filterDocuments()method
takes in a RequestInfo object that contains the current HttpSerlvetRequest
object and an array of DocumentInfo objects and returns an array of
integers, indicating if the corresponding documents should be removed
from the result.
pruneSource()method
will be called as an optimization to prune an entire data source from
the query results.
filterBrowseFolders()method
takes an array of FolderInfo objects and returns an array of integers,
indicating whether the corresponding folders should be shown in the
browse page.
getCurrentUserName()
close()method
will be called once the object is no longer required so that any resource
that the object may have acquired can be released.