Mercurial > jdk8-mips64-public > nashorn / file revision

 #// Usage: jjs -scripting gutenberg.js

 /*

  * Copyright (c) 2014, Oracle and/or its affiliates. All rights reserved.

  * 

  * Redistribution and use in source and binary forms, with or without

  * modification, are permitted provided that the following conditions

  * are met:

  * 

  *   - Redistributions of source code must retain the above copyright

  *     notice, this list of conditions and the following disclaimer.

  * 

  *   - Redistributions in binary form must reproduce the above copyright

  *     notice, this list of conditions and the following disclaimer in the

  *     documentation and/or other materials provided with the distribution.

  * 

  *   - Neither the name of Oracle nor the names of its

  *     contributors may be used to endorse or promote products derived

  *     from this software without specific prior written permission.

  * 

  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS

  * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,

  * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR

  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT OWNER OR

  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,

  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,

  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR

  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF

  * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING

  * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS

  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

  */

 // Simple example that demonstrates reading XML Rss feed

 // to generate a HTML file from script and show it by browser

 // Java classes used

 var Characters = Java.type("javax.xml.stream.events.Characters");

 var Factory = Java.type("javax.xml.stream.XMLInputFactory");

 var File = Java.type("java.io.File");

 var FileWriter = Java.type("java.io.FileWriter");

 var PrintWriter = Java.type("java.io.PrintWriter");

 var URL = Java.type("java.net.URL");

 // read Rss feed from a URL. Returns an array

 // of objects having only title and link properties

 function readRssFeed(url) {

     var fac = Factory.newInstance();

     var reader = fac.createXMLEventReader(url.openStream());

     // get text content from next event

     function getChars() {

         var result = "";

         var e = reader.nextEvent();

         if (e instanceof Characters) {

             result = e.getData();

         }

         return result;

     }

     var items = [];

     var title, link;

     var inItem = false;

     while (reader.hasNext()) {

         var evt = reader.nextEvent();

         if (evt.isStartElement()) {

             var local = evt.name.localPart;

             if (local == "item") {

                // capture title, description now

                inItem = true;

             }

             if (inItem) {

                 switch (local) {

                     case 'title':

                         title = getChars();

                         break;

                     case 'link':

                         link = getChars();

                         break;

                 }

             }

         } else if (evt.isEndElement()) {

             var local = evt.name.localPart;

             if (local == "item") {

                 // one item done, save it in result array

                 items.push({ title: title, link: link });

                 inItem = false;

             }

         }

     }

     return items;

 }

 // generate simple HTML for an RSS feed

 function getBooksHtml() {

     var url = new URL("http://www.gutenberg.org/cache/epub/feeds/today.rss");

     var items = readRssFeed(url);

     var str = "<ul>";

     // Nashorn's string interpolation and heredoc

     // support is very handy in generating text content

     // that is filled with elements from runtime objects.

     // We insert title and link in <li> elements here.

     for each (i in items) {

         str += <<EOF

 <li>

     <a href="${i.link}">${i.title}</a>

 </li>

 EOF

     }

     str += "</ul>";

     return str;

 }

 // write the string to the given file

 function writeTo(file, str) {

     var w = new PrintWriter(new FileWriter(file));

     try {

         w.print(str);

     } finally {

         w.close();

     }

 }

 // generate books HTML

 var str = getBooksHtml();

 // write to file. __DIR__ is directory where

 // this script is stored.

 var file = new File(__DIR__ + "books.html");

 writeTo(file, str);

 // show it by desktop browser

 try {

     var Desktop = Java.type("java.awt.Desktop");

     Desktop.desktop.browse(file.toURI());

 } catch (e) {

     print(e);

 }