aoqi@0: #// Usage: jjs -scripting jsadapter_dom.js
aoqi@0: 
aoqi@0: /*
aoqi@0:  * Copyright (c) 2014, Oracle and/or its affiliates. All rights reserved.
aoqi@0:  * 
aoqi@0:  * Redistribution and use in source and binary forms, with or without
aoqi@0:  * modification, are permitted provided that the following conditions
aoqi@0:  * are met:
aoqi@0:  * 
aoqi@0:  *   - Redistributions of source code must retain the above copyright
aoqi@0:  *     notice, this list of conditions and the following disclaimer.
aoqi@0:  * 
aoqi@0:  *   - Redistributions in binary form must reproduce the above copyright
aoqi@0:  *     notice, this list of conditions and the following disclaimer in the
aoqi@0:  *     documentation and/or other materials provided with the distribution.
aoqi@0:  * 
aoqi@0:  *   - Neither the name of Oracle nor the names of its
aoqi@0:  *     contributors may be used to endorse or promote products derived
aoqi@0:  *     from this software without specific prior written permission.
aoqi@0:  * 
aoqi@0:  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
aoqi@0:  * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
aoqi@0:  * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
aoqi@0:  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT OWNER OR
aoqi@0:  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
aoqi@0:  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
aoqi@0:  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
aoqi@0:  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
aoqi@0:  * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
aoqi@0:  * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
aoqi@0:  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
aoqi@0:  */
aoqi@0: 
aoqi@0: // Simple example that demonstrates reading XML Rss feed
aoqi@0: // to generate a HTML file from script and show it by browser
aoqi@0: // Uses XML DOM parser and DOM element wrapped by script 
aoqi@0: // "proxy" (JSAdapter constructor)
aoqi@0: 
aoqi@0: // Java classes used
aoqi@0: var DocBuilderFac = Java.type("javax.xml.parsers.DocumentBuilderFactory");
aoqi@0: var Node = Java.type("org.w3c.dom.Node");
aoqi@0: var File = Java.type("java.io.File");
aoqi@0: var FileWriter = Java.type("java.io.FileWriter");
aoqi@0: var PrintWriter = Java.type("java.io.PrintWriter");
aoqi@0: 
aoqi@0: // constants from Node class
aoqi@0: var ELEMENT_NODE = Node.ELEMENT_NODE;
aoqi@0: var TEXT_NODE = Node.TEXT_NODE;
aoqi@0: 
aoqi@0: // parse XML from uri and return Document
aoqi@0: function parseXML(uri) {
aoqi@0:     var docBuilder = DocBuilderFac.newInstance().newDocumentBuilder();
aoqi@0:     return docBuilder["parse(java.lang.String)"](uri);
aoqi@0: }
aoqi@0: 
aoqi@0: // get child Elements of given name of the parent element given
aoqi@0: function getChildElements(elem, name) {
aoqi@0:     var nodeList = elem.childNodes;
aoqi@0:     var childElems = [];
aoqi@0:     var len = nodeList.length;
aoqi@0:     for (var i = 0; i < len; i++) {
aoqi@0:         var node = nodeList.item(i);
aoqi@0:         if (node.nodeType == ELEMENT_NODE &&
aoqi@0:             node.tagName == name) {
aoqi@0:             childElems.push(wrapElement(node));
aoqi@0:         }
aoqi@0:     }
aoqi@0: 
aoqi@0:     return childElems;
aoqi@0: }
aoqi@0: 
aoqi@0: // get concatenated child text content of an Element
aoqi@0: function getElemText(elem) {
aoqi@0:     var nodeList = elem.childNodes;
aoqi@0:     var len = nodeList.length;
aoqi@0:     var text = '';
aoqi@0:     for (var i = 0; i < len; i++) {
aoqi@0:         var node = nodeList.item(i);
aoqi@0:         if (node.nodeType == TEXT_NODE) {
aoqi@0:             text += node.nodeValue;
aoqi@0:         } 
aoqi@0:     }
aoqi@0: 
aoqi@0:     return text;
aoqi@0: }
aoqi@0: 
aoqi@0: // Wrap DOM Element object as a convenient script object
aoqi@0: // using JSAdapter. JSAdapter is like java.lang.reflect.Proxy
aoqi@0: // in that it allows property access, method calls be trapped
aoqi@0: // by 'magic' methods like __get__, __call__.
aoqi@0: function wrapElement(elem) {
aoqi@0:     if (! elem) {
aoqi@0:         return elem;
aoqi@0:     }
aoqi@0:     return new JSAdapter() {
aoqi@0:         // getter to expose child elements and attributes by name
aoqi@0:         __get__: function(name) {
aoqi@0:             if (typeof name == 'string') {
aoqi@0:                 if (name.startsWith('@')) {
aoqi@0:                     var attr = elem.getAttributeNode(name.substring(1));
aoqi@0:                     return !attr? undefined : attr.value;
aoqi@0:                 }
aoqi@0: 
aoqi@0:                 var arr = getChildElements(elem, name);
aoqi@0:                 if (arr.length == 1) {
aoqi@0:                     // single child element, expose as single element
aoqi@0:                     return arr[0];
aoqi@0:                 } else {
aoqi@0:                     // multiple children of given name, expose as array
aoqi@0:                     return arr;
aoqi@0:                 }
aoqi@0:             }
aoqi@0:             return undefined;
aoqi@0:         },
aoqi@0: 
aoqi@0:         __call__: function(name) {
aoqi@0:             // toString override to get text content of this Element
aoqi@0:             if (name == 'toString' || name == 'valueOf') {
aoqi@0:                 return getElemText(elem);
aoqi@0:             }
aoqi@0:             return undefined;
aoqi@0:         }
aoqi@0:     }
aoqi@0: }
aoqi@0: 
aoqi@0: // generate HTML using here-doc and string interpolation
aoqi@0: function getBooksHtml() {
aoqi@0:     var doc = parseXML("http://www.gutenberg.org/cache/epub/feeds/today.rss");
aoqi@0:     // wrap document root Element as script convenient object
aoqi@0:     var rss = wrapElement(doc.documentElement);
aoqi@0:     print("rss file version " + rss['@version']);
aoqi@0: 
aoqi@0:     var str = <<HEAD
aoqi@0: 
aoqi@0: <html>
aoqi@0: <title>${rss.channel.title}</title>
aoqi@0: <body>
aoqi@0: <h1>${rss.channel.description}</h1>
aoqi@0: <p>
aoqi@0: Published on ${rss.channel.pubDate}
aoqi@0: </p>
aoqi@0: 
aoqi@0: HEAD
aoqi@0: 
aoqi@0:     var items = rss.channel.item;
aoqi@0:     for each (var i in items) {
aoqi@0:         str += <<LIST
aoqi@0: 
aoqi@0: <dl>
aoqi@0: <dt><a href="${i.link}">${i.title}</a></dt>
aoqi@0: <dd>${i.description}</dd>
aoqi@0: </dl>
aoqi@0: 
aoqi@0: LIST
aoqi@0:     }
aoqi@0:     str += <<END
aoqi@0: 
aoqi@0: </body>
aoqi@0: </html>
aoqi@0: 
aoqi@0: END
aoqi@0:     return str;
aoqi@0: }
aoqi@0: 
aoqi@0: // write the string to the given file
aoqi@0: function writeTo(file, str) {
aoqi@0:     var w = new PrintWriter(new FileWriter(file));
aoqi@0:     try {
aoqi@0:         w.print(str);
aoqi@0:     } finally {
aoqi@0:         w.close();
aoqi@0:     }
aoqi@0: }
aoqi@0: 
aoqi@0: // generate books HTML
aoqi@0: var str = getBooksHtml();
aoqi@0: 
aoqi@0: // write to file. __DIR__ is directory where
aoqi@0: // this script is stored.
aoqi@0: var file = new File(__DIR__ + "books.html");
aoqi@0: writeTo(file, str);
aoqi@0: 
aoqi@0: // show it by desktop browser
aoqi@0: try {
aoqi@0:     var Desktop = Java.type("java.awt.Desktop");
aoqi@0:     Desktop.desktop.browse(file.toURI());
aoqi@0: } catch (e) {
aoqi@0:     print(e);
aoqi@0: }