/*
* This library is part of OpenCms -
* the Open Source Content Management System
*
* Copyright (c) Alkacon Software GmbH (http://www.alkacon.com)
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* For further information about Alkacon Software GmbH, please see the
* company website: http://www.alkacon.com
*
* For further information about OpenCms, please see the
* project website: http://www.opencms.org
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
package org.opencms.workplace.tools.searchindex;
import org.opencms.search.CmsSearchParameters;
import java.util.Collection;
import java.util.LinkedList;
import java.util.List;
/**
* A hook on the list of categories of the <code>CmsSearchParameters</code>
* (see <code>{@link org.opencms.search.CmsSearchParameters#setCategories(List)}</code>)
* that will set the page to display of the search parameters to start (1) whenever
* a change in the amount of categories takes place. <p>
*
* This hook monitors the actions of the <code>{@link org.opencms.workplace.CmsWidgetDialog}</code>:
* During a request - response cycle it clears the list (prepareCommit)
* of categories and adds all request parameters (actionCommitValue) to the list. <p>
*
* The strategy here is to save all categories in a backup at "onClear" - time
* and then wait until all add operations are finished. This is when the iterator()
* method is triggered by the running search (<code>{@link org.opencms.search.CmsSearch#getSearchResult()}</code>).
* At that time it is detected wether we have "lost" categories. If this is the
* case, the search page will be reset to start. <p>
*
* <h3>Warning</h3>
* This procedure is highly unstable as coupled to the behaviour of CmsWidgetDialog. It
* will only be successful if the request parameter "action" has a value in
* <ol>
* <li>
* <code>{@link org.opencms.workplace.CmsWidgetDialog#DIALOG_SAVE}</code>
* </li>
* <li>
* <code>{@link org.opencms.workplace.CmsWidgetDialog#DIALOG_BACK}</code>
* </li>
* <li>
* <code>{@link org.opencms.workplace.CmsWidgetDialog#DIALOG_CONTINUE}</code>
* </li>
* </ol>
*
* Search page links (<code>{@link org.opencms.search.CmsSearch#getPageLinks()}</code>)
* contain a parameter "action" with value "search" which has to be rewritten to one
* of those values or the order of operations on widget - managed collections does not
* work together with the detection strategy for category changes used here. <p>
*
* @since 6.0.0
*/
public class CmsHookListSearchCategory extends CmsHookList {
private static final long serialVersionUID = 145986432425221213L;
/** The snapshot (clone) of this list at "clear()" time. **/
private List m_backupCategories;
/**
* @param peer the search parameters to modify upon category modifications.
*/
public CmsHookListSearchCategory(CmsSearchParameters peer) {
super(peer);
}
/**
* @param peer the search parameters to modify upon category modifications
*
* @param c a collection with all values for this list
*/
public CmsHookListSearchCategory(CmsSearchParameters peer, Collection c) {
super(peer, c);
}
/**
* A category has been added: do nothing. <p>
*
* @see org.opencms.workplace.tools.searchindex.CmsHookList#onAdded(java.lang.Object, int, java.lang.Object)
*/
protected void onAdded(Object peer, int index, Object element) {
// nop
}
/**
* @see org.opencms.workplace.tools.searchindex.CmsHookList#onAdded(java.lang.Object, java.lang.Object)
*/
protected void onAdded(Object peer, Object added) {
// nop
}
/**
* Takes a copy of the current categories contained to a backup list as this
* operation is triggered by
* <code>{@link org.opencms.workplace.CmsWidgetDialog#ACTION_SAVE}</code>.<p>
*
* @see org.opencms.workplace.tools.searchindex.CmsHookList#onClear(java.lang.Object)
*/
protected void onClear(Object peer) {
m_backupCategories = new LinkedList(this);
}
/**
*
* @see org.opencms.workplace.tools.searchindex.CmsHookList#onCleared(java.lang.Object)
*/
protected void onCleared(Object peer) {
// nop
}
/**
* Set the search page of the peer Object
* (<code>{@link org.opencms.search.CmsSearch#setSearchPage(int)}</code>)
* to zero if the internal backup list of categories (taken at clear time which
* is triggered by <code>{@link org.opencms.workplace.CmsWidgetDialog#ACTION_SAVE}</code>)
* was empty (no restriction) and now categories are contained or if the new
* backup list of categories is no subset of the current categories any
* more (more restrictive search than before). <p>
*
* @see org.opencms.workplace.tools.searchindex.CmsHookList#onGetCall(java.lang.Object, int)
*/
protected void onGetCall(Object peer, int index) {
// zero categories are all (first condition)
if ((m_backupCategories.size() == 0 && size() != 0) || !(containsAll(m_backupCategories))) {
((CmsSearchParameters)peer).setSearchPage(1);
}
}
/**
* @see org.opencms.workplace.tools.searchindex.CmsHookList#onIteratorCall(java.lang.Object)
*/
protected void onIteratorCall(Object peer) {
// nop
}
/**
* A category has been removed: set search page to start page as
* new results may / will be smaller. <p>
*
*
* @see org.opencms.workplace.tools.searchindex.CmsHookList#onRemoved(java.lang.Object, int)
*/
protected void onRemoved(Object peer, int index) {
((CmsSearchParameters)peer).setSearchPage(1);
}
}