How to internationalize REST Spring-MVC application? - spring

I am new with spring and I still don't know well about hierarchy and terminology of spring. I am implementing a RESTful app with spring. After searching and reading about how to internationalize spring, I tried to do it in my app. But it seems to me it is not configured properly. Because I get exception. I would like to show you the screenshot of my project structure. And I would like to ask you why my applicationContext.xml show a problem exist.
spring-servlet.xml
<!-- SPRING INTERNALIZATION CONFIGURATION -->
<bean id="messageSource" class="org.springframework.context.support.ReloadableResourceBundleMessageSource">
<property name="basename" value="classpath:messages" />
<property name="defaultEncoding" value="UTF-8"/>
</bean>
<bean id="localeResolver" class="org.springframework.web.servlet.i18n.CookieLocaleResolver">
<property name="defaultLocale" value="en"/>
</bean>
<bean id="localeChangeInterceptor" class="org.springframework.web.servlet.i18n.LocaleChangeInterceptor">
<property name="paramName" value="language" />
</bean>
<bean id="handlerMapping" class="org.springframework.web.servlet.mvc.annotation.DefaultAnnotationHandlerMapping">
<property name="interceptors">
<ref bean="localeChangeInterceptor" />
</property>
</bean>

The javadoc of ReloadableResourceBundleMessageSource.setBaseNames() says:
Set an array of basenames, each following the basic ResourceBundle convention of not specifying file extension or language codes, but in contrast to ResourceBundleMessageSource referring to a Spring resource location: e.g. "WEB-INF/messages" for "WEB-INF/messages.properties", "WEB-INF/messages_en.properties", etc.
But you've placed your message properties files under src/main/resources in the Maven project structure, so they will end up at the root of the classpath instead (which means that even if Spring looked for them in the classpath, the /resources prefix you've used in the configuration would prevent Spring to find them).
So place the properties file under WEB-INF, and use WEB-INF/messages as the basenames property.

Related

Reading JNDI name from external properties file in Spring

I am developing a Spring web application where I am using JMS as well as some datasource connection.
Now Instead of hardcoding the JNDI names of DataSource/Jms Connection Factory,I want to read them from a external properties file.
I used the following configuration::
<bean id="myProps" class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer">
<property name="locations" value="classpath*:myFile"/>
<property name="ignoreUnresolvablePlaceholders" value="true"/>
</bean>
`<jee:jndi-lookup` id="dataSource" jndi-name="${DS_JNDI}" expected-type="javax.sql.DataSource"/>
But during deployment time it is throwing an error in weblogic:::
javax.naming.NameNotFoundException: Unable to resolve '${DS_JNDI}'. Resolved ''; remaining name '${DS_JNDI}'
Is it like that I cannot put a property file entry when using <jee:jndi-lookup>???
you should remove the star after classpath, and add properties of file extension
<bean id="myProps" class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer">
<property name="locations" value="classpath:myFile.properties"/>
<property name="ignoreUnresolvablePlaceholders" value="true"/>
</bean>
<bean id="myProperties" class="org.springframework.beans.factory.config.PropertiesFactoryBean">
<property name="locations">
<list>
<value>classpath*:myFile.properties</value>
</list>
</property>
</bean>
This is the correct solution of the problem.I think from Spring5.x onwards it has stopped appending ".properties" extension.

Internationalisation with Spring

I have an existing Spring/GWT Application which i need to add internationalisation to. My understanding is that i can use Spring's "ResourceBundleMessageSource" to automatically select the appropriate messages_* file depending on the users location. I tried following this tutorial but i can't seem to get the Application to display my strings in French. As it stands, I've added 2 files messages_en_US.properties and messages_fr_FR.properties into my src/main/resources/i18n folder and added the following to the applicationContext.XML:
<bean id="messageSource"
class="org.springframework.context.support.ResourceBundleMessageSource">
<property name="basename">
<value>classpath:i18n/messages</value>
</property>
</bean>
<bean id="localeChangeInterceptor"
class="org.springframework.web.servlet.i18n.LocaleChangeInterceptor">
<property name="paramName" value="lang" />
</bean>
<bean class="org.springframework.web.servlet.mvc.support.ControllerClassNameHandlerMapping" >
<property name="interceptors">
<list>
<ref bean="localeChangeInterceptor" />
</list>
</property>
</bean>
Just wondering 1) if i need additional configuration/glue code and 2) if i can test this easily without having to set the Language/Locale to French on my Redhat Server?
It's likely that your browser sends just "fr" language tag in Accept-Header. Spring is notorious for problems with fall-back, so you may need to copy the messages_fr_FR.properties as messages_fr.properties.
I am sure there must be some ways to configure fall-back, so you want have to use messages_en.properties (try your application with other English locales...), just messages.properties should do, but I am just too lazy/tired to look for solution at the moment.
Here you need to specify below bean in spring.xml.
<bean id="messageSource" class="org.springframework.context.support.ReloadableResourceBundleMessageSource">
<property name="basename" value="classpath:messages" />
<property name="defaultEncoding" value="UTF-8" />
</bean>
<bean id="localeResolver" class="org.springframework.web.servlet.i18n.CookieLocaleResolver">
<property name="defaultLocale" value="en"/>
</bean>
<mvc:interceptors>
<bean id="localeChangeInterceptor" class="org.springframework.web.servlet.i18n.LocaleChangeInterceptor">
<property name="paramName" value="lang" />
</bean>
</mvc:interceptors>
This works perfectly fine when you pass lang=es in query string. If still any issue remain.you can check the working example Here .

Several PropertyPlaceholderConfigurers with spring

I have a strange problem with my spring bean definition. My application is a multi-module thing.
At the moment I have a project named core-lib which has a spring.xml file defining a PropertyPlaceholderConfigurer like this:
<bean id="corePropertyConfigurer" class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer">
<property name="order" value="10" />
<property name="locations">
<list>
<!-- default properties files containing ALL possible properties -->
<value>classpath:default.connection.properties</value>
<value>classpath:default.mq.properties</value>
<!-- installation specific, optional properties file containing overridden properties -->
<value>classpath:connection.properties</value>
<value>classpath:mq.properties</value>
</list>
</property>
<property name="ignoreResourceNotFound" value="true" />
</bean>
Second I have a depending project which has its own spring.xml file including the one from the core-lib project. Moreover it defines a second PropertyPlaceholderConfigurer like this:
<!-- import configuration from service layer -->
<import resource="classpath:spring.xml"/>
<bean id="commPropertyConfigurer" class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer">
<property name="order" value="20" />
<property name="locations">
<list>
<!-- properties files containing ALL possible properties -->
<value>classpath:processing.properties</value>
</list>
</property>
<property name="ignoreResourceNotFound" value="true" />
</bean>
Now I have the behavior that a bean defined in this second spring PlaceholderConfigurer can't be instantiated due to missing properties:
BeanDefinitionStoreException: Invalid bean definition with name 'commServer' defined in class path resource [comm-server.spring.xml]: Could not resolve placeholder 'comm.server.CommServer.port'
If I set a breakpoint in the PropertyPlaceholderConfigurer class it only get's triggered for the first bean instance and never for the second. Has anyone had a similar setup and can give me some advice?
Thanks,
Sebastian
There is a more comfortable way by defining a new placeholder prefix and suffix:
<bean id="propertyConfigurer"
class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer">
<property name="location">
<value>classpath:configuration.properties</value>
</property>
<property name="placeholderPrefix" value="myprefix{" />
<property name="placeholderSuffix" value="}" />
</bean>
Found here: http://javalibs.blogspot.co.at/2008/04/java-spring-framework-multiple.html
OK I resolved that myself, although I do not understand why this is working so strange.
I have defined a different prefix in the second placeholder (?{ instead of ${) and now its working. I had expected that this would work without any special prefixes...

deployment for different environments with maven and spring

I've got two properties files:
environment.properties:
- project.host.db3.database.name=oracle
application.properties:
- database.name=${project.host.db3.database.name}
The first one represents the environment variables and the second one the properties to be used in a spring project, in this configuration i try to set the environment.properties but of course it doesn't work:
<bean id="systemPropertiesLoader"
class="org.springframework.beans.factory.config.MethodInvokingFactoryBean">
<property name="targetObject" value="#{#systemProperties}" />
<property name="targetMethod" value="putAll" />
<property name="arguments">
<util:properties location="classpath:environment.properties" />
</property>
</bean>
<bean id="propertyPlaceholderConfigurer"
class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer"
depends-on="systemPropertiesLoader">
<property name="locations">
<list>
<value>classpath:application.properties</value>
</list>
</property>
<!-- bean using database.name -->
Is it doable?, and if not, how do people have agnostic properties in their projects (like database.name), and only one file (war, jar, etc.) to be deployed?
Well, it seems it's doable for beans xml defined as long as you define your properties it like this:
<bean id="propertyPlaceholderConfigurer"
class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer"
depends-on="systemPropertiesLoader">
But if you ever try to access the properties from a servlet:
this.getClass().getClassLoader().getResourceAsStream("application.properties");
chances are you get this:
bad port configuration: ${project.host.db3.database.port}
java.lang.NumberFormatException: For input string: "${project.host.db3.database.port}"
In answer to yorkw, now i can have the same war to be deployed in several environments and configure the host with -Denvironment=development, so i can deploy a properties file for development, production, etc. and simply use:
<bean id="systemPropertiesLoader"
class="org.springframework.beans.factory.config.MethodInvokingFactoryBean">
<property name="targetObject" value="#{#systemProperties}" />
<property name="targetMethod" value="putAll" />
<property name="arguments">
<util:properties location="classpath:**${environment}/**environment.properties" />
</property>
</bean>
Otherwise i should have the application.properties substituted before deployment for every environment. I'm sure there are better solutions than this.

<jee:jndi-lookup default-value and the use of classpath

I am really stuck on this one... Help! :)
I am using j2ee:jndi lookup for a property file. The following works fine:
<bean class="org.springframework.core.io.FileSystemResource">
<constructor-arg>
<jee:jndi-lookup id="myProps" jndi-name="myProps" resource-ref="true" />
</constructor-arg>
</bean>
However, I want to handle the case where the jndi lookup fails but will fall back on a default file located in WEB-INF/classes folder. If I use the default-value as below, the webapp throws an exception complaining that it cannot find the file "classpath:myprops.properties"
<bean class="org.springframework.core.io.FileSystemResource">
<constructor-arg>
<jee:jndi-lookup id="myProps" jndi-name="myProps" resource-ref="true"
default-value="classpath:myprops.properties" />
</constructor-arg>
</bean>
However, if I hard-code a specific path for default-value, then it works fine, but that is unacceptable as a final solution.
Thus, my issue is how to use "classpath:" so that it gets properly resolved?
This is the overall usage I'm employing:
<bean id="authServerProperties"
class="org.springframework.beans.factory.config.PropertiesFactoryBean">
<property name="ignoreResourceNotFound" value="true"/>
<property name="location">
<bean class="org.springframework.core.io.FileSystemResource">
<constructor-arg>
<jee:jndi-lookup id="myProps" jndi-name="myProps" resource-ref="true"
default-value="classpath:myprops.properties" />
</constructor-arg>
</bean>
</property>
.....
</bean>
Let Spring use its built-in PropertyEditor support to decide on the type of resource, rather than supplying an explicit FileSystemResource bean as this won't work with classpath resources (it needs to be configured with a path on the file system). Instead you should use something like
<bean id="authServerProperties"
class="org.springframework.beans.factory.config.PropertiesFactoryBean">
<property name="ignoreResourceNotFound" value="true"/>
<property name="location" ref="myProps" />
</bean>
<jee:jndi-lookup id="myProps" jndi-name="myProps" resource-ref="true"
default-value="classpath:myprops.properties"/>
Here we are setting the location to be a string value and allowing Spring to convert that to the appropriate resource type, so if you have
<env-entry>
<env-entry-name>myProps</env-entry-name>
<env-entry-type>java.lang.String</env-entry-type>
<env-entry-value>file:///Users/something/myProps.properties</env-entry-value>
</env-entry>
in your web.xml, it will use a UrlResource with the given file URL, otherwise it will create a ClasspathResource to look for the file myprops.properties.

Resources