src/main/java/org/efaps/ui/wicket/components/tree/SortHeaderColumnLink.java
@Override
    public void onComponentTagBody(final MarkupStream _markupStream,
                                      final ComponentTag _openTag)
    {
        replaceComponentTagBody(_markupStream, _openTag, this.header);
    }
@Override
    public void onComponentTagBody(final MarkupStream _markupStream,
                                      final ComponentTag _openTag)
    {
        replaceComponentTagBody(_markupStream, _openTag, this.header);
    }
The body of the component is filled with the header.

@param _markupStream MarkupStream
@param _openTag ComponentTag