Develop Reference

How can I access an central ResourceBundle in Wicket

The Internationalization of Wicket is realized with many little Properties-Files in the same folders like there html-Files.
My architekture ist one Properties-File in the webapp-Folder or an other unique Folder.
My favorite Example:
src/java/main/net/kog/WicketApplikation.java:
getResourceSettings().getResourceFinders().add(
new WebApplicationPath(getServletContext(), "resource"));
BundleStringResourceLoader bundle = new BundleStringResourceLoader("text.properties");
getResourceSettings().getStringResourceLoaders().add(bundle);
// Test
String str = bundle.loadStringResource(net.kog.resource.Text.class, "login.noscript", Locale.getDefault(), null, null);
System.out.println(str);
Markup:
<div wicket:id="login.noscript" id="js"/>
But whereever I locate the File text.properties the ResourceBundle not found, no String was returned.
tried Locations:
src/main/webapp
src/main/webapp/resource
src/main/webapp/WEB-INF/resource
src/main/webapp/WEB-INF/classes/resource
src/main/resources
src/main/resources/resource
src/main/resources/net/kog/resource

Please read http://wicket.apache.org/guide/guide/i18n.html for more information how to split or combine the resource bundles in your application.

Solution:
First, the answer of martin-g has given the right direktion. The properties-File have to be the same name like the Application-class ("WicketApplication.properties").
Second, very useful was to change the debuglevel in Wicket (src\main\resources\log4j2.xml) from LEVEL.INFO to LEVEL.DEBUG. There was a many Information about the URL (Path) which Wicket has tried to loaded.
Third, I make the way to access my properties-File shorter, because I delete IsoPropertiesFilePropertiesLoader (ISO-8859 formated Properties-Files) and XmlFilePropertiesLoader in net.kog.WicketApplication.init(). Code:
List<IPropertiesLoader> propertiesLoader =
((PropertiesFactory)getResourceSettings().getPropertiesFactory()).getPropertiesLoaders();
getResourceSettings().getPropertiesFactory().clearCache();
propertiesLoader.clear();
propertiesLoader.add(new UtfPropertiesFilePropertiesLoader("properties", "utf-8"));
The full path of my UTF-8 properties-File is src/main/webapp/net/kog/WicketApplication.properties

Localized values of ActionMessage in ValidatorForm

I have localized messages, for example:
error.message = Invalid {0}
object.foo = Foo
and some validation code within my ValidatorForm:
errors.add(ActionErrors.GLOBAL_MESSAGE, new ActionMessage("errors.message", "Foo"));
This works just fine. But I want to localize the message arguments as well using key object.foo.
I've tried:
getServlet().getInternal().getMessage("object.foo");
but this results in null. Is there some other way?

It's not so difficult, I'll try find harder next time...
org.apache.struts.validator.Resources.getMessage(request,key);

Access to MessageResources

What's the analogous of
Resources.getMessage(request,"key");
(it's in org.apache.struts.validator package)?
I need to take the right string according to the language in use and put that string in an array.
These strings have a variable part. For example:
The field %s is required
I want to take the The field and is required from the MessageResources
EDIT
I've used
ResourceBundle myResources = ResourceBundle.getBundle("MessageResources");
String msg = MessageFormat.format(myResources.getString("errors.required"),
new Object[] { title });
It works, but only with the default language

You can use a resource bundle for this in idiomatic Java. The bundles are properties files, and they are named according to their locale's.
Here is a link to ResourceBundle in the Java API documentation.
http://docs.oracle.com/javase/7/docs/api/java/util/ResourceBundle.html
Let me know if you need any more info.

Bean Validation + Resource Bundle ideas?

Here is what i want to be able to do with bean validation in my JPA entities :
Instead of #NotNull, i would like to do #NotNull(message="keyInMyResourceBundleFile")
I would like also to parameterize the resourceBundle, and i dont know the syntax for it, because it seems to me the message attribute contains only a string.
The parameter itself could be i18n-ed. For example, assuming there's a param attribute for the resourcebundle parameters, in English, #NotNull(message="missing.value", params={"credit card"}) String creditCard; It will be displayed something like this : "Missing required value for field credit card. In Indonesia, it'll be something like "Nilai harus di isi untuk Kartu Kredit. In this example, i cant hardcode the "credit card" because in Indonesia, it's "Kartu Kredit"
Displays the error message defined in the resource bundle on the log file or UI. Im not sure the way on how to do it, should i catch the ConstraintViolationException, get the message, and process the resource bundle by my own code ?
Please share your thoughts on this ?
Thank you !

Regarding 1 + 2
#NotNull(message="{keyInMyResourceBundleFile}")
Curly brackets are the indicator of a parameter substitution
Regarding 3
No idea what you are after. There is no params attribute for #NotNull. I guess you would do
#NotNull(message="{missing.credit.card}")
And of if you place it on another property you would call the key {missing.name}
Regarding 4
The ConstraintViolationException contains the set of *ConstraintViolation*s. Each ConstraintViolation contains the interpolated message as well as the message template. If you want to log it, do it ...

Do resource bundles in Java support runtime string substitution?

Can you do the following with a Java ResourceBundle?
In the properties file...
example.dynamicresource=You currently have {0} accounts.
At runtime...
int accountAcount = 3;
bundle.get("example.dynamicresource",accountCount,param2,...);
To give a result of
"You currently have 3 accounts."

Not without using the MessageFormat class, such as:
String pattern = bundle.getString("example.dynamicresource");
String message = MessageFormat.format(pattern, accountCount);

On their own, ResourceBundle does not support property placeholders. The usual idea is to take the String you get from the bundle, and stick it into a MessageFormat, and then use that to get your parameterized message.
If you're using JSP/JSTL, then you can combine <fmt:message> and <fmt:param> to do this, which uses ResourceBundle and MessageFormat under the covers.
If you happen to be using Spring, then it has the ResourceBundleMessageSource which does something similar, and can be used anywhere in your program. This MessageSource abstraction (combined with MessageSourceAccessor) is much nicer to use than ResourceBundle.

There are various ways, depending on the view technology you're using. If you're using "plain vanilla" Java (e.g. Swing), then use MessageFormat API as answered before. If you're using a webapplication framework (which is true, if I judge your question history here correctly), then the way depends on the view technology and/or MVC framework you're using. If it is for example "plain vanilla" JSP, then you can use JSTL fmt:message for this.
<fmt:message key="example.dynamicresource">
<fmt:param value="${bean.accountCount}">
</fmt:message>
If it is for example JSF, you can use h:outputFormat for this.
<h:outputFormat value="#{bundle['example.dynamicresource']}">
<f:param value="#{bean.accountCount}">
</h:outputFormat>
Best place is to just consult the documentation of the technology/framework you're using (or to tell it here so that we can give better suited and more detailed answers).

Struts have a nice util called MessageResources which does exactly what you ask for....
e.g.
MessageResources resources = getResources(request, "my_resource_bundle"); // Call your bundle exactly like ResourceBundle.getBundle() method
resources.getMessage("example.dynamicresource",accountCount,param2,...);
Limitation
It only allows maximum of 3 parameters (i.e. resource attribute, param1, ..., param3).
I suggest using MessageFormat (if you want to use more than 3 parameter values) as suggested by David Sykes.
PS the getResources method is available only in the Struts Action class.

I don't think you can make this work for Non-English properties file.
My message.properties file has the following line:
info.fomat.log.message.start=Starting to parse log message in {0} format.
And my message_fr_FR.properties file has the following line:
info.fomat.log.message.start=A partir d'analyser le message connecter {0} format.
This code works only for the English one
String.format((String) messages .getString(GlobalConstants.MESSAGE_FORMAT_START), GlobalConstants.STR_JSON));
It does NOT replace the placeholder with the value when my language / locale is French :-(
Even MessageFormat.fomat() is no good

I don't believe ResourceBundle can do that itself, but String can:
String.format(bundle.getString("example.dynamicresource"), accountCount);

Remember that when using MessageFormat.format() you need to use a double quote ('') in your resource bundle if you want to express single quote (').

MessageFormoat#format will work for the case like:
greetingTo=Have Param, saying hello {0}
You can declare two methods like this where RB is a instance of ResourceBundle:
/**This is a method that takes the param to substitute the placeholder**/
public String getString(String key, Object... params ) {
try {
return MessageFormat.format(this.RB.getString(key), params);
} catch (MissingResourceException e) {
return "[" + key + "]";
}
}
/**Without a param, this will derectly delegate to ResourceBundle#getString**/
public String getString(String key) {
try {
return this.RB.getString(key);
} catch (MissingResourceException e) {
return "[" + key + "]";
}
}