tomcat-taglibs-user mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Helios Alonso <halo...@atg.com.uy>
Subject RE: [JSTL] Indexed array variable
Date Wed, 02 Jun 2004 15:05:20 GMT
2 questions:

1) At the moment, does EL allows bracket notation for accesing arrays?
2) If the answer is yes, it works with associations? (Maps from -let's say- 
strings, to beans)

Sorry, I can't try now...

At 10:53 02/06/2004 -0400, you wrote:
>Good question!  We can represent a multi-dimensional array as a
>recursive array of arrays.  For example, given tag <c:setArray>, we
>could both allocate and assign a two-dimensional array as follows:
>
><%-- Create the first row, assign it values at index 0 and 1.
><%-- Assign the row to myArray at index 0. --%>
><c:setArray var="row" index="0" value="0"/>
><c:setArray var="row" index="1" value="1"/>
><c:setArray var="myArray" index="0" value="${row}"/>
>
><%-- Create the second row, assign it values at index 2 and 3.
><%-- Assign the row to myArray at index 0. --%>
><c:setArray var="row" index="0" value="2"/>
><c:setArray var="row" index="1" value="3"/>
><c:setArray var="myArray" index="1" value="${row}"/>
>
>${myArray} now contains [[0,1], [2,3]].
>
>We can use the JSP Expression Language to access each array element so
>that
>
><c:out value="${myArray[0][0]}"/>
><c:out value="${myArray[0][1]}"/>
><c:out value="${myArray[1][1]}"/>
><c:out value="${myArray[1][2]}"/>
>
>outputs
>
>0 1 2 3
>
>Note that each index of 'myArray' refers to a row, each of which is a
>one-dimensional array.  By induction, this model extends to
>multi-dimensional arrays where each element of an array may refer to
>another one-dimensional array whose elements may themselves each refer
>to another one-dimensional array, and so on.
>
>What do you think?
>
>Derek
>
> > -----Original Message-----
> > From: Simon Benzekri
> > Sent: June 2, 2004 10:10 AM
> > To: Tag Libraries Users List
> > Subject: RE: [JSTL] Indexed array variable
> >
> >
> > Good idea but how will multi-dimensional arrays be populated?
> >
> > Simon
> >
> > -----Original Message-----
> > From: Helios Alonso [mailto:halonso@atg.com.uy]
> > Sent: Wednesday, June 02, 2004 9:48 AM
> > To: Tag Libraries Users List
> > Subject: RE: [JSTL] Indexed array variable
> >
> > It would be great.  I think it's very appropiate (very common
> > idea even for
> > non-programmers, easy to implement).
> >
> > By example (my case):  I want to make a calendar and would
> > like to make it
> > very generical.  If I could use associations with taglibs, I'd make
> > something that gives me dates (or months, weeks, and days),
> > and another
> > bean associating days to properties.  It helps mantaining the
> > calendar code
> > independent from the "properties" code.  And properties could be
> > associations too:
> >
> > 'holiday' -> boolean
> > 'holidayname' -> name
> > 'itemscount' -> int
> >
> > and so on.
> >
> > The JSP would poduce HTML for the calendar, but guided by the
> > properties of
> > each day (holidays in red, days with items with a link, etc.)
> >
> > At 09:25 02/06/2004 -0400, you wrote:
> > >I think you're right.  Just like no JSTL tag exists to create an
> > >associative array (a bean or a map indexed by string), no JSTL tag
> > >exists that can explicitly allocate an indexed array.  <jsp:useBean>
> > >can create both associative and indexed arrays, and <c:set> can set
> > >associative array properties, but not indexed array
> > elements.  I think
> > >the only solution, then, is to create my own tag handler similar to
> > ><c:set> that can assign array elements.  Of course, this is
> > >non-standard, but will solve my problem.
> > >
> > >Will the next version of JSTL enhance <c:set> to permit the
> > assignment
> > >of array elements?
> > >
> > >Derek
> > >
> > > > -----Original Message-----
> > > > From: Bill Siggelkow [mailto:billsigg@bellsouth.net]
> > > > Sent: June 1, 2004 8:49 PM
> > > > To: 'Tag Libraries Users List'
> > > > Subject: RE: [JSTL] Indexed array variable
> > > >
> > > >
> > > > I don't think that JSTL is going to be able to "create" array
> > > > elements. I think you will need to allocate the array
> > ahead of time.
> > > > Maybe someone else can clarify this a little more.
> > > >
> > > >
> > > > Bill Siggelkow
> > > > billsigg@bellsouth.net
> > > >
> > > >
> > > > -----Original Message-----
> > > > From: Derek Mahar [mailto:DMahar@penson.ca]
> > > > Sent: Tuesday, June 01, 2004 5:10 PM
> > > > To: Tag Libraries Users List
> > > > Subject: [JSTL] Indexed array variable
> > > >
> > > > How does one create and assign elements to an indexed
> > array variable
> > > > in JSTL or the Expression Language? <c:set> seems lacking in this
> > > > respect.
> > > >
> > > > Derek
>NOTICE: This email contains privileged and confidential information and is 
>intended only for the individual to whom it is addressed. If you are not 
>the named addressee, you should not disseminate, distribute or copy this 
>e-mail. Please notify the sender immediately by e-mail if you have 
>received this transmission by mistake and delete this communication from 
>your system. E-mail transmission cannot be guaranteed to be secured or 
>error-free as information could be intercepted, corrupted, lost, 
>destroyed, arrive late or incomplete, or contain viruses.
>
>AVIS: Le présent courriel contient des renseignements de nature 
>privilégiée et confidentielle et n’est destiné qu'à la personne à qui il 
>est adressé. Si vous n’êtes pas le destinataire prévu, vous êtes par les 
>présentes avisés que toute diffusion, distribution ou reproduction de 
>cette communication est strictement interdite.  Si vous avez reçu ce 
>courriel par erreur, veuillez en aviser immédiatement l’expéditeur et le 
>supprimer de votre système. Notez que la transmission de courriel ne peut 
>en aucun cas être considéré comme inviolable ou exempt d’erreur puisque 
>les informations qu’il contient pourraient être interceptés, corrompues, 
>perdues, détruites, arrivées en retard ou incomplètes ou contenir un virus.
>
>---------------------------------------------------------------------
>To unsubscribe, e-mail: taglibs-user-unsubscribe@jakarta.apache.org
>For additional commands, e-mail: taglibs-user-help@jakarta.apache.org



---------------------------------------------------------------------
To unsubscribe, e-mail: taglibs-user-unsubscribe@jakarta.apache.org
For additional commands, e-mail: taglibs-user-help@jakarta.apache.org


Mime
View raw message