How to handle multiple files and messages for internationalization in Spring?

Question

Some articles about Spring internationalization tell how to swap messages passing the locale and etc, but I only found use cases that contains a few messages..

• How can I organize and use internationalization files per context? (validation, view messages, default messages, business messages)

• I know that Spring uses the pattern (name of message file defined) + locale. e.g: message_zh_CN. How can I have files per context knowing about this behavior?

What I think it should be:

resources
`-- messages
    |-- validation
    |   |-- message_locale.properties
    |   `-- message_locale2.properties
    |-- business
    |   |-- message_locale.properties
    |   `-- message_locale2.properties
    `-- view
        |-- message_locale.properties
        `-- message_locale2.properties

OR:

resources
`-- messages
    |-- validation
    |   |-- validation_locale.properties
    |   `-- validation_locale2.properties
    |-- business
    |   |-- business_locale.properties
    |   `-- business_locale2.properties
    `-- view
        |-- view_locale.properties
        `-- view_locale2.properties

Answer 1

You can either define a global MessageSource for all those different message files. This approach is practical using the setBasenames method:

@Bean
public MessageSource messageSource() {
    ReloadableResourceBundleMessageSource messageSource = 
                                               new ReloadableResourceBundleMessageSource();
    messageSource.setBasenames("classpath:/messages/business/message", 
                               "classpath:/messages/validation/message",
                               "classpath:/messages/view/message");

    return messageSource;
}

This approach makes sense if your message keys are unique across all files, e.g. business-12 key only exits in business related message sources. Otherwise, it's better to define one MessageSource per context and inject them according to your context:

@Bean
public MessageSource businessMessageSource() {
    ReloadableResourceBundleMessageSource messageSource = 
                                               new ReloadableResourceBundleMessageSource();
    messageSource.setBasename("classpath:/messages/business/message");

    return messageSource;
}

@Bean
public MessageSource validationMessageSource() {
    ReloadableResourceBundleMessageSource messageSource = 
                                               new ReloadableResourceBundleMessageSource();
    messageSource.setBasename("classpath:/messages/validation/message");

    return messageSource;
}

@Bean
public MessageSource viewMessageSource() {
    ReloadableResourceBundleMessageSource messageSource = 
                                               new ReloadableResourceBundleMessageSource();
    messageSource.setBasename("classpath:/messages/view/message");

    return messageSource;
}