throw new UnsupportedOperationException("getStartPosition() is not supported in this implementation");
        }

        @Override
        public int getOffset() {
            throw new UnsupportedOperationException("getOffset() is not supported in this implementation");
        }

        @Override
        public int getPageSize() {

        }
        final int pageSize = params.getPageSize();
        final int startPosition = params.getStartPosition();
        if (startPosition * 2 >= windowSize) {
            int offset = params.getOffset();
            if (offset < 0) {
                offset = 0;
            } else if (offset > windowSize / 2) {
                offset = windowSize / 2;
            }
            int start = startPosition - offset;