mirror of
https://github.com/almet/notmyidea.git
synced 2025-04-28 19:42:37 +02:00
225 lines
No EOL
12 KiB
HTML
225 lines
No EOL
12 KiB
HTML
<!DOCTYPE html>
|
|
<html lang="en">
|
|
<head>
|
|
<title>Using JPype to bridge python and Java</title>
|
|
<meta charset="utf-8" />
|
|
<link rel="stylesheet" href="./theme/css/main.css" type="text/css" />
|
|
<link href="./feeds/all.atom.xml" type="application/atom+xml" rel="alternate" title="Alexis' log ATOM Feed" />
|
|
|
|
|
|
<!--[if IE]>
|
|
<script src="http://html5shiv.googlecode.com/svn/trunk/html5.js"></script><![endif]-->
|
|
|
|
<!--[if lte IE 7]>
|
|
<link rel="stylesheet" type="text/css" media="all" href="./css/ie.css"/>
|
|
<script src="./js/IE8.js" type="text/javascript"></script><![endif]-->
|
|
|
|
<!--[if lt IE 7]>
|
|
<link rel="stylesheet" type="text/css" media="all" href="./css/ie6.css"/><![endif]-->
|
|
|
|
</head>
|
|
|
|
<body id="index" class="home">
|
|
|
|
<a href="http://github.com/ametaireau/">
|
|
|
|
<img style="position: absolute; top: 0; right: 0; border: 0;" src="http://s3.amazonaws.com/github/ribbons/forkme_right_red_aa0000.png" alt="Fork me on GitHub" />
|
|
|
|
</a>
|
|
|
|
<header id="banner" class="body">
|
|
<h1><a href=".">Alexis' log </a></h1>
|
|
<nav><ul>
|
|
|
|
|
|
|
|
<li><a href="./pages/projects.html">projects</a></li>
|
|
|
|
|
|
|
|
<li ><a href="./category/asso.html">asso</a></li>
|
|
|
|
<li class="active"><a href="./category/dev.html">dev</a></li>
|
|
|
|
<li ><a href="./category/python.html">python</a></li>
|
|
|
|
<li ><a href="./category/system.html">system</a></li>
|
|
|
|
<li ><a href="./category/thoughts.html">thoughts</a></li>
|
|
|
|
</ul></nav>
|
|
</header><!-- /#banner -->
|
|
|
|
<section id="content" class="body">
|
|
<article>
|
|
<header> <h1 class="entry-title"><a href=""
|
|
rel="bookmark" title="Permalink to Using JPype to bridge python and Java">Using JPype to bridge python and Java</a></h1> </header>
|
|
<div class="entry-content">
|
|
<footer class="post-info">
|
|
<abbr class="published" title="2011-06-11T00:00:00">
|
|
Sat 11 June 2011
|
|
</abbr>
|
|
|
|
|
|
<address class="vcard author">
|
|
By <a class="url fn" href="./author/Alexis Métaireau.html">Alexis Métaireau</a>
|
|
</address>
|
|
|
|
<p>In <a href="./category/dev.html">dev</a>. </p>
|
|
<p>tags: <a href="./tag/python.html">python</a><a href="./tag/java.html">java</a></p>
|
|
|
|
|
|
</footer><!-- /.post-info -->
|
|
<p>Java provides some interesting libraries that have no exact equivalent in
|
|
python. In my case, the awesome boilerpipe library allows me to remove
|
|
uninteresting parts of HTML pages, like menus, footers and other "boilerplate"
|
|
contents.</p>
|
|
<p>Boilerpipe is written in Java. Two solutions then: using java from python or
|
|
reimplement boilerpipe in python. I will let you guess which one I chosen, meh.</p>
|
|
<p>JPype allows to bridge python project with java libraries. It takes another
|
|
point of view than Jython: rather than reimplementing python in Java, both
|
|
languages are interfacing at the VM level. This means you need to start a VM
|
|
from your python script, but it does the job and stay fully compatible with
|
|
Cpython and its C extensions.</p>
|
|
<div class="section" id="first-steps-with-jpype">
|
|
<h2>First steps with JPype</h2>
|
|
<p>Once JPype installed (you'll have to hack a bit some files to integrate
|
|
seamlessly with your system) you can access java classes by doing something
|
|
like that:</p>
|
|
<div class="highlight"><pre><span class="kn">import</span> <span class="nn">jpype</span>
|
|
<span class="n">jpype</span><span class="o">.</span><span class="n">startJVM</span><span class="p">(</span><span class="n">jpype</span><span class="o">.</span><span class="n">getDefaultJVMPath</span><span class="p">())</span>
|
|
|
|
<span class="c"># you can then access to the basic java functions</span>
|
|
<span class="n">jpype</span><span class="o">.</span><span class="n">java</span><span class="o">.</span><span class="n">lang</span><span class="o">.</span><span class="n">System</span><span class="o">.</span><span class="n">out</span><span class="o">.</span><span class="n">println</span><span class="p">(</span><span class="s">"hello world"</span><span class="p">)</span>
|
|
|
|
<span class="c"># and you have to shutdown the VM at the end</span>
|
|
<span class="n">jpype</span><span class="o">.</span><span class="n">shutdownJVM</span><span class="p">()</span>
|
|
</pre></div>
|
|
<p>Okay, now we have a hello world, but what we want seems somehow more complex.
|
|
We want to interact with java classes, so we will have to load them.</p>
|
|
</div>
|
|
<div class="section" id="interfacing-with-boilerpipe">
|
|
<h2>Interfacing with Boilerpipe</h2>
|
|
<p>To install boilerpipe, you just have to run an ant script:</p>
|
|
<pre class="literal-block">
|
|
$ cd boilerpipe
|
|
$ ant
|
|
</pre>
|
|
<p>Here is a simple example of how to use boilerpipe in Java, from their sources</p>
|
|
<div class="highlight"><pre><span class="kn">package</span> <span class="n">de</span><span class="o">.</span><span class="na">l3s</span><span class="o">.</span><span class="na">boilerpipe</span><span class="o">.</span><span class="na">demo</span><span class="o">;</span>
|
|
<span class="kn">import</span> <span class="nn">java.net.URL</span><span class="o">;</span>
|
|
<span class="kn">import</span> <span class="nn">de.l3s.boilerpipe.extractors.ArticleExtractor</span><span class="o">;</span>
|
|
|
|
<span class="kd">public</span> <span class="kd">class</span> <span class="nc">Oneliner</span> <span class="o">{</span>
|
|
<span class="kd">public</span> <span class="kd">static</span> <span class="kt">void</span> <span class="nf">main</span><span class="o">(</span><span class="kd">final</span> <span class="n">String</span><span class="o">[]</span> <span class="n">args</span><span class="o">)</span> <span class="kd">throws</span> <span class="n">Exception</span> <span class="o">{</span>
|
|
<span class="kd">final</span> <span class="n">URL</span> <span class="n">url</span> <span class="o">=</span> <span class="k">new</span> <span class="n">URL</span><span class="o">(</span><span class="s">"http://notmyidea.org"</span><span class="o">);</span>
|
|
<span class="n">System</span><span class="o">.</span><span class="na">out</span><span class="o">.</span><span class="na">println</span><span class="o">(</span><span class="n">ArticleExtractor</span><span class="o">.</span><span class="na">INSTANCE</span><span class="o">.</span><span class="na">getText</span><span class="o">(</span><span class="n">url</span><span class="o">));</span>
|
|
<span class="o">}</span>
|
|
<span class="o">}</span>
|
|
</pre></div>
|
|
<p>To run it:</p>
|
|
<div class="highlight"><pre><span class="nv">$ </span>javac -cp dist/boilerpipe-1.1-dev.jar:lib/nekohtml-1.9.13.jar:lib/xerces-2.9.1.jar src/demo/de/l3s/boilerpipe/demo/Oneliner.java
|
|
<span class="nv">$ </span>java -cp src/demo:dist/boilerpipe-1.1-dev.jar:lib/nekohtml-1.9.13.jar:lib/xerces-2.9.1.jar de.l3s.boilerpipe.demo.Oneliner
|
|
</pre></div>
|
|
<p>Yes, this is kind of ugly, sorry for your eyes.
|
|
Let's try something similar, but from python</p>
|
|
<div class="highlight"><pre><span class="kn">import</span> <span class="nn">jpype</span>
|
|
|
|
<span class="c"># start the JVM with the good classpaths</span>
|
|
<span class="n">classpath</span> <span class="o">=</span> <span class="s">"dist/boilerpipe-1.1-dev.jar:lib/nekohtml-1.9.13.jar:lib/xerces-2.9.1.jar"</span>
|
|
<span class="n">jpype</span><span class="o">.</span><span class="n">startJVM</span><span class="p">(</span><span class="n">jpype</span><span class="o">.</span><span class="n">getDefaultJVMPath</span><span class="p">(),</span> <span class="s">"-Djava.class.path=</span><span class="si">%s</span><span class="s">"</span> <span class="o">%</span> <span class="n">classpath</span><span class="p">)</span>
|
|
|
|
<span class="c"># get the Java classes we want to use</span>
|
|
<span class="n">DefaultExtractor</span> <span class="o">=</span> <span class="n">jpype</span><span class="o">.</span><span class="n">JPackage</span><span class="p">(</span><span class="s">"de"</span><span class="p">)</span><span class="o">.</span><span class="n">l3s</span><span class="o">.</span><span class="n">boilerpipe</span><span class="o">.</span><span class="n">extractors</span><span class="o">.</span><span class="n">DefaultExtractor</span>
|
|
|
|
<span class="c"># call them !</span>
|
|
<span class="k">print</span> <span class="n">DefaultExtractor</span><span class="o">.</span><span class="n">INSTANCE</span><span class="o">.</span><span class="n">getText</span><span class="p">(</span><span class="n">jpype</span><span class="o">.</span><span class="n">java</span><span class="o">.</span><span class="n">net</span><span class="o">.</span><span class="n">URL</span><span class="p">(</span><span class="s">"http://blog.notmyidea.org"</span><span class="p">))</span>
|
|
</pre></div>
|
|
<p>And you get what you want.</p>
|
|
<p>I must say I didn't thought it could work so easily. This will allow me to
|
|
extract text content from URLs and remove the <em>boilerplate</em> text easily
|
|
for infuse (my master thesis project), without having to write java code, nice!</p>
|
|
</div>
|
|
|
|
</div><!-- /.entry-content -->
|
|
|
|
<div class="comments">
|
|
<h2>Comments !</h2>
|
|
<div id="disqus_thread"></div>
|
|
<script type="text/javascript">
|
|
var disqus_identifier = "using-jpype-to-bridge-python-and-java.html";
|
|
(function() {
|
|
var dsq = document.createElement('script'); dsq.type = 'text/javascript'; dsq.async = true;
|
|
dsq.src = 'http://blog-notmyidea.disqus.com/embed.js';
|
|
(document.getElementsByTagName('head')[0] || document.getElementsByTagName('body')[0]).appendChild(dsq);
|
|
})();
|
|
</script>
|
|
</div>
|
|
|
|
|
|
</article>
|
|
</section>
|
|
|
|
<section id="extras" class="body">
|
|
|
|
<div class="blogroll">
|
|
<h2>blogroll</h2>
|
|
<ul>
|
|
|
|
<li><a href="http://biologeek.org">Biologeek</a></li>
|
|
|
|
<li><a href="http://filyb.info/">Filyb</a></li>
|
|
|
|
<li><a href="http://www.libert-fr.com">Libert-fr</a></li>
|
|
|
|
<li><a href="http://prendreuncafe.com/blog/">N1k0</a></li>
|
|
|
|
<li><a href="http://ziade.org/blog">Tarek Ziadé</a></li>
|
|
|
|
<li><a href="http://zubin71.wordpress.com/">Zubin Mithra</a></li>
|
|
|
|
</ul>
|
|
</div><!-- /.blogroll -->
|
|
|
|
|
|
<div class="social">
|
|
<h2>social</h2>
|
|
<ul>
|
|
<li><a href="./feeds/all.atom.xml" rel="alternate">atom feed</a></li>
|
|
|
|
|
|
|
|
<li><a href="http://twitter.com/ametaireau">twitter</a></li>
|
|
|
|
<li><a href="http://lastfm.com/user/akounet">lastfm</a></li>
|
|
|
|
<li><a href="http://github.com/ametaireau">github</a></li>
|
|
|
|
</ul>
|
|
</div><!-- /.social -->
|
|
|
|
</section><!-- /#extras -->
|
|
|
|
<footer id="contentinfo" class="body">
|
|
<address id="about" class="vcard body">
|
|
Proudly powered by <a href="http://alexis.notmyidea.org/pelican/">pelican</a>, which takes great advantages of <a href="http://python.org">python</a>.
|
|
</address><!-- /#about -->
|
|
|
|
<p>The theme is by <a href="http://coding.smashingmagazine.com/2009/08/04/designing-a-html-5-layout-from-scratch/">Smashing Magazine</a>, thanks!</p>
|
|
</footer><!-- /#contentinfo -->
|
|
|
|
|
|
|
|
|
|
<script type="text/javascript">
|
|
var disqus_shortname = 'blog-notmyidea';
|
|
(function () {
|
|
var s = document.createElement('script'); s.async = true;
|
|
s.type = 'text/javascript';
|
|
s.src = 'http://' + disqus_shortname + '.disqus.com/count.js';
|
|
(document.getElementsByTagName('HEAD')[0] || document.getElementsByTagName('BODY')[0]).appendChild(s);
|
|
}());
|
|
</script>
|
|
|
|
</body>
|
|
</html> |