Re: Wait for User Input

Ack. @#$%*&! Gmail. It sent if off before I was done editing. The only
thing that actually needs changing is that the line preceding the
declaration file should read:

---------------------- declare-option-dialog.xpl ---------------------

and not the Java class. Sorry for any confusion.

Ichiro


On Thu, May 16, 2013 at 8:56 PM, Ichiro Furusato
<ichiro.furusato@gmail.com>wrote:

> Hi Ari,
>
> I've had a number of occasions to develop what are essentially
> pass-through steps, i.e., steps that do something related to the pipeline
> but don't alter the actual content flowing through. Below is a very quick
> shell of a step that displays a JOptionPane that displays a dialog upon
> encountering the step. This could obviously be improved by adding passed
> arguments, actually altering processing based upon the chosen option, etc.,
> but I leave that as an exercise to the implementer since I don't know what
> you'd plan to do with it.
>
> Hopefully it's helpful.
>
> Here's the declaration:
>
> ---------------------- OptionDialogStep.java ---------------------
>     <?xml version="1.0" encoding="UTF-8"?>
>     <p:declare-step
>         name="option-dialog"
>         type="acme:option-dialog"
>         version="1.0"
>         xmlns:acme="http://acme.com/xproc/1.0/"
>         xmlns:p="http://www.w3.org/ns/xproc">
>
>        <p:input port="source"/>
>        <p:output port="result"/>
>
>     </p:declare-step>
>
> This must be imported into an existing pipeline using:
>
>     <p:import href="declare-option-dialog.xpl"/>
>
> and then used as a step, e.g.,
>
>     <acme:option-dialog name="option-dialog-step">
>         <p:documentation>
>             This is a step used to display an option dialog.
>         </p:documentation>
>     </acme:option-dialog>
>
> And here's the Java code (which I release without license restriction):
>
> ---------------------- OptionDialogStep.java ---------------------
>
> package com.acme.transform;
>
> import net.sf.saxon.s9api.SaxonApiException;
> import net.sf.saxon.s9api.XdmNode;
>
> import com.xmlcalabash.core.XProcRuntime;
> import com.xmlcalabash.io.ReadablePipe;
> import com.xmlcalabash.io.WritablePipe;
> import com.xmlcalabash.library.DefaultStep;
> import com.xmlcalabash.runtime.XAtomicStep;
> import javax.swing.JOptionPane;
>
> /**
>  *  An XProc step that displays a dialog box.
>  *
>  * @author Ichiro Furusato
>  */
> public class OptionDialogStep extends DefaultStep
> {
>     private ReadablePipe source = null;  // the source of this step
>     private WritablePipe result = null;  // the result of this step
>
>
>     public OptionDialogStep( XProcRuntime runtime, XAtomicStep step )
>     {
>         super(runtime, step);
>     }
>
>
>     @Override
>     public final void setInput( String port, ReadablePipe pipe )
>     {
>         source = pipe;
>     }
>
>
>     @Override
>     public final void setOutput( String port, WritablePipe pipe )
>     {
>         result = pipe;
>     }
>
>
>     @Override
>     public void reset()
>     {
>         if ( source != null ) {
>             source.resetReader();
>         }
>         if ( result != null ) {
>             result.resetWriter();
>         }
>     }
>
>
>     @Override
>     public void run() throws SaxonApiException
>     {
>         try {
>             Object message = "Dialog message here.";
>             String title   = "Dialog Title";
>             int option = JOptionPane.showConfirmDialog(null,
>                     message, title,
> JOptionPane.YES_NO_CANCEL_OPTION);
>             switch ( option ) {
>                 case JOptionPane.YES_OPTION:
>                     System.out.println("option: YES_OPTION");
>                     break;
>                 case JOptionPane.NO_OPTION:
>                     System.out.println("option: NO_OPTION");
>                     break;
>                 case JOptionPane.CANCEL_OPTION:
>                     System.out.println("option: CANCEL_OPTION");
>                     break;
>                 default:
>                     System.out.println("option: default");
>                     break;
>             }
>             super.run();
>
>             // get Saxon document from pipeline
>             XdmNode doc = source.read();
>             if ( doc == null ) {
>                 throw new IllegalStateException("null document.");
>             }
>             // pass through pipeline
>             result.write(doc);
>
>         } catch ( Exception e ) {
>             throw new SaxonApiException(e.getClass().getName()
>                     + " thrown by OptionDialogStep: "
>                     + e.getLocalizedMessage(), e);
>         }
>     }
>
>
> } // end OptionDialogStep
>
>