Source Code Cross Referenced for JavaScriptJXPathBindingBuilder.java in  » Content-Management-System » apache-lenya-2.0 » org » apache » cocoon » woody » binding » Java Source Code / Java DocumentationJava Source Code and Java Documentation

001:        /*
002:         * Licensed to the Apache Software Foundation (ASF) under one or more
003:         * contributor license agreements.  See the NOTICE file distributed with
004:         * this work for additional information regarding copyright ownership.
005:         * The ASF licenses this file to You under the Apache License, Version 2.0
006:         * (the "License"); you may not use this file except in compliance with
007:         * the License.  You may obtain a copy of the License at
008:         * 
009:         *      http://www.apache.org/licenses/LICENSE-2.0
010:         * 
011:         * Unless required by applicable law or agreed to in writing, software
012:         * distributed under the License is distributed on an "AS IS" BASIS,
013:         * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014:         * See the License for the specific language governing permissions and
015:         * limitations under the License.
016:         */
017:        package org.apache.cocoon.woody.binding;
018:
019:        import org.apache.cocoon.woody.binding.JXPathBindingManager.Assistant;
020:        import org.apache.cocoon.woody.util.DomHelper;
021:        import org.apache.cocoon.woody.util.JavaScriptHelper;
022:        import org.mozilla.javascript.Script;
023:        import org.w3c.dom.Element;
024:
025:        /**
026:         * Builds a {@link Binding} based on two JavaScript snippets, respectively for loading and saving the form.
027:         * <p>
028:         * The syntax for this binding is as follows :
029:         * <pre>
030:         *   &lt;wb:javascript id="foo" path="@foo"&gt;
031:         *     &lt;wb:load-form&gt;
032:         *       var appValue = jxpathPointer.getValue();
033:         *       var formValue = doLoadConversion(appValue);
034:         *       widget.setValue(formValue);
035:         *     &lt;/wb:load-form&gt;
036:         *     &lt;wb:save-form&gt;
037:         *       var formValue = widget.getValue();
038:         *       var appValue = doSaveConversion(formValue);
039:         *       jxpathPointer.setValue(appValue);
040:         *     &lt;/wb:save-form&gt;
041:         *   &lt;/wb:javascript&gt;
042:         * </pre>
043:         * This example is rather trivial and could be replaced by a simple &lt;wb:value&gt;, but
044:         * it shows the available variables in the script:
045:         * <ul>
046:         * <li><code>widget</code>: the widget identified by the "id" attribute,
047:         * <li><code>jxpathPointer</code>: the JXPath pointer corresponding to the "path" attribute,
048:         * <li><code>jxpathContext</code> (not shown): the JXPath context corresponding to the "path" attribute
049:         * </ul>
050:         * <b>Notes:</b><ul>
051:         * <li>The &lt;wb:save-form&gt; snippet should be ommitted if the "direction" attribute is set to "load".</li>
052:         * <li>The &lt;wb:load-form&gt; snippet should be ommitted if the "direction" attribute is set to "save".</li>
053:         * </ul>
054:         *
055:         * @author <a href="http://www.apache.org/~sylvain/">Sylvain Wallez</a>
056:         * @version CVS $Id: JavaScriptJXPathBindingBuilder.java 433543 2006-08-22 06:22:54Z crossley $
057:         */
058:        public class JavaScriptJXPathBindingBuilder extends
059:                JXPathBindingBuilderBase {
060:
061:            public JXPathBindingBase buildBinding(Element element,
062:                    Assistant assistant) throws BindingException {
063:                try {
064:                    CommonAttributes commonAtts = JXPathBindingBuilderBase
065:                            .getCommonAttributes(element);
066:
067:                    String id = DomHelper.getAttribute(element, "id");
068:                    String path = DomHelper.getAttribute(element, "path");
069:
070:                    Script loadScript = null;
071:                    if (commonAtts.loadEnabled) {
072:                        Element loadElem = DomHelper.getChildElement(element,
073:                                BindingManager.NAMESPACE, "load-form");
074:                        if (loadElem == null) {
075:                            throw new BindingException(
076:                                    "Element \"load-form\" is missing ("
077:                                            + DomHelper.getLocation(element)
078:                                            + ")");
079:                        }
080:                        loadScript = JavaScriptHelper.buildScript(loadElem);
081:                    }
082:
083:                    Script saveScript = null;
084:                    if (commonAtts.saveEnabled) {
085:                        Element saveElem = DomHelper.getChildElement(element,
086:                                BindingManager.NAMESPACE, "save-form");
087:                        if (saveElem == null) {
088:                            throw new BindingException(
089:                                    "Element \"save-form\" is missing ("
090:                                            + DomHelper.getLocation(element)
091:                                            + ")");
092:                        }
093:                        saveScript = JavaScriptHelper.buildScript(saveElem);
094:                    }
095:
096:                    return new JavaScriptJXPathBinding(commonAtts, id, path,
097:                            loadScript, saveScript);
098:
099:                } catch (Exception e) {
100:                    throw new BindingException("Cannot build binding at "
101:                            + DomHelper.getLocation(element), e);
102:                }
103:            }
104:        }