Apache Directory LDAP - Paged searches

Question

I've looking for information to perform paged searches using the Apache Directory API, but I haven't found any example or any information about how build a SearchRequest with the proper PagedResults control and then perform the search.

Any of you have some tip? Or knows where to find such information?

Or, maybe you should recommend me to use some other API, like unboundid sdk

Thanks in advance and kind regards.

Answer 1

Today I struggled with making the linked example from kayyagara work.

It has some problems:

• a special System Variable is needed, to make this work at all
• the bad cookie breaks the whole thing
• some settings/lines of code were not needed

The following is working example:

        //Without this you get a class Cast Exception:
        //java.lang.ClassCastException: org.apache.directory.api.ldap.codec.BasicControlDecorator cannot be cast to org.apache.directory.api.ldap.model.message.controls.PagedResults
        System.setProperty(StandaloneLdapApiService.CONTROLS_LIST,
            PagedResultsFactory.class.getName());

        PagedResults pagedSearchControl = new PagedResultsDecorator(
                connection.getCodecService());
        pagedSearchControl.setSize(300);

        // Loop over all the elements
        List<Entry> results = new ArrayList<Entry>();
        boolean hasUnwillingToPerform = false;

        //inspired by http://markmail.org/message/43qjepg6shvfvqud
        while (true) {
            EntryCursor cursor = null;

            try {
                SearchRequest searchRequest = new SearchRequestImpl();
                searchRequest.setBase(new Dn(searchRoot));
                searchRequest.setFilter(searchFilter);
                searchRequest.setScope(SearchScope.SUBTREE);
                searchRequest.addAttributes("*");
                searchRequest.addControl(pagedSearchControl);

                cursor = new EntryCursorImpl(
                        connection.search(searchRequest));

                while (cursor.next()) {
                    Entry result = cursor.get();
                    results.add(result);
                }

                SearchResultDone result = cursor.getSearchResultDone();
                pagedSearchControl = (PagedResults) result
                        .getControl(PagedResults.OID);

                if (result.getLdapResult().getResultCode() == ResultCodeEnum.UNWILLING_TO_PERFORM) {
                    hasUnwillingToPerform = true;
                    break;
                }
            } finally {
                if (cursor != null) {
                    cursor.close();
                }
            }

            // check if this is over
            byte[] cookie = pagedSearchControl.getCookie();

            if (Strings.isEmpty(cookie)) {
                // If so, exit the loop
                break;
            }

            // Prepare the next iteration
            pagedSearchControl.setSize(300);
        }

        if (hasUnwillingToPerform) {
            throw new IllegalStateException("AD can't handle paging");
        }

        // Cleanup the session
        connection.unBind();
        connection.close();