# Error "cannot load Java class"

**URL:** <https://www.ruby-forum.com/t/error-cannot-load-java-class/166277>\
**Category:** Ruby\
**Created:** [April 23, 2009, 12:22pm UTC](https://www.ruby-forum.com/t/error-cannot-load-java-class/166277 "2009-04-23T12:22:03Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![amabdelsalam](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/a/958977/32.png) [@amabdelsalam](https://www.ruby-forum.com/u/amabdelsalam)\
**Post date:** [April 23, 2009, 12:22pm UTC](https://www.ruby-forum.com/t/error-cannot-load-java-class/166277/1 "2009-04-23T12:22:03Z")

</div>

I’ve created two java classes that I’m trying to call from ruby file. I  
put the java classes with the ruby file in the same directory, and tried  
to run.

I accessed java classes from the ruby file using full class path like:  
Java::com.ch.Cells

but I got the following error:  
org.jruby.exceptions.RaiseException: cannot load Java class  
com.ch.Cells  
at  
com.sun.script.jruby.JRubyScriptEngine.evalNode(JRubyScriptEngine.java:456)  
at  
com.sun.script.jruby.JRubyScriptEngine.eval(JRubyScriptEngine.java:186)  
at javax.script.AbstractScriptEngine.eval(Unknown Source)

Caused by: org.jruby.exceptions.RaiseException: cannot load Java class  
com.ch.Cells  
at (unknown).(unknown)(/builtin/java/ast.rb:49)  
at  
(unknown).get\_proxy\_or\_package\_under\_package(/builtin/javasupport/java.rb:51)  
at #Class:01x965654.method\_missing(:1)  
at (unknown).(unknown)(:1)

Any help !!!

---

<div class="post-metadata">

**Author:** ![amabdelsalam](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/a/958977/32.png) [@amabdelsalam](https://www.ruby-forum.com/u/amabdelsalam)\
**Post date:** [April 23, 2009, 6:17pm UTC](https://www.ruby-forum.com/t/error-cannot-load-java-class/166277/2 "2009-04-23T18:17:06Z")

</div>

On Apr 23, 2009, at 5:22 AM, Ahmed A. wrote:

> org.jruby.exceptions.RaiseException: cannot load Java class  
> Caused by: org.jruby.exceptions.RaiseException: cannot load Java class  
> com.ch.Cells  
> at (unknown).(unknown)(/builtin/java/ast.rb:49)  
> at  
> (unknown).get\_proxy\_or\_package\_under\_package(/builtin/javasupport/  
> java.rb:51)  
> at #Class:01x965654.method\_missing(:1)  
> at (unknown).(unknown)(:1)

You need to show us the code too. Show the Java and show the ruby.

cr

---

<div class="post-metadata">

**Author:** ![amabdelsalam](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/a/958977/32.png) [@amabdelsalam](https://www.ruby-forum.com/u/amabdelsalam)\
**Post date:** [April 23, 2009, 6:51pm UTC](https://www.ruby-forum.com/t/error-cannot-load-java-class/166277/3 "2009-04-23T18:51:39Z")

</div>

Chuck R. wrote:

> On Apr 23, 2009, at 5:22 AM, Ahmed A. wrote:
> 
> > org.jruby.exceptions.RaiseException: cannot load Java class  
> > Caused by: org.jruby.exceptions.RaiseException: cannot load Java class  
> > com.ch.Cells  
> > at (unknown).(unknown)(/builtin/java/ast.rb:49)  
> > at  
> > (unknown).get\_proxy\_or\_package\_under\_package(/builtin/javasupport/  
> > java.rb:51)  
> > at #Class:01x965654.method\_missing(:1)  
> > at (unknown).(unknown)(:1)
> 
> You need to show us the code too. Show the Java and show the ruby.
> 
> cr

Here is the ruby code:  
class Cells \< Java::cz.cesnet.meta.jruby.Cells  
def initialize  
@cells = {‘a1’ =\> ‘Hello a1’};  
end  
end

here is the java code:  
ScriptEngineManager m = new ScriptEngineManager();

```
 // Override due to classpath troubles with OSGi ?
 m.registerEngineName("jruby",
     new com.sun.script.jruby.JRubyScriptEngineFactory());

 //get jruby engine
   ScriptEngine jruby = m.getEngineByName("jruby");
   //process a ruby file
   jruby.eval(new BufferedReader(new FileReader("... path to ruby 

```

file")));