Re: Bookmarking, History and JSF

[Matthias Wessendorf]

On 1/27/06, Gary VanMatre <[EMAIL PROTECTED]> wrote:

Hi Gary,

> The basic idea creates a convention in the url for invoking the method.
> contextroot/dynamic/remoting$business/cityAndStateForZip.faces?zip=80124

Right it's all about naming conventions :-)

I looked a Business.java's cityAndStateForZip() method.
I don't like the parameter lookup by ExternalContext inside of a backing bean
That is equal to let your backing bean construktor handle that
parameter stuff...

I played during my train travel with somesthing similar.
A given url:

host/app/bookmark/test.faces?foo=HALLO&bar=moin

> A phase listener intercepts "dynamic" folder as the special identifier.
> Next comes the managed bean name and then the method.

right. my phase listener intercepts "bookmark". I strip "/bookmark"
from viewId, so I set it to "/test.jsp" (in this case)

I also have (like Shale's view controller) the convention that "test"
is the name of my backing bean bean

(yes, something like

host/app/bookmark/folder/test.faces?foo=HALLO&bar=moin

will look for a "viewController named folder$test)

Now the phase listener has the convention, that "foo" and "bar" are
the bean properties
and populates the bean with the given values.

Of course, this is a first shot. May be it is to restrictive? However,
let's see :-)

PS: code is attached... because I am away from my *real* box, (had to
use a usb stick to upload the file :-))

For Rendering the bookmarkable URL, I liked Adam's (or John's ;))
suggestion with the optional interface for the NavigationHandler

-Matthias

<code>
/*
 * Copyright 2006 The Apache Software Foundation.
 *
 * 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 net.wessendorf.faces.bookmark;

import java.util.Iterator;
import java.util.Map;
import java.util.Set;

import javax.faces.application.ViewHandler;
import javax.faces.context.FacesContext;
import javax.faces.el.ValueBinding;
import javax.faces.event.PhaseEvent;
import javax.faces.event.PhaseId;
import javax.faces.event.PhaseListener;

import org.apache.commons.lang.StringUtils;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;

/**
 *
 * @author matzew
 *
 */
public class BookmarkPhaseListener implements PhaseListener {

    private static final Log log =
LogFactory.getLog(BookmarkPhaseListener.class);
        
        public static String BOOKMARK = "/bookmark";

        private static final long serialVersionUID = 1L;

        public void afterPhase(PhaseEvent event) {
                FacesContext facesContext = event.getFacesContext();
                if(facesContext.getViewRoot().getViewId().startsWith(BOOKMARK))
                        invokeApplication(facesContext);
        }

        public void invokeApplication(FacesContext facesContext) {
                String oldViewId = facesContext.getViewRoot().getViewId();
                if(log.isTraceEnabled())
                        log.trace("Incomming view id: " + oldViewId);
                String newViewId = oldViewId.substring(BOOKMARK.length());
                facesContext.getViewRoot().setViewId(newViewId);
                if(log.isTraceEnabled())
                        log.trace("new generated view id: " + newViewId);
                
                Map parameters = 
facesContext.getExternalContext().getRequestParameterMap();
                Set keys = parameters.keySet();
                ValueBinding vb = null;
                String beanName = extractViewControllerName(newViewId);
                if(!parameters.isEmpty()){
                
                        for(Iterator it = keys.iterator(); it.hasNext();){
                                String key = it.next().toString();
                                if(log.isTraceEnabled())
                                        log.trace("Looking for vb:     "   + 
"#{" + beanName + "." + key + "}");
                                vb = 
facesContext.getApplication().createValueBinding("#{" +
beanName + "." + key + "}");
                                vb.setValue(facesContext, parameters.get(key));
                        }
                }
        }

        private String extractViewControllerName(String newViewId) {
                String extract = newViewId.substring(1);
                extract = 
extract.substring(0,extract.indexOf(ViewHandler.DEFAULT_SUFFIX));
                if(StringUtils.contains(extract, "/")){
                        extract = StringUtils.replace(extract, "/", "$");
                }
                return extract;
        }

        public void beforePhase(PhaseEvent event) {
        }

        public PhaseId getPhaseId() {
                
                return PhaseId.RESTORE_VIEW;
        }

}

</code>