this.hostIndex = max(0, this.hostIndex);
this.hostIndex = min(this.hostIndex, this.hostSize - 1);
int endIndex = min(this.hostIndex + TopologyPresenter.VISIBLE_HOSTS_COLUMNS, hostSize);
// start table and add columns
html.startTable().appendHtmlConstant("<colgroup>");
int columnWidth = HOSTS_COLUMNS / (endIndex - this.hostIndex);
html.appendColumn(SERVER_GROUPS_COLUMN);
for (int i = this.hostIndex; i < endIndex; i++) {
html.appendColumn(columnWidth);
}