[ channel icon ]

Channels

The channels are present in the Transmorpher transformations as names in the in and out attributes of all other elements (and the test attribute of the repreat element).

<process name="myproc" in="c1" out="c2 c3"> <dispatch type="broadcast" id="dp" in="c1" out="c2 c3"/> </process>

Content, encodings and types

So far, the channels always carry SAX 2.0 (Simple API for XML) events in which characters are encoded in UTF-8. There is no explicit notion of DTD for these SAX event streams. So validation cannot take place on them.

 [ stdin icon ]  [ stdout icon ]

Standard input and output

Standard input and output are denoted by the channel names _stdin_ and _stdout_. The standard input can only be used in standlone external interface (or main), the standard output can be used both in the standalone and the servlet external interfaces.

<main> <apply-process name="myproc" id="mp" in="_stdin_" out="_stdout_ c"/> <serialize type="" id="ser" in="c"> <with-param name="file">myfile.xml</with-param> </serialize> </main>

 [ null icon ]

The _null_ channel

The null channel is used when the output of a particular call is not useful and has to be ignored. This special channel is denoted by the _null_ and can be used everywhere an output channel is used.

<process name="myproc2" in="c1" out="c2"> <apply-process name="myproc" id="mp" in="c1" out="c2 _null_"/> </process>

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Feel free to comment to transmorpher-dev@fluxmedia.fr, Last modified: Tue May 29 14:16:53 CEST 2001
$Id: channels.html,v 1.2 2001/10/10 07:29:23 jerome Exp $