/*
* Copyright 1999-2004 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 org.apache.cocoon.woody.formmodel;
import java.util.HashMap;
import java.util.Iterator;
import java.util.Locale;
import java.util.Map;
import java.util.StringTokenizer;
import org.apache.cocoon.woody.Constants;
import org.apache.cocoon.woody.FormContext;
import org.apache.cocoon.woody.event.FormHandler;
import org.apache.cocoon.woody.event.ProcessingPhase;
import org.apache.cocoon.woody.event.ProcessingPhaseEvent;
import org.apache.cocoon.woody.event.ProcessingPhaseListener;
import org.apache.cocoon.woody.event.WidgetEvent;
import org.apache.cocoon.woody.event.WidgetEventMulticaster;
import org.apache.cocoon.xml.AttributesImpl;
import org.apache.commons.collections.list.CursorableLinkedList;
import org.xml.sax.ContentHandler;
import org.xml.sax.SAXException;
/**
* A widget that serves as a container for other widgets, the top-level widget in
* a form description file.
*
* @author Bruno Dumon
* @author <a href="http://www.apache.org/~sylvain/">Sylvain Wallez</a>
* @version CVS $Id: Form.java,v 1.20 2004/03/09 13:53:55 reinhard Exp $
*/
public class Form extends AbstractContainerWidget {
private Boolean endProcessing;
private Locale locale = Locale.getDefault();
private CursorableLinkedList events;
// private FormDefinition definition;
private FormHandler formHandler;
private Widget submitWidget;
private ProcessingPhase phase = ProcessingPhase.LOAD_MODEL;
private boolean isValid = false;
private ProcessingPhaseListener listener;
private Map attributes;
public Form(FormDefinition definition) {
super(definition);
setLocation(definition.getLocation());
}
/**
* Events produced by child widgets should not be fired immediately, but queued in order to ensure
* an overall consistency of the widget tree before being handled.
*
* @param event the event to queue
*/
public void addWidgetEvent(WidgetEvent event) {
if (this.events == null) {
this.events = new CursorableLinkedList();
}
// FIXME: limit the number of events to detect recursive event loops ?
this.events.add(event);
}
/**
* Fire the widget events that have been queued. Note that event handling can fire new
* events.
*/
private void fireWidgetEvents() {
if (this.events != null) {
CursorableLinkedList.Cursor cursor = this.events.cursor();
while(cursor.hasNext()) {
WidgetEvent event = (WidgetEvent)cursor.next();
event.getSourceWidget().broadcastEvent(event);
if (formHandler != null)
formHandler.handleEvent(event);
}
cursor.close();
this.events.clear();
}
}
/**
* Get the locale to be used to process this form.
*
* @return the form's locale.
*/
public Locale getLocale() {
return this.locale;
}
/**
* Get the widget that triggered the current processing. Note that it can be any widget, and
* not necessarily an action or a submit.
*
* @return the widget that submitted this form.
*/
public Widget getSubmitWidget() {
return this.submitWidget;
}
/**
* Set the widget that triggered the current form processing.
*
* @param widget the widget
*/
public void setSubmitWidget(Widget widget) {
if (this.submitWidget != null && this.submitWidget != widget) {
throw new IllegalStateException("SubmitWidget can only be set once.");
}
if (!(widget instanceof Action)) {
endProcessing(true);
}
this.submitWidget = widget;
}
public void setFormHandler(FormHandler formHandler) {
this.formHandler = formHandler;
}
// TODO: going through the form for load and save ensures state consistency. To we add this or
// keep the binding strictly separate ?
// public void load(Object data, Binding binding) {
// if (this.phase != ProcessingPhase.LOAD_MODEL) {
// throw new IllegalStateException("Cannot load form in phase " + this.phase);
// }
// binding.loadFormFromModel(this, data);
// }
//
// public void save(Object data, Binding binding) throws BindingException {
// if (this.phase != ProcessingPhase.VALIDATE) {
// throw new IllegalStateException("Cannot save model in phase " + this.phase);
// }
//
// if (!isValid()) {
// throw new IllegalStateException("Cannot save an invalid form.");
// }
// this.phase = ProcessingPhase.SAVE_MODEL;
// binding.saveFormToModel(this, data);
// }
public void addProcessingPhaseListener(ProcessingPhaseListener listener) {
this.listener = WidgetEventMulticaster.add(this.listener, listener);
}
public void removeProcessingPhaseListener(ProcessingPhaseListener listener) {
this.listener = WidgetEventMulticaster.remove(this.listener, listener);
}
/**
* Processes a form submit. If the form is finished, i.e. the form should not be redisplayed to the user,
* then this method returns true, otherwise it returns false. To know if the form was sucessfully
* validated, use the {@link #isValid()} method.
* <p>
* Form processing consists in multiple steps:
* <ul>
* <li>all widgets read their value from the request (i.e.
* {@link #readFromRequest(FormContext)} is called recursively on
* the whole widget tree)
* <li>if there is an action event, call the FormHandler
* <li>perform validation.
* </ul>
* This processing can be interrupted by the widgets (or their event listeners) by calling
* {@link #endProcessing(boolean)}.
*/
public boolean process(FormContext formContext) {
// Fire the binding phase events
fireWidgetEvents();
// setup processing
this.submitWidget = null;
this.locale = formContext.getLocale();
this.endProcessing = null;
this.isValid = false;
// Notify the end of the current phase
if (this.listener != null) {
this.listener.phaseEnded(new ProcessingPhaseEvent(this, this.phase));
}
this.phase = ProcessingPhase.READ_FROM_REQUEST;
// Find the submit widget, if not an action
this.submitWidget = null;
String submitId = formContext.getRequest().getParameter("woody_submit_id");
if (submitId != null && submitId.length() > 0) {
StringTokenizer stok = new StringTokenizer(submitId, ".");
Widget submit = this;
while (stok.hasMoreTokens()) {
submit = submit.getWidget(stok.nextToken());
if (submit == null) {
throw new IllegalArgumentException("Invalid submit id (no such widget): " + submitId);
}
}
setSubmitWidget(submit);
}
doReadFromRequest(formContext);
fireWidgetEvents();
// Notify the end of the current phase
if (this.listener != null) {
this.listener.phaseEnded(new ProcessingPhaseEvent(this, this.phase));
}
if (this.endProcessing != null) {
return this.endProcessing.booleanValue();
}
// Validate the form
this.phase = ProcessingPhase.VALIDATE;
this.isValid = doValidate(formContext);
if (this.endProcessing != null) {
return this.endProcessing.booleanValue();
}
// Notify the end of the current phase
if (this.listener != null) {
this.listener.phaseEnded(new ProcessingPhaseEvent(this, this.phase));
}
if (this.endProcessing != null) {
// De-validate the form if one of the listeners asked to end the processing
// This allows for additional application-level validation.
this.isValid = false;
return this.endProcessing.booleanValue();
}
return this.isValid;
}
/**
* End the current form processing after the current phase.
*
* @param redisplayForm indicates if the form should be redisplayed to the user.
*/
public void endProcessing(boolean redisplayForm) {
this.endProcessing = new Boolean(!redisplayForm);
}
/**
* Was form validation successful ?
*
* @return <code>true</code> if the form was successfully validated.
*/
public boolean isValid() {
return this.isValid;
}
public void readFromRequest(FormContext formContext) {
throw new UnsupportedOperationException("Please use Form.process()");
}
private void doReadFromRequest(FormContext formContext) {
// let all individual widgets read their value from the request object
super.readFromRequest(formContext);
}
public boolean validate(FormContext formContext) {
throw new UnsupportedOperationException("Please use Form.process()");
}
public boolean doValidate(FormContext formContext) {
return super.validate(formContext);
}
public Object getAttribute(String name) {
return this.attributes == null ? null : this.attributes.get(name);
}
public void setAttribute(String name, Object value) {
if (this.attributes == null) {
this.attributes = new HashMap();
}
this.attributes.put(name, value);
}
public void removeAttribute(String name) {
if (this.attributes != null) {
this.attributes.remove(name);
}
}
private static final String FORM_EL = "form";
private static final String CHILDREN_EL = "children";
public void generateSaxFragment(ContentHandler contentHandler, Locale locale) throws SAXException {
AttributesImpl formAttrs = new AttributesImpl();
formAttrs.addCDATAAttribute("id", definition.getId());
contentHandler.startElement(Constants.WI_NS, FORM_EL, Constants.WI_PREFIX_COLON + FORM_EL, Constants.EMPTY_ATTRS);
definition.generateLabel(contentHandler);
contentHandler.startElement(Constants.WI_NS, CHILDREN_EL, Constants.WI_PREFIX_COLON + CHILDREN_EL, Constants.EMPTY_ATTRS);
Iterator widgetIt = widgets.iterator();
while (widgetIt.hasNext()) {
Widget widget = (Widget)widgetIt.next();
widget.generateSaxFragment(contentHandler, locale);
}
contentHandler.endElement(Constants.WI_NS, CHILDREN_EL, Constants.WI_PREFIX_COLON + CHILDREN_EL);
contentHandler.endElement(Constants.WI_NS, FORM_EL, Constants.WI_PREFIX_COLON + FORM_EL);
}
public void generateLabel(ContentHandler contentHandler) throws SAXException {
definition.generateLabel(contentHandler);
}
}