Package org.apache.commons.text.matcher

## Interface StringMatcher

-     public interface StringMatcher

  Determines if a character array portion matches.
  Since:
    1.3

- - ### Method Summary

    All Methods Instance Methods Abstract Methods
    Modifier and Type | Method | Description
    --- | --- | ---
    `int` | `isMatch​(char[] buffer, int pos, int bufferStart, int bufferEnd)` | Returns the number of matching characters, zero for no match.

- - ### Method Detail

    - #### isMatch

          int isMatch​(char[] buffer,
                      int pos,
                      int bufferStart,
                      int bufferEnd)

      Returns the number of matching characters, zero for no match.

      This method is called to check for a match. The parameter `pos` represents the current position to be checked in the string `buffer` (a character array which must not be changed). The API guarantees that `pos` is a valid index for `buffer`.

      The character array may be larger than the active area to be matched. Only values in the buffer between the specified indices may be accessed.

      The matching code may check one character or many. It may check characters preceding `pos` as well as those after, so long as no checks exceed the bounds specified.

      It must return zero for no match, or a positive number if a match was found. The number indicates the number of characters that matched.

      Parameters:
        `buffer` - the text content to match against, do not change
        `pos` - the starting position for the match, valid for buffer
        `bufferStart` - the first active index in the buffer, valid for buffer
        `bufferEnd` - the end index (exclusive) of the active buffer, valid for buffer
      Returns:
        the number of matching characters, or zero if there is no match