How to get the bookmark information when creating a table of contents.

I have setted bookmarks in the content, how can I collect the bookmarks in the table of content page. I've set  the part property net.sf.jasperreports.bookmarks.data.source.parameter, value = "REPORT_DATA_SOURCE"。Then how can I get the three fields that representing the bookmarks: $F{label},$F{level} and $F{pageindex}?