Java tutorial
/** * Copyright (c) 2009--2014 Red Hat, Inc. * * This software is licensed to you under the GNU General Public License, * version 2 (GPLv2). There is NO WARRANTY for this software, express or * implied, including the implied warranties of MERCHANTABILITY or FITNESS * FOR A PARTICULAR PURPOSE. You should have received a copy of GPLv2 * along with this software; if not, see * http://www.gnu.org/licenses/old-licenses/gpl-2.0.txt. * * Red Hat trademarks are not licensed under GPLv2. No permission is * granted to use or replicate Red Hat trademarks that are incorporated * in this software or its documentation. */ package com.redhat.rhn.frontend.action.channel.ssm; import com.redhat.rhn.common.db.datasource.DataResult; import com.redhat.rhn.domain.rhnset.RhnSet; import com.redhat.rhn.domain.user.User; import com.redhat.rhn.frontend.dto.ChildChannelDto; import com.redhat.rhn.frontend.dto.EssentialServerDto; import com.redhat.rhn.frontend.dto.SystemsPerChannelDto; import com.redhat.rhn.frontend.struts.RequestContext; import com.redhat.rhn.frontend.struts.RhnAction; import com.redhat.rhn.frontend.struts.RhnHelper; import com.redhat.rhn.frontend.taglibs.list.ListTagHelper; import com.redhat.rhn.manager.channel.ChannelManager; import com.redhat.rhn.manager.rhnset.RhnSetDecl; import com.redhat.rhn.manager.rhnset.RhnSetManager; import com.redhat.rhn.manager.system.SystemManager; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import org.apache.struts.action.ActionForm; import org.apache.struts.action.ActionForward; import org.apache.struts.action.ActionMapping; import org.apache.struts.action.DynaActionForm; import java.util.ArrayList; import java.util.Enumeration; import java.util.HashSet; import java.util.List; import java.util.Set; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; /** * ChildChannelAction * @version $Rev$ */ public class ChildChannelAction extends RhnAction { private final Log log = LogFactory.getLog(this.getClass()); /** * {@inheritDoc} */ @Override public ActionForward execute(ActionMapping mapping, ActionForm form, HttpServletRequest request, HttpServletResponse response) throws Exception { RequestContext rctx = new RequestContext(request); User user = rctx.getCurrentUser(); DynaActionForm daForm = (DynaActionForm) form; request.setAttribute(ListTagHelper.PARENT_URL, request.getRequestURI()); // Provide the list of all child-channels for all systems in the SSM setupList(user, request); // If submitted, save the user's choices for the confirm page if (isSubmitted(daForm) && request.getParameter("dispatch") != null) { if (processList(user, request) == 0) { createSuccessMessage(request, "ssmchildsubconfirm.jsp.noSystems", null); return mapping.findForward(RhnHelper.DEFAULT_FORWARD); } return mapping.findForward("success"); } return mapping.findForward(RhnHelper.DEFAULT_FORWARD); } // Get the list of child-channels available to the System Set // and create a data-structure mapping them to their respective base-channels protected void setupList(User user, HttpServletRequest request) { List<ChildChannelDto> children = ChannelManager.childrenAvailableToSet(user); List<SystemsPerChannelDto> bases = ChannelManager.baseChannelsInSet(user); request.setAttribute("bases", bases); int debugFound = 0; Set<ChildChannelDto> nullParented = new HashSet<ChildChannelDto>(); // Build a map of parents-to-children // (the combinatorics of this algorithm aren't very good, there is // room for a little optimisation here for (SystemsPerChannelDto systemsPerChannelDto : bases) { List<ChildChannelDto> availableChildren = new ArrayList<ChildChannelDto>(); systemsPerChannelDto.setAvailableChildren(availableChildren); // Find all the children for "this" parent for (ChildChannelDto childChannelDto : children) { if (childChannelDto.getParentId() == null) { if (!nullParented.contains(childChannelDto)) { nullParented.add(childChannelDto); debugFound++; } } else if (childChannelDto.getParentId().equals(systemsPerChannelDto.getId())) { DataResult<EssentialServerDto> sis = SystemManager.systemsSubscribedToChannelInSet( childChannelDto.getId().longValue(), user, RhnSetDecl.SYSTEMS.getLabel()); childChannelDto.setSystemCount(0L + sis.size()); availableChildren.add(childChannelDto); debugFound++; } } } if (debugFound != children.size()) { log.error("Did not process an equal number of children originally found. " + "Children: " + children.size() + ", Found: " + debugFound); } } /** * Processes the submitted parameters to determine which channels are being * subscribed, unsubscribed, or ignored. The first two sets will be stored as * RhnSets for later usage. * * @param user user making the request * @param request http request to grab the user submitted data from */ protected int processList(User user, HttpServletRequest request) { List<String> subList = new ArrayList<String>(); List<String> unsubList = new ArrayList<String>(); Enumeration<String> names = request.getParameterNames(); while (names.hasMoreElements()) { String aName = names.nextElement(); String aValue = request.getParameter(aName); if ("subscribe".equals(aValue)) { subList.add(aName); } else if ("unsubscribe".equals(aValue)) { unsubList.add(aName); } } storeChannelChanges(user, subList, unsubList); return subList.size() + unsubList.size(); } /** * Stores the user-selected lists of channels to (un)subscribe to in RhnSets * to be used later. * * @param user user making the request * @param subs subscriptions to be created * @param unsubs subscriptions to be removed */ protected void storeChannelChanges(User user, List<String> subs, List<String> unsubs) { RhnSet cset = RhnSetDecl.SSM_CHANNEL_LIST.create(user); cset.clear(); for (String idStr : subs) { try { Long id = Long.parseLong(idStr); cset.addElement(id, ChannelActionDAO.SUBSCRIBE); } catch (NumberFormatException nfe) { // Should never get here log.error("Attempting to parse a channel id from: " + idStr, nfe); } } for (String idStr : unsubs) { try { Long id = Long.parseLong(idStr); cset.addElement(id, ChannelActionDAO.UNSUBSCRIBE); } catch (NumberFormatException nfe) { // Should never get here log.error("Attempting to parse a channel id from: " + idStr, nfe); } } RhnSetManager.store(cset); } }