org.sakaiproject.cheftool.PagedResourceAction Maven / Gradle / Ivy
/**********************************************************************************
* $URL$
* $Id$
***********************************************************************************
*
* Copyright (c) 2004, 2005, 2006, 2008 The Sakai Foundation
*
* Licensed under the Educational Community 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.opensource.org/licenses/ECL-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.sakaiproject.cheftool;
import java.util.List;
import java.util.Vector;
import lombok.extern.slf4j.Slf4j;
import org.apache.commons.lang3.StringUtils;
import org.sakaiproject.cheftool.api.Menu;
import org.sakaiproject.cheftool.api.MenuItem;
import org.sakaiproject.cheftool.menu.MenuDivider;
import org.sakaiproject.cheftool.menu.MenuEntry;
import org.sakaiproject.cheftool.menu.MenuField;
import org.sakaiproject.entity.api.Entity;
import org.sakaiproject.event.api.SessionState;
import org.sakaiproject.util.ResourceLoader;
/**
*
* PagedResourceAction is a base class that handles paged display of lists of Resourecs.
*
*/
@Slf4j
public abstract class PagedResourceAction extends VelocityPortletPaneledAction
{
private static final long serialVersionUID = 1L;
private static ResourceLoader rb = new ResourceLoader("velocity-tool");
/** The default number of messages per page. */
protected static final int DEFAULT_PAGE_SIZE = 10;
/** portlet configuration parameter names. */
protected static final String PARAM_PAGESIZE = "pagesize";
/** state attribute names. */
protected static final String STATE_VIEW_ID = "view-id";
protected static final String STATE_TOP_PAGE_MESSAGE = "msg-top";
protected static final String STATE_PAGESIZE = "page-size";
protected static final String STATE_NUM_MESSAGES = "num-messages";
protected static final String STATE_NEXT_PAGE_EXISTS = "msg-next-page";
protected static final String STATE_PREV_PAGE_EXISTS = "msg-prev-page";
protected static final String STATE_GO_NEXT_PAGE = "msg-go-next-page";
protected static final String STATE_GO_PREV_PAGE = "msg-go-prev-page";
protected static final String STATE_GO_NEXT = "msg-go-next";
protected static final String STATE_GO_PREV = "msg-go-prev";
protected static final String STATE_NEXT_EXISTS = "msg-next";
protected static final String STATE_PREV_EXISTS = "msg-prev";
protected static final String STATE_GO_FIRST_PAGE = "msg-go-first-page";
protected static final String STATE_GO_LAST_PAGE = "msg-go-last-page";
protected static final String STATE_SEARCH = "search";
protected static final String STATE_MANUAL_REFRESH = "manual";
/** Form fields. */
protected static final String FORM_SEARCH = "search";
/**
* Implement this to return alist of all the resources that there are to page. Sort them as appropriate, and apply search criteria.
*/
protected abstract List readAllResources(SessionState state);
/**
* Populate the state object, if needed, concerning paging
*/
protected void initState(SessionState state, VelocityPortlet portlet, JetspeedRunData rundata)
{
super.initState(state, portlet, rundata);
if (state.getAttribute(STATE_PAGESIZE) == null)
{
state.setAttribute(STATE_PAGESIZE, new Integer(DEFAULT_PAGE_SIZE));
PortletConfig config = portlet.getPortletConfig();
try
{
Integer size = new Integer(config.getInitParameter(PARAM_PAGESIZE));
if (size.intValue() <= 0)
{
size = new Integer(DEFAULT_PAGE_SIZE);
log.debug("size parameter invalid: {}", config.getInitParameter(PARAM_PAGESIZE));
}
state.setAttribute(STATE_PAGESIZE, size);
}
catch (Exception any)
{
log.debug("size parameter invalid: {}", any.toString());
state.setAttribute(STATE_PAGESIZE, new Integer(DEFAULT_PAGE_SIZE));
}
}
} // initState
/**
* Add the menus for a view mode for paging.
*/
protected void addViewPagingMenus(Menu bar, SessionState state)
{
bar.add(new MenuEntry(rb.getString("viepag.prev"), (state.getAttribute(STATE_PREV_EXISTS) != null), "doView_prev"));
bar.add(new MenuEntry(rb.getString("viepag.next"), (state.getAttribute(STATE_NEXT_EXISTS) != null), "doView_next"));
} // addViewPagingMenus
/**
* Add the menus for a list mode for paging.
*/
protected void addListPagingMenus(Menu bar, SessionState state)
{
bar.add(new MenuEntry("First Page", (state.getAttribute(STATE_PREV_PAGE_EXISTS) != null), "doList_first"));
bar.add(new MenuEntry("Previous Page", (state.getAttribute(STATE_PREV_PAGE_EXISTS) != null), "doList_prev"));
bar.add(new MenuEntry("Next Page", (state.getAttribute(STATE_NEXT_PAGE_EXISTS) != null), "doList_next"));
bar.add(new MenuEntry("Last Page", (state.getAttribute(STATE_NEXT_PAGE_EXISTS) != null), "doList_last"));
} // addListPagingMenus
/**
* Add the menus for search.
*/
protected void addSearchMenus(Menu bar, SessionState state)
{
bar.add(new MenuDivider());
bar.add(new MenuField(FORM_SEARCH, "toolbar", "doSearch", (String) state.getAttribute(STATE_SEARCH)));
bar.add(new MenuEntry(rb.getString("sea.sea"), null, true, MenuItem.CHECKED_NA, "doSearch", "toolbar"));
if (state.getAttribute(STATE_SEARCH) != null)
{
bar.add(new MenuEntry(rb.getString("sea.cleasea"), "doSearch_clear"));
}
} // addSearchMenus
/**
* Prepare the current page of messages to display.
*
* @return List of MailArchiveMessage to display on this page.
*/
protected List prepPage(SessionState state)
{
List rv = new Vector();
// access the page size
int pageSize = ((Integer) state.getAttribute(STATE_PAGESIZE)).intValue();
// cleanup prior prep
state.removeAttribute(STATE_NUM_MESSAGES);
// are we going next or prev, first or last page?
boolean goNextPage = state.getAttribute(STATE_GO_NEXT_PAGE) != null;
boolean goPrevPage = state.getAttribute(STATE_GO_PREV_PAGE) != null;
boolean goFirstPage = state.getAttribute(STATE_GO_FIRST_PAGE) != null;
boolean goLastPage = state.getAttribute(STATE_GO_LAST_PAGE) != null;
state.removeAttribute(STATE_GO_NEXT_PAGE);
state.removeAttribute(STATE_GO_PREV_PAGE);
state.removeAttribute(STATE_GO_FIRST_PAGE);
state.removeAttribute(STATE_GO_LAST_PAGE);
// are we going next or prev message?
boolean goNext = state.getAttribute(STATE_GO_NEXT) != null;
boolean goPrev = state.getAttribute(STATE_GO_PREV) != null;
state.removeAttribute(STATE_GO_NEXT);
state.removeAttribute(STATE_GO_PREV);
// read all channel messages
List allMessages = readAllResources(state);
if (allMessages == null)
{
return rv;
}
// if we have no prev page and do have a top message, then we will stay "pined" to the top
boolean pinToTop = ((state.getAttribute(STATE_TOP_PAGE_MESSAGE) != null)
&& (state.getAttribute(STATE_PREV_PAGE_EXISTS) == null) && !goNextPage && !goPrevPage && !goNext && !goPrev
&& !goFirstPage && !goLastPage);
// if we have no next page and do have a top message, then we will stay "pined" to the bottom
boolean pinToBottom = ((state.getAttribute(STATE_TOP_PAGE_MESSAGE) != null)
&& (state.getAttribute(STATE_NEXT_PAGE_EXISTS) == null) && !goNextPage && !goPrevPage && !goNext && !goPrev
&& !goFirstPage && !goLastPage);
// how many messages, total
int numMessages = allMessages.size();
if (numMessages == 0)
{
return rv;
}
// save the number of messges
state.setAttribute(STATE_NUM_MESSAGES, new Integer(numMessages));
// find the position of the message that is the top first on the page
int posStart = 0;
String messageIdAtTheTopOfThePage = (String) state.getAttribute(STATE_TOP_PAGE_MESSAGE);
if (messageIdAtTheTopOfThePage != null)
{
// find the next page
posStart = findResourceInList(allMessages, messageIdAtTheTopOfThePage);
// if missing, start at the top
if (posStart == -1)
{
posStart = 0;
}
}
// if going to the next page, adjust
if (goNextPage)
{
posStart += pageSize;
}
// if going to the prev page, adjust
else if (goPrevPage)
{
posStart -= pageSize;
if (posStart < 0) posStart = 0;
}
// if going to the first page, adjust
else if (goFirstPage)
{
posStart = 0;
}
// if going to the last page, adjust
else if (goLastPage)
{
posStart = numMessages - pageSize;
if (posStart < 0) posStart = 0;
}
// pinning
if (pinToTop)
{
posStart = 0;
}
else if (pinToBottom)
{
posStart = numMessages - pageSize;
if (posStart < 0) posStart = 0;
}
// get the last page fully displayed
if (posStart + pageSize > numMessages)
{
posStart = numMessages - pageSize;
if (posStart < 0) posStart = 0;
}
// compute the end to a page size, adjusted for the number of messages available
int posEnd = posStart + (pageSize - 1);
if (posEnd >= numMessages) posEnd = numMessages - 1;
int numMessagesOnThisPage = (posEnd - posStart) + 1;
// select the messages on this page
for (int i = posStart; i <= posEnd; i++)
{
rv.add(allMessages.get(i));
}
// save which message is at the top of the page
Entity messageAtTheTopOfThePage = (Entity) allMessages.get(posStart);
state.setAttribute(STATE_TOP_PAGE_MESSAGE, messageAtTheTopOfThePage.getId());
// which message starts the next page (if any)
int next = posStart + pageSize;
if (next < numMessages)
{
state.setAttribute(STATE_NEXT_PAGE_EXISTS, "");
}
else
{
state.removeAttribute(STATE_NEXT_PAGE_EXISTS);
}
// which message ends the prior page (if any)
int prev = posStart - 1;
if (prev >= 0)
{
state.setAttribute(STATE_PREV_PAGE_EXISTS, "");
}
else
{
state.removeAttribute(STATE_PREV_PAGE_EXISTS);
}
if (state.getAttribute(STATE_VIEW_ID) != null)
{
int viewPos = findResourceInList(allMessages, (String) state.getAttribute(STATE_VIEW_ID));
// are we moving to the next message
if (goNext)
{
// advance
viewPos++;
if (viewPos >= numMessages) viewPos = numMessages - 1;
}
// are we moving to the prev message
if (goPrev)
{
// retreat
viewPos--;
if (viewPos < 0) viewPos = 0;
}
// update the view message
state.setAttribute(STATE_VIEW_ID, ((Entity) allMessages.get(viewPos)).getId());
// if the view message is no longer on the current page, adjust the page
// Note: next time through this will get processed
if (viewPos < posStart)
{
state.setAttribute(STATE_GO_PREV_PAGE, "");
}
else if (viewPos > posEnd)
{
state.setAttribute(STATE_GO_NEXT_PAGE, "");
}
if (viewPos > 0)
{
state.setAttribute(STATE_PREV_EXISTS, "");
}
else
{
state.removeAttribute(STATE_PREV_EXISTS);
}
if (viewPos < numMessages - 1)
{
state.setAttribute(STATE_NEXT_EXISTS, "");
}
else
{
state.removeAttribute(STATE_NEXT_EXISTS);
}
}
return rv;
} // prepPage
/**
* Handle a next-message (view) request.
*/
public void doView_next(RunData runData, Context context)
{
// access the portlet element id to find our state
String peid = ((JetspeedRunData) runData).getJs_peid();
SessionState state = ((JetspeedRunData) runData).getPortletSessionState(peid);
// set the flag to go to the next message on the next view
state.setAttribute(STATE_GO_NEXT, "");
} // doView_next
/**
* Handle a first-message page (list) request.
*/
public void doList_first(RunData runData, Context context)
{
// access the portlet element id to find our state
String peid = ((JetspeedRunData) runData).getJs_peid();
SessionState state = ((JetspeedRunData) runData).getPortletSessionState(peid);
// set the flag to go to the next message on the next view
state.setAttribute(STATE_GO_FIRST_PAGE, "");
} // doList_first
/**
* Handle a last-message page (list) request.
*/
public void doList_last(RunData runData, Context context)
{
// access the portlet element id to find our state
String peid = ((JetspeedRunData) runData).getJs_peid();
SessionState state = ((JetspeedRunData) runData).getPortletSessionState(peid);
// set the flag to go to the next message on the next view
state.setAttribute(STATE_GO_LAST_PAGE, "");
} // doList_last
/**
* Handle a next-page (list) request.
*/
public void doList_next(RunData runData, Context context)
{
// access the portlet element id to find our state
String peid = ((JetspeedRunData) runData).getJs_peid();
SessionState state = ((JetspeedRunData) runData).getPortletSessionState(peid);
// set the flag to go to the next page on the next list
state.setAttribute(STATE_GO_NEXT_PAGE, "");
// %%% ?? doList(runData, context);
} // doList_next
/**
* Handle a prev-message (view) request.
*/
public void doView_prev(RunData runData, Context context)
{
// access the portlet element id to find our state
String peid = ((JetspeedRunData) runData).getJs_peid();
SessionState state = ((JetspeedRunData) runData).getPortletSessionState(peid);
// set the flag to go to the prev message on the next view
state.setAttribute(STATE_GO_PREV, "");
} // doView_prev
/**
* Handle a prev-page (list) request.
*/
public void doList_prev(RunData runData, Context context)
{
// access the portlet element id to find our state
String peid = ((JetspeedRunData) runData).getJs_peid();
SessionState state = ((JetspeedRunData) runData).getPortletSessionState(peid);
// set the flag to go to the prev page on the next list
state.setAttribute(STATE_GO_PREV_PAGE, "");
} // doList_prev
/**
* Handle a Search request.
*/
public void doSearch(RunData runData, Context context)
{
// access the portlet element id to find our state
String peid = ((JetspeedRunData) runData).getJs_peid();
SessionState state = ((JetspeedRunData) runData).getPortletSessionState(peid);
// read the search form field into the state object
String search = StringUtils.trimToNull(runData.getParameters().getString(FORM_SEARCH));
// set the flag to go to the prev page on the next list
if (search == null)
{
state.removeAttribute(STATE_SEARCH);
}
else
{
state.setAttribute(STATE_SEARCH, search);
}
// start paging again from the top of the list
resetPaging(state);
} // doSearch
/**
* Handle a Search Clear request.
*/
public void doSearch_clear(RunData runData, Context context)
{
// access the portlet element id to find our state
String peid = ((JetspeedRunData) runData).getJs_peid();
SessionState state = ((JetspeedRunData) runData).getPortletSessionState(peid);
// clear the search
state.removeAttribute(STATE_SEARCH);
// start paging again from the top of the list
resetPaging(state);
} // doSearch_clear
/**
* Reset to the first page
*/
protected void resetPaging(SessionState state)
{
// we are changing the sort, so start from the first page again
state.removeAttribute(STATE_TOP_PAGE_MESSAGE);
} // resetPaging
/**
* Find the resource with this id in the list.
*
* @param messages
* The list of messages.
* @param id
* The message id.
* @return The index position in the list of the message with this id, or -1 if not found.
*/
protected int findResourceInList(List resources, String id)
{
for (int i = 0; i < resources.size(); i++)
{
// if this is the one, return this index
if (((Entity) (resources.get(i))).getId().equals(id)) return i;
}
// not found
return -1;
} // findResourceInList
} // PagedResourceAction
© 2015 - 2024 Weber Informatics LLC | Privacy Policy