Re: Table creation helper package for Velocity?
Hi,
thanks a lot for the quick responses!
I haven't actually seen anyone do this sort of thing. At least, i
don't recall anyone contributing it. This would be a good thing to
have up on our Wiki somewhere (perhaps under CommunityArticles and
ContributedCode.
Yes, the CommunityArticles and ContributedCode sections
look promising to me as well. I'll try to get something done soon.
I'm not as sure where the VelocityInteractor would fit, but i would be
curious to see/know more about what it does. In recent months, i've
been mulling over the possibility of a new project (or new package in
the core project) to provide super-easy-to-use wrappers around the
Velocity runtime that are pre-configured (or much more easily and
specifically configured) and enhanced for particular Velocity tasks
(e.g. like a VelocityEmailer). It's still just a thought at this
point, but a glance at how you're using it makes it look like the
VelocityInteractor could be a such a thing or at least a seed for such
things.
I have attached the source code for the VelocityInteractor. It's
not rocket science, just a wrapper that I found useful for handling
many different VelocityContexts and Templates. Maybe you also find
it useful. Feel free to use or modify.
Thanks,
Matthias
P.S.: I noticed that the mailing list archive seems to discard
attachments, at least I can't see the attachment from my previous
posting in the web interface. Let me know if I should resend it
directly.
/*
* VelocityException.java
*
* Created on 6. August 2007, 09:00
*
* To change this template, choose Tools | Template Manager
* and open the template in the editor.
*/
/**
*
* @author i000698
*/
public class VelocityException extends Exception {
/**
* Constructs a new codeVelocityException/code exception with
codenull/code as its
* detail message. The cause is not initialized, and may subsequently be
* initialized by a call to [EMAIL PROTECTED] #initCause}.
*/
public VelocityException() {
super();
}
/**
* Constructs a new codeVelocityException/code exception with the
specified detail message.
* The cause is not initialized, and may subsequently be initialized by a
* call to [EMAIL PROTECTED] #initCause}.
*
*
* @param message the detail message. The detail message is saved for
* later retrieval by the [EMAIL PROTECTED] #getMessage()} method.
*/
public VelocityException(String message) {
super(message);
}
/**
* Constructs a new codeVelocityException/code exception with the
specified detail message and
* cause. pNote that the detail message associated with
* codecause/code is inot/i automatically incorporated in
* this codeVelocityException/code exception's detail message.
*
*
* @param message the detail message (which is saved for later retrieval
* by the [EMAIL PROTECTED] #getMessage()} method).
* @param cause the cause (which is saved for later retrieval by the
* [EMAIL PROTECTED] #getCause()} method). (A ttnull/tt value is
* permitted, and indicates that the cause is nonexistent or
* unknown.)
*/
public VelocityException(String message, Throwable cause) {
super(message, cause);
}
/**
* Constructs a new codeVelocityException/code exception with the
specified cause and a
* detail message of tt(cause==null ? null : cause.toString())/tt
* (which typically contains the class and detail message of
* ttcause/tt). This constructor is useful for
codeVelocityException/code exceptions
* that are little more than wrappers for other throwables.
*
*
* @param cause the cause (which is saved for later retrieval by the
* [EMAIL PROTECTED] #getCause()} method). (A ttnull/tt value is
* permitted, and indicates that the cause is nonexistent or
* unknown.)
*/
public VelocityException(Throwable cause) {
super(cause);
}
}
import java.io.Writer;
import java.util.HashMap;
import java.util.Map;
import org.apache.velocity.Template;
import org.apache.velocity.VelocityContext;
import org.apache.velocity.app.Velocity;
import org.apache.velocity.exception.MethodInvocationException;
import org.apache.velocity.exception.ParseErrorException;
import org.apache.velocity.exception.ResourceNotFoundException;
import org.apache.velocity.runtime.RuntimeConstants;
/**
* A helper class to encapsulate the interaction with the Velocity template
engine
*/
public class VelocityInteractor {
private static final String ENCODING = ISO-8859-1;
private MapString,VelocityContext contexts = new
HashMapString,VelocityContext();
private MapString,Templatetemplates= new
HashMapString,Template();
private MapString,TemplatedefaultTemplates = new
HashMapString,Template();
private VelocityContext defaultContext = new VelocityContext();
private
Re: Table creation helper package for Velocity?
Nathan, Nathan Bubna wrote: I also wonder if there's some way to turn your Table/Cell classes into a TableTool of sorts that could go into the VelocityTools project. http://velocity.apache.org/tools/devel/ While I think this is an interesting tool, I don't think it's widely applicable enough to go into the VelocityTools project. Most of the tools already provided are useul in a very wide range of applications, but this one seems very narrow. I like your idea of putting it onto the Contributed Code section of the Wiki, though. Just my two cents. -chris signature.asc Description: OpenPGP digital signature
Re: Table creation helper package for Velocity?
On 8/7/07, Christopher Schultz [EMAIL PROTECTED] wrote: Nathan, Nathan Bubna wrote: I also wonder if there's some way to turn your Table/Cell classes into a TableTool of sorts that could go into the VelocityTools project. http://velocity.apache.org/tools/devel/ While I think this is an interesting tool, I don't think it's widely applicable enough to go into the VelocityTools project. Most of the tools already provided are useul in a very wide range of applications, but this one seems very narrow. Organizing data into tables is pretty common. things like DisplayTag are quite popular in the JSP world (actually displaytag is 80% of why i like to see Velocity and JSP play together better). While it would probably take a herculean effort to turn this into a match for that anytime soon, having something to simplify the process of outputting tables of data would be a small step in that direction. i'm not saying that i'm sure this would fit in VelocityTools, but i'm think it might with a little work. i'd at least like to see more of it. I like your idea of putting it onto the Contributed Code section of the Wiki, though. Just my two cents always appreciated!! -chris - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
Table creation helper package for Velocity?
Hi, in my work I quite frequently have the requirement to create somewhat complex HTML tables using Velocity. complex here refers to cells spanning multiple rows and columns which are located somewhere inside the table. That of course leads to interesting challenges in the Velocity macro to print the proper HTML tags such as tr and td in those places where they are required. Until recently, I used hierarchies of #if directives together with marker variables (#set) e. g. to decide when to print a tr for a cell that spans multiple rows. Since that became quite tedious and difficult to maintain I have searched for an easier way to manage such tables with Velocity. Since I couldn't find anything really I decided to write some helper classes myself. To give you an example of what I mean: This code snippet VelocityInteractor interactor = new VelocityInteractor(.); Table table = new Table(10, 15); table.setClipping(true); Cell cell = new Cell(test, 4, 3); table.setCell(cell, 2, 2); cell = new Cell(test22, 2, 13); table.setCell(cell, 8, 6); cell = new Cell(test33, 10, 1); table.setCell(cell, 0, 0); table.setCell(cell, 0, 5); cell = new Cell(test44, 4, 4); table.setCell(cell, 0, 11); BufferedWriter writer = new BufferedWriter(new FileWriter(test.html)); interactor.add(table.vm); interactor.put(table, table); interactor.merge(writer); writer.flush(); writer.close(); creates a table and adds some cells to it. The cells span multiple rows and columns. Table and Cell are classes that I have created. The Velocity macro table.vm used here is quite simple: html body #set ( $rowMax = $table.rowNumber - 1 ) #set ( $colMax = $table.colNumber - 1 ) table border=1 cellspacing=0 cellpadding=0 #foreach ( $row in [0..$rowMax]) tr #foreach ( $col in [0..$colMax]) #if ( $table.isVisible($row, $col) ) #if ( $table.isDefaultCell($row, $col) ) td ($row,$col) /td #else #set ( $cell = $table.getCell($row, $col) ) td rowspan=$cell.rowSpan colspan=$cell.colSpan align=center $cell.name /td #end #end #end #end /table /body /html and the example HTML output file is attached. All the cells are as expected with a very simple and clean Velicity macro structure. There is a lot more that could be said about these helper classes (for example on how cell data can be transported into the Velocity macro), but the main question for me is: is this something that is useful such that it's worth writing some short article about it for the benefit of others - or has this been solved a thousand times before (and much better) but I used the wrong keywords in Google when checking for that? I realize of course that this is something to complement Velocity and has nothing to do with enhancing Velocity itself. Nevertheless, any feedback on the usefulness of this for the general public would be appreciated. I would then invest more time in documentation and additional debugging and look for a place to make this available. Maybe there is a general place for Velocity add-ons? Thanks a lot, Matthias - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
