public StandardFilter(TokenStream in) 
{
    super(in);
}

Construct filtering in.

 public final Token next(Token result) throws IOException 
{
                           
    Token t = input.next(result);
    if (t == null)
      return null;
    char[] buffer = t.termBuffer();
    final int bufferLength = t.termLength();
    final String type = t.type();
    if (type == APOSTROPHE_TYPE &&		  // remove 's
	bufferLength  >= 2 &&
        buffer[bufferLength-2] == '\'" &&
        (buffer[bufferLength-1] == 's" || buffer[bufferLength-1] == 'S")) {
      // Strip last 2 characters off
      t.setTermLength(bufferLength - 2);
    } else if (type == ACRONYM_TYPE) {		  // remove dots
      int upto = 0;
      for(int i=0;i< bufferLength;i++) {
        char c = buffer[i];
        if (c != '.")
          buffer[upto++] = c;
      }
      t.setTermLength(upto);
    }
    return t;
}

Returns the next token in the stream, or null at EOS.

Removes 's from the end of words.

Removes dots from acronyms.