import javax.swing.text.Segment;

Stack stack = new Stack();
Segment lineText = new Segment();

for (int line=0; line<buffer.getLineCount(); line++) {
  DefaultTokenHandler tokenHandler = new DefaultTokenHandler();
  buffer.markTokens(line,tokenHandler);
  Token token = tokenHandler.getTokens();
  int lineOffset = buffer.getLineStartOffset(line);
  while(token.id != Token.END) {
  	if(token.id == Token.OPERATOR) {
      buffer.getLineText(line,lineText);
      char operator = lineText.array[lineText.offset + token.offset];
      if(operator == '{') {
        stack.push(lineOffset + token.offset);
      } else if(operator == '}') {
        if(!stack.isEmpty()) {
          stack.pop();
        } else {
          textArea.setCaretPosition(lineOffset + token.offset);
          return;
        }
      }
  	}
    token = token.next;
  } 
}

if(!stack.isEmpty()) {
  textArea.setCaretPosition(stack.pop());
}