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List:       velocity-user
Subject:    Re: Following up on key / value loops and Map.Entry
From:       "Geir Magnusson Jr." <geirm () optonline ! net>
Date:       2001-05-25 12:50:08
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"Henning P. Schmiedehausen" wrote:
> 
> Hi,
> 
> some weeks ago, someone asked about loops over Hashtables in
> Templates:
> 
> foreach( $entry in $table )
> My $entry is $table.get($entry)
> #end
> 
> with $table being a Hashtable or a HashMap. But "$entry" loops over
> the values, not over the keys. And there is no "value -> key" lookup
> method.
> 

First, to just solve the problem, why not iterate over the keyset?

#foreach($key in $hashtable.keySet() )
  key = $key  value = $hashtable.get($key)
#end

:)

> One of the proposed ways to do this was a posting which suggested
> using the Map.Entry interface which should make the following thing
> possible:
> 
> [SNIP]

> I was wondering, whether it is possible to recognize such situations.

> [SNIP]

> I was also asking myself, whether this could be a bug in the JDK. What
> sense makes the current behaviour?
> 
>         Regards
>                 Henning
> 

No, you are right on - the problem is due to the fact that we are
'method-centric' in our introspection, and we need to address the public
interfaces on default, protected or private-scope classes.

I was working on a general solution, not just localized to the
PropertyExecutor, for this problem.  I even had it in the HEAD CVS until
I realized how wrong it was :)  and decided to put it off until after
the 1.1 release. Look for it then.

geir

-- 
Geir Magnusson Jr.                           geirm@optonline.net
System and Software Consulting
Developing for the web?  See http://jakarta.apache.org/velocity/
"still climbing up to the shoulders..."

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