 1
charsStart - the beginning index into chars, inclusive; 0 <= start <= limit.
charsLen - the number of characters of chars.

copy

public void copy(int start,
                 int limit,
                 int dest)
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:
 char[] text = new char[limit - start];
 getChars(start, limit, text, 0);
 replace(dest, dest, text, 0, limit - start);
Parameters:
start - the beginning index, inclusive; 0 <= start <= limit.
limit - the ending index, exclusive; start <= limit <= length().
dest - the destination index. The characters from start..limit-1 will be copied to dest. Implementations of this method may assume that dest <= start || dest >= limit.


Copyright (c) 2001 IBM Corporation and others.