I think that you are in the right way, and i will continue using your approach which consists of creating multiple property files, one for each user, except that we will not use a any "huge amount of variables
in the managed bean".
So, the first step consists on managing multiple resource properties using a single resource bundle prefix ( the <var></var>
in <resource-bundle>
), in the second step we will see how to switch between those files, and in the last step we will read from property file using JSTL.
Managing multiple property files:
We start by defining our ResourceBundle in the faces-config
file:
<application>
<resource-bundle>
<base-name>UserMessages</base-name>
<var>msgs</var>
</resource-bundle>
</application>
UserMessages
is a ResourceBundle
where we will implement the logic that allow us to switch between our property files (assuming that yourpackage.user-inputs is the fully qualified name of your user-inputs.properties):
import java.util.Enumeration;
import java.util.MissingResourceException;
import java.util.ResourceBundle;
import javax.faces.context.FacesContext;
public class UserMessages extends ResourceBundle {
public UserMessages() {
// we are loading user-inputs.properties as the default properties file
setParent(getBundle("yourpackage.user-inputs", FacesContext.getCurrentInstance()
.getViewRoot().getLocale()));
}
@Override
protected Object handleGetObject(String key) {
// we could just return parent.getObject(key) but we want to respect JSF recommandations
try {
return parent.getObject(key);
} catch (MissingResourceException e) {
return "???" + key + "???";
}
}
@Override
public Enumeration<String> getKeys() {
return parent.getKeys();
}
// this is the method that will allow us to switch between our .properties
public void setResourceBundle(String basename) {
setParent(getBundle(basename, FacesContext.getCurrentInstance()
.getViewRoot().getLocale()));
}
}
Switching between property files:
In order to switch from a property file to another we will need to use the method setResourceBundle(String basename)
that we just declared in our class above, So in the managed bean where you are declaring your business logic and where you are intending to switch files depending on the user's role, you need to inject the bundle, like:
//don't forget adding getters and setters or you end with NullPointerException
@ManagedProperty("#{msgs}")
private UserMessages userMesssages;
Then, to switch to another file (admin-inputs.properties
), just use it like this:
//yourpackage.admin-inputs is the fully qualified name
userMesssages.setResourceBundle("yourpackage.admin-inputs");
NB: You can inject the bundle in that way (above) only in request scoped beans, to use it in broader scopes please see: Read i18n variables from properties file in a Bean
Now, as we can switch easily from the user-inputs
to the admin-inputs
, the last step is the easiest one.
Parsing the property file:
The bad news, is that when using this approach you will need to add rendered=""
and required=""
attribute to every input you are willing to manage (but don't forget that the good ones was that you will not need to manage variables in managed beans ;) ).
First, you need to add JSTL namespaces declaration on the top of your xhtml file:
xmlns:fn="http://java.sun.com/jsp/jstl/functions"
you can find more about JSTL functions in the javadocs, regarding the function substringAfter
:
Returns a subset of a string following a specific substring.
Example:
P.O. Box: ${fn:substringAfter(zip, "-")}
The function substringBefore
:
Returns a subset of a string before a specific substring.
Example:
Zip (without P.O. Box): ${fn:substringBefore(zip, "-")}
Second, as the first part of your String
represents the required
attribute:
//Returns the substring of msgs['searchBooks.authorName'] before the first occurrence of the separator ':'
required="${fn:substringBefore(msgs['searchBooks.authorName'], ':')}"
and the second part:
//Returns the substring of msgs['searchBooks.authorName'] after the first occurrence of the separator ':'.
rendered="${fn:substringAfter(msgs['searchBooks.authorName'], ':')}"
See also: