Jython - using Pygments in Java project

Question

I'm trying to use Pygments in Java project by including Jython.jar. In my Java project I have src/main/python source directory where I placed pygments files into pygments folder so they end up on the classpath. Now I created highlighter.py file in the src/main/python with the following content:

import sys
sys.path.append('WEB-INF/classes')
from pygments import highlight
from pygments.lexers import get_lexer_by_name
from pygments.formatters import HtmlFormatter

class Highlighter:
    def colorize(code, lexername):
        lexer = get_lexer_by_name(lexername, stripall=True)
        formatter = HtmlFormatter(linenos=True, cssclass="source")
        return highlight(code, lexer, formatter)

Then I defined Java interface Highlighter.java

public interface Highlighter {
    String colorize(String rawText, String lexer);
}

And lastly I created factory class that uses PythonInterpreter to expose highlighter.py as a Jython object as described here

Now, when I run this line of code

Highlighter hl = (Highlighter) jf.getJythonObject(Highlighter.class.getName(), 
       "WEB-INF/classes/highlighter.py");

I get PyException as follows

Traceback (most recent call last):
File "WEB-INF/classes/highlighter.py", line 3, in 
  from pygments import highlight
LookupError: no codec search functions registered: can't find encoding

This occurs if I use Jython v. 2.5.0. In 2.1 I had to copy Jython/Lib directory under src/main/python but then I end up missing IOString module

Or maybe there's a better way to achieve what I'm trying to achieve? I'm curious if anyone was able to use Pygments in Java project. I would greatly appreciate any suggestions

Now when you mentioned it I have added sys.path.append('WEB-INF/classes') to highlighter.py. Testing — Bostone
– Bostone, Commented Nov 29, 2010 at 22:43

Bostone · Accepted Answer · 2010-11-30 19:12:34Z

1

All right. I figured it out. Made few beginner errors but if you are wondering how to make Pygments work in your Java project here's full tutorial link

Highlights:

Using bare jython.jar is insufficient.
Adding Jython/Lib to your classpath doesn't work. I ended up unjarring jython.jar and adding Lib directory + all pygments files to the resulting structure and then jarring it up again
Factory example form the link above is convoluted. Much better way is to use Jython book chapter 10
For examples of changed highlighter.py, Highlighter.java and HighlighterFactory.java see the tutorial

answered Nov 30, 2010 at 19:12

Bostone

37.2k40 gold badges172 silver badges230 bronze badges

Sign up to request clarification or add additional context in comments.

2 Comments

Bostone Over a year ago

And it performs like hell. Abandoned, but the tutorial is good for general setup of Jython in Java webapp

Darren Greaves Over a year ago

Hi, how was performance just for code snippets of 10-20 lines max?

Collectives™ on Stack Overflow

Jython - using Pygments in Java project

1 Answer 1

2 Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

2 Comments

Your Answer

Sign up or log in

Post as a guest

Related