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.configuration; import com.redhat.rhn.domain.config.ConfigChannel; import com.redhat.rhn.domain.rhnset.RhnSet; import com.redhat.rhn.domain.rhnset.RhnSetElement; import com.redhat.rhn.domain.user.User; import com.redhat.rhn.frontend.struts.RequestContext; import com.redhat.rhn.frontend.struts.RhnHelper; import com.redhat.rhn.frontend.struts.RhnLookupDispatchAction; import com.redhat.rhn.manager.configuration.ConfigurationManager; import com.redhat.rhn.manager.rhnset.RhnSetDecl; import org.apache.commons.lang.StringUtils; 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 org.apache.struts.util.LabelValueBean; import java.util.ArrayList; import java.util.HashMap; import java.util.Iterator; import java.util.LinkedHashSet; import java.util.List; import java.util.Map; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; /** * BaseRankChannels, Abstract class for config channel rankings in ssm and sdc. * @version $Rev$ */ public abstract class BaseRankChannels extends RhnLookupDispatchAction { protected static final String POSSIBLE_CHANNELS = "possibleChannels"; protected static final String SELECTED_CHANNEL = "selectedChannel"; protected static final String RANKED_VALUES = "rankedValues"; /** * Sets up the rangling widget. * @param context the request context of the current request * @param form the dynaform related to the current request. * @param set the rhnset holding the channel ids. */ protected void setupWidget(RequestContext context, DynaActionForm form, RhnSet set) { User user = context.getCurrentUser(); LinkedHashSet labelValues = new LinkedHashSet(); populateWidgetLabels(labelValues, context); for (Iterator itr = set.getElements().iterator(); itr.hasNext();) { Long ccid = ((RhnSetElement) itr.next()).getElement(); ConfigChannel channel = ConfigurationManager.getInstance().lookupConfigChannel(user, ccid); labelValues.add(lv(channel.getName(), channel.getId().toString())); } //set the form variables for the widget to read. form.set(POSSIBLE_CHANNELS, labelValues); if (!labelValues.isEmpty()) { if (form.get(SELECTED_CHANNEL) == null) { String selected = ((LabelValueBean) labelValues.iterator().next()).getValue(); form.set(SELECTED_CHANNEL, selected); } } } /** * Extension point for each of the subclasses to add content * LabelValues before more content is added to it using rhn sets * to the RankWidget check box.. * The subclasses should update the labelValues * @param labelValues a LinkedHashSet/List in some sense that * holds a bunch of lv(Channel labels, Channel ids). * This is a Linked Hash Set becasue we needed to * throw away duplicate insertions while maintaining * the correct order of insertion. * @param context the request context of the current request */ protected abstract void populateWidgetLabels(LinkedHashSet labelValues, RequestContext context); /** * Returns the the channel Ids info retrieved after one * has clicked Update Channel Rankings or Apply Subscriptions. * @param form the submitted form.. * @return List containing the channel ids in the order of * their new rankings. */ protected List getChannelIds(DynaActionForm form) { List channels = new ArrayList(); String rankedValues = (String) form.get(RANKED_VALUES); if (StringUtils.isNotBlank(rankedValues)) { String[] values = rankedValues.split(","); for (int i = 0; i < values.length; i++) { channels.add(new Long(values[i])); } } return channels; } /** * returns the Rhn Set used to store the sets.. * @param user The Loggin User * @return rhn set used to store channel ids. */ protected RhnSet getRhnSet(User user) { return RhnSetDecl.CONFIG_CHANNELS_RANKING.get(user); } /** * * Raises an error message saying javascript is required * to process this page * @param mapping struts ActionMapping * @param formIn struts ActionForm * @param request HttpServletRequest * @param response HttpServletResponse * @return An action forward to the default page with the error message */ public ActionForward handleNoScript(ActionMapping mapping, ActionForm formIn, HttpServletRequest request, HttpServletResponse response) { RequestContext context = new RequestContext(request); if (!context.isJavaScriptEnabled()) { getStrutsDelegate().saveMessage("common.config.rank.jsp.error.nojavascript", request); } Map map = new HashMap(); processParams(context, map); User user = context.getCurrentUser(); RhnSet set = getRhnSet(user); setup(context, (DynaActionForm) formIn, set); return getStrutsDelegate().forwardParams(mapping.findForward(RhnHelper.DEFAULT_FORWARD), map); } /** * Extension points for each of the BaseRankChannel sub classses * to add params to forwarding page.. * @param context the request context of the current request. * @param params the params to be updated */ protected abstract void processParams(RequestContext context, Map params); /** * Extension point for doing additional setup stuff * before the jsp is loaded... * @param context the request context of the current request. * @param form the action form for setting up form contents on the new page * @param set the set storing the rank contents */ protected abstract void setup(RequestContext context, DynaActionForm form, RhnSet set); }