/*
* 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.forms.binding;
import org.apache.cocoon.forms.binding.JXPathBindingManager.Assistant;
import org.apache.cocoon.forms.util.DomHelper;
import org.apache.cocoon.forms.util.JavaScriptHelper;
import org.mozilla.javascript.Script;
import org.w3c.dom.Element;
/**
* Builds a {@link Binding} based on two JavaScript snippets, respectively for loading and saving the form.
* <p>
* The syntax for this binding is as follows :
* <pre>
* <fb:javascript id="foo" path="@foo">
* <fb:load-form>
* var appValue = jxpathPointer.getValue();
* var formValue = doLoadConversion(appValue);
* widget.setValue(formValue);
* </fb:load-form>
* <fb:save-form>
* var formValue = widget.getValue();
* var appValue = doSaveConversion(formValue);
* jxpathPointer.setValue(appValue);
* </fb:save-form>
* </fb:javascript>
* </pre>
* This example is rather trivial and could be replaced by a simple <fb:value>, but
* it shows the available variables in the script:
* <ul>
* <li><code>widget</code>: the widget identified by the "id" attribute,
* <li><code>jxpathPointer</code>: the JXPath pointer corresponding to the "path" attribute,
* <li><code>jxpathContext</code> (not shown): the JXPath context corresponding to the "path" attribute
* </ul>
* <b>Notes:</b><ul>
* <li>The <fb:save-form> snippet should be ommitted if the "direction" attribute is set to "load".</li>
* <li>The <fb:load-form> snippet should be ommitted if the "direction" attribute is set to "save".</li>
* </ul>
*
* @author <a href="http://www.apache.org/~sylvain/">Sylvain Wallez</a>
* @version CVS $Id: JavaScriptJXPathBindingBuilder.java,v 1.2 2004/03/24 01:32:45 joerg Exp $
*/
public class JavaScriptJXPathBindingBuilder extends JXPathBindingBuilderBase {
public JXPathBindingBase buildBinding(Element element, Assistant assistant) throws BindingException {
try {
CommonAttributes commonAtts = JXPathBindingBuilderBase.getCommonAttributes(element);
String id = DomHelper.getAttribute(element, "id");
String path = DomHelper.getAttribute(element, "path");
Script loadScript = null;
if (commonAtts.loadEnabled) {
Element loadElem = DomHelper.getChildElement(element, BindingManager.NAMESPACE, "load-form");
if (loadElem == null) {
throw new BindingException("Element \"load-form\" is missing (" +
DomHelper.getLocation(element) + ")");
}
loadScript = JavaScriptHelper.buildScript(loadElem);
}
Script saveScript = null;
if (commonAtts.saveEnabled) {
Element saveElem = DomHelper.getChildElement(element, BindingManager.NAMESPACE, "save-form");
if (saveElem == null) {
throw new BindingException("Element \"save-form\" is missing (" +
DomHelper.getLocation(element) + ")");
}
saveScript = JavaScriptHelper.buildScript(saveElem);
}
return new JavaScriptJXPathBinding(commonAtts, id, path, loadScript, saveScript);
} catch(Exception e) {
throw new BindingException("Cannot build binding at " + DomHelper.getLocation(element), e);
}
}
}