Otis Gospodnetic wrote:
Step one is to identify the exact jar where this class lives. Are you sure
it's in mail.jar? Maybe it's in activate.jar?
$ jar tvf mail.jar | grep ParseException
385 Wed Oct 17 11:05:30 EST 2007 javax/mail/internet/ParseException.class
It's javamail 1.4.1. If I put mail.jar into my application's lib directory,
where all jars are put on the classpath it finds the class. However, then it
fails on another class from the BouncyCastle jars, also part of the plugin, so
it's some Nutch issue.
In the debugger, it shows the plugin descriptor's classloader having the 4
libraries in the loader.ucp.path ArrayList.
ExtensionClass.getExtensionInstance() does the following
Class extensionClazz = loader.loadClass(getClazz());
// lazy loading of Plugin in case there is no instance of the plugin
// already.
this.pluginRepository.getPluginInstance(getDescriptor());
Object object = extensionClazz.newInstance();
and it is the call to newInstance() which gives the CNF exception. The final
entry in the stack is
Launcher$AppClassLoader(ClassLoader).loadClassInternal(String), where the arg is
javax.mail.internet.ParseException.
I've not managed to figure out what part of the object creation the Nutch
classload takes part in, but it seems it doesn't have a lot to do with the
classloading for the plugins.
Antony
Otis
--
Sematext -- http://sematext.com/ -- Lucene - Solr - Nutch
----- Original Message ----
From: Antony Bowesman <[email protected]>
To: [email protected]
Sent: Friday, January 23, 2009 2:49:48 AM
Subject: Adding new plugin and classloading issues
I'm using the 0.9 plugin framework and am trying to add a new plugin and am
having classloading issues.
I want to use Javamail's mail.jar and BouncyCastle jars. My plugin
implemnentation catches javax.mail.internet.ParseException and when it tries to
create the new instance of my Parser, it gives
java.lang.NoClassDefFoundError: javax/mail/internet/ParseException
at java.lang.Class.getDeclaredConstructors0(Native Method)
at java.lang.Class.privateGetDeclaredConstructors(Class.java:2389)
at java.lang.Class.getConstructor0(Class.java:2699)
at java.lang.Class.newInstance0(Class.java:326)
at java.lang.Class.newInstance(Class.java:308)
at
org.apache.nutch.plugin.Extension.getExtensionInstance(Extension.java:160)
at
org.apache.nutch.parse.ParserFactory.getParsers(ParserFactory.java:130)
My plugin.xml has
I have tried it with the export for all libraries, also by having a lib-javamail
plugin, which does an export for mail.jar and with my plugin having the
but it just doesn't work. It seems identical to the standard PDF parsing or the
POI based parsers, so I'm at a loss...
It's a stand alone app, no Tomcat or anything else.
Any ideas?
Antony
