Is it possible to read static text dynamically from property files in velocity template?

问题

greetings all i have a java ee application (spring framework) that uses vm templates that contains static texts like:

<span> hello world </span>

to be something like:

<span> <fmt:message key="hi.message" /> </span>

and i was wondering if it's possible to read that texts from a property file(en/fr) depending on the user locale like in JSP, so that i will use one template for all locales and the text is dynamic

Note: velocity is not my view technology used in the app, i am using it's templates in sending emails only.

回答1:

Spring MVC comes with (very) useful velocimacros (see Spring MVC documentation). One of them is #springMessageText.

In your hello.vm file:

<span>#springMessageText("hi.message", "Hello Default!")</span>

This macro will read the message from your message sources, depending on the current locale (using the built-in ResourceBundleMessageSource from Spring).

messages_fr_FR.properties

hi.message=Bonjour

messages_en_GB.propertie

hi.message=Hello

If no bundle is available for the current locale, the default message "Hello Default!" is used.

By default, Spring is reading messages*.properties files. But you can specify more message sources in your servlet.xml configuration (here, messages*.properties and othermessages*.properties):

<bean id="messageSource"
    class="org.springframework.context.support.ResourceBundleMessageSource">
    <property name="basenames">
      <list>
        <value>messages</value>
        <value>othermessages</value>
      </list>
    </property>
</bean>

How does SpringMVC knows about the current locale?

Well, it's all built-in SpringMVC. The ResourceBundleMessageSource reads keys according to the Locale. I think a LocaleResolver is configured by default (using the locale sent along the client request), but you can register your own localeResolver.

I encourage you to check all the available springmvc velocimacros and velocity tools (very useful!).

回答2:

Velocity Tools' ResourceTool class is a tool for accessing ResourceBundles and formatting messages therein. An answer to a previous question describes how to set up Velocity Tools

In the tools configuration file, add the following line to enable ResourceTool. You can provide a default locale, but normally the locale from HttpServletRequest.getLocale() will be used.

Toolbox configuration example:
 <tools>
   <toolbox scope="request">
     <tool class="org.apache.velocity.tools.generic.ResourceTool"
              bundles="myresources"
              locale="en_US"/>
   </toolbox>
 </tools>

If your resource bundle contains

bar=The args are {0} and {1}.

you can use the following in your template

$text.bar                 ->  The args are {0} and {1}.
$text.bar.insert(4)       ->  The args are 4 and {1}.
$text.bar.insert(4,true)  ->  The args are 4 and true.

Maybe this is best shown using a fully programmatic configuration; this way you can manually set the locale each time.

EasyFactoryConfiguration config = new EasyFactoryConfiguration();
config.toolbox("request").tool(ResourceTool.class)
    .property("bundles", "myresources")
    .property("locale", "en_US");

ToolManager manager = new ToolManager(false, false);
manager.configure(config);

Context context = manager.createContext();
context.put("name", "Jarl");

Template template = Velocity.getTemplate("mytemplate.vm");

StringWriter writer = new StringWriter();
template.merge(context, writer);
System.out.println(writer.toString());

mytemplate.vm:

$text.greeting $name

myresources_en_US.properties:

greeting=Hello

Output

Hello Jarl

回答3:

this is because of your encoding, try at first to manually change the page encoding (usually in tools).

i got a bit farther in this but not much farther..Spring automatically sets the encoding to iso-8859-1, i made it set it to utf-8, however, my hebrew strings changed to gibrish, also destroyed the chance to hand-pick the right encoding as none of em seem to decode it right.

i'd really appreciate a hand in solving this problem.

回答4:

We cannot use macros outside the web app, like in my case so a solution would be to use messageSource

model.put("messagesource", this.messagesource);
// adding this e.g. should do the trick
model.put("keyHelloCustomer", "the_key_you_use_in_your_properties_file");
model.put("noArgs", new Object[]{});
model.put("locale", yourOwnPrivateMethodToDetermineWhichLocaleToUse());

and in the vm:

${messageSource.getMessage($keyHelloCustomer, $noArgs, $locale)}

reference: http://forum.springsource.org/showthread.php?t=82018

来源：https://stackoverflow.com/questions/4322783/is-it-possible-to-read-static-text-dynamically-from-property-files-in-velocity-t

标签

Spring

spring-mvc

java-ee

velocity