Rails - May 2009 - Looping through java hashmap from ruby through rjb

Greetings.

I am trying to list all keys in a java.util.HashMap field.

The Java code to do this looks like:
#
Collection c = hMap.values();
#

#
//obtain an Iterator for Collection
#
Iterator itr = c.iterator();
#

#
//iterate through HashMap values iterator
#
while(itr.hasNext())
  System.out.println(itr.next());


So, I took a stab at the ruby version:

# I have a java hashmap called fields that was created using iText
thusly

reader = pdfreader.new( "pdf_file.pdf" )
@form = reader.getAcroFields()
fields = @form.getFields()  # this is a hashmap of all fields on form
fields._classname  # entere in irc displays: java.util.HashMap

# So, following the java code above

c = fields.values()
itr = c.iterator()
while itr.hasNext()
 p itr.next()
end

Instead of getting the field names, I get
#<#<Class:0x2d47d74>:0x2c15208>
#<#<Class:0x2d47d74>:0x2c151a4>
#<#<Class:0x2d47d74>:0x2c150b4>

(there are three keys in the hash)

Any ideas?

Thanks,
Dan
-- 
Posted via http://www.ruby-forum.com/.

On May 25, 9:28 pm, Dan Sadaka
<rails-mailing-l...-ARtvInVfO7ksV2N9l4h3zg@public.gmane.org>
wrote:
> Greetings.
>
> I am trying to list all keys in a java.util.HashMap field.
>
> Instead of getting the field names, I get
> #<#<Class:0x2d47d74>:0x2c15208>
> #<#<Class:0x2d47d74>:0x2c151a4>
> #<#<Class:0x2d47d74>:0x2c150b4>
>
> (there are three keys in the hash)
>
Well p (or puts etc) end up calling to_s on objects, and you''re
obviously getting Object''s default to_s. Does rjb have some method to
convert java strings into ruby strings ?

Fred
> Any ideas?
>
> Thanks,
> Dan
> --
> Posted viahttp://www.ruby-forum.com/.

Frederick Cheung wrote:
> On May 25, 9:28�pm, Dan Sadaka
<rails-mailing-l...-ARtvInVfO7ksV2N9l4h3zg@public.gmane.org>
> wrote:
>>
> Well p (or puts etc) end up calling to_s on objects, and you''re
> obviously getting Object''s default to_s. Does rjb have some method
to
> convert java strings into ruby strings ?
> 
> Fred
Fred,

Good question.

I did some research and found enough to try using itr.next().to_string 
and guess what.  It worked!

I had tried ruby''s .to_s and naively thought that rjb was translating
it
to the java equivalent because I wasn''t getting an error.

Thanks-a-bunch for the guidance,
Dan
-- 
Posted via http://www.ruby-forum.com/.