/*
* Copyright (c) 2009, 2010, 2011, 2012, 2013, 2014, B3log Team
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.b3log.solo.service;
import java.util.List;
import javax.inject.Inject;
import org.b3log.latke.Keys;
import org.b3log.latke.logging.Level;
import org.b3log.latke.logging.Logger;
import org.b3log.latke.model.Pagination;
import org.b3log.latke.repository.Query;
import org.b3log.latke.repository.SortDirection;
import org.b3log.latke.service.ServiceException;
import org.b3log.latke.service.annotation.Service;
import org.b3log.latke.util.Paginator;
import org.b3log.solo.model.Link;
import org.b3log.solo.repository.LinkRepository;
import org.json.JSONArray;
import org.json.JSONObject;
/**
* Link query service.
*
* @author <a href="http://88250.b3log.org">Liang Ding</a>
* @version 1.0.0.2, Oct 31, 2011
* @since 0.4.0
*/
@Service
public class LinkQueryService {
/**
* Logger.
*/
private static final Logger LOGGER = Logger.getLogger(LinkQueryService.class.getName());
/**
* Link repository.
*/
@Inject
private LinkRepository linkRepository;
/**
* Gets links by the specified request json object.
*
* @param requestJSONObject the specified request json object, for example,
* <pre>
* {
* "paginationCurrentPageNum": 1,
* "paginationPageSize": 20,
* "paginationWindowSize": 10
* }, see {@link Pagination} for more details
* </pre>
* @return for example,
* <pre>
* {
* "pagination": {
* "paginationPageCount": 100,
* "paginationPageNums": [1, 2, 3, 4, 5]
* },
* "links": [{
* "oId": "",
* "linkTitle": "",
* "linkAddress": "",
* ""linkDescription": ""
* }, ....]
* }
* </pre>
* @throws ServiceException service exception
* @see Pagination
*/
public JSONObject getLinks(final JSONObject requestJSONObject) throws ServiceException {
final JSONObject ret = new JSONObject();
try {
final int currentPageNum = requestJSONObject.getInt(Pagination.PAGINATION_CURRENT_PAGE_NUM);
final int pageSize = requestJSONObject.getInt(Pagination.PAGINATION_PAGE_SIZE);
final int windowSize = requestJSONObject.getInt(Pagination.PAGINATION_WINDOW_SIZE);
final Query query = new Query().setCurrentPageNum(currentPageNum).setPageSize(pageSize).addSort(Link.LINK_ORDER,
SortDirection.ASCENDING);
final JSONObject result = linkRepository.get(query);
final int pageCount = result.getJSONObject(Pagination.PAGINATION).getInt(Pagination.PAGINATION_PAGE_COUNT);
final JSONObject pagination = new JSONObject();
final List<Integer> pageNums = Paginator.paginate(currentPageNum, pageSize, pageCount, windowSize);
pagination.put(Pagination.PAGINATION_PAGE_COUNT, pageCount);
pagination.put(Pagination.PAGINATION_PAGE_NUMS, pageNums);
final JSONArray links = result.getJSONArray(Keys.RESULTS);
ret.put(Pagination.PAGINATION, pagination);
ret.put(Link.LINKS, links);
return ret;
} catch (final Exception e) {
LOGGER.log(Level.ERROR, "Gets links failed", e);
throw new ServiceException(e);
}
}
/**
* Gets a link by the specified link id.
*
* @param linkId the specified link id
* @return for example,
* <pre>
* {
* "link": {
* "oId": "",
* "linkTitle": "",
* "linkAddress": "",
* "linkDescription": ""
* }
* }
* </pre>, returns {@code null} if not found
* @throws ServiceException service exception
*/
public JSONObject getLink(final String linkId) throws ServiceException {
final JSONObject ret = new JSONObject();
try {
final JSONObject link = linkRepository.get(linkId);
if (null == link) {
return null;
}
ret.put(Link.LINK, link);
return ret;
} catch (final Exception e) {
LOGGER.log(Level.ERROR, "Gets a link failed", e);
throw new ServiceException(e);
}
}
/**
* Sets the link repository with the specified link repository.
*
* @param linkRepository the specified link repository
*/
public void setLinkRepository(final LinkRepository linkRepository) {
this.linkRepository = linkRepository;
}
}