Looks good, thanks for sharing.
bob
Garth Dahlstrom wrote:
Hi Bob,
In the end, I ended up with a much more brutal low-tech approach that
involves updating the velocity model directly, it does one extra pass to
try to resolve embedded symbols. Here is the code...
...
protected String applyMapValuesToTemplate(String template,
Map<String,Object> mapValues) {
final String DELIMITER_PREFIX = "${";
final String DELIMITER_SUFFIX = "}";
for (String key : mapValues.keySet()) {
String matchKey = DELIMITER_PREFIX + key + DELIMITER_SUFFIX;
if (template.contains(matchKey)) {
template = template.replace(matchKey, (String)
mapValues.get(key));
}
}
return template;
}
....
// various calls to addModel including my Strings with embedded variable
....
for (String key : ((Map<String,Object>) getModel()).keySet()) {
String value = getModel().get(key).toString();
if (value.contains("${") &&
value.contains("}") &&
value.indexOf("${") <
value.indexOf("}")) {
value = applyMapValuesToTemplate(value, getModel());
getModel().put(key, value);
}
}
Cheers,
-G
__
--- == __/ t.O ==--
http://stacktrace.org/
On Tue, Jul 21, 2009 at 6:12 PM, Bob Schellink <[email protected]
<mailto:[email protected]>> wrote:
Hi Garth,
I've been wondering about this today. The most obvious solution is
probably to use Java's MessageFormat and replace the property
variables before adding them to the model. Off course MessageFormat
doesn't support named parameters, only numeric ones. So you have to use:
Intro=Hello {0}, welcome to the app
Alternatively you might want to look at Velocity Renderable[1]
interface. Its new in 1.6.
Normally Velocity will invoke the toString() method of the variable
it finds in the template. However if the variable implements
Renderable, Velocity will invoke a callback method which allows you
to manipulate the output as needed.
I haven't used this Velocity feature yet but it seems quite powerful.
Let us know what solution you end up using.
kind regards
bob
[1]:http://velocity.apache.org/engine/devel/apidocs/org/apache/velocity/runtime/Renderable.html
Garth Dahlstrom wrote:
Hi
I'm wondering if there is a recommended approach to replacing
variables that occur within other variables.
I have text which I add to the model that comes from a
properties file that looks like:
Intro=Hello ${Name}, welcome to the application
Name=John
I could break up intro into chunks in my template, but that will
make things slightly more difficult to maintain, particularily
when I send it for translation.
So, is there a way to get model-variable subsitution to run a
second time or a way for me to change the to-be-rendered output
to acomplish something like this?
Thanks,
-G
