UTF-8 encoding of application.properties attributes in Spring-Boot

Question

In my application.properties I add some custom attributes.

custom.mail.property.subject-message=This is a ä ö ü ß problem

In t

Answer 1

I've faced with the same problem. In Spring Boot there are 2 PropertySourceLoader which are used to load properties in application:

• PropertiesPropertySourceLoader - supports UTF-8 only when load from XML
• YamlPropertySourceLoader - supports UTF-8, but you have to change configuration format to use it

They're listed in the file https://github.com/spring-projects/spring-boot/blob/master/spring-boot/src/main/resources/META-INF/spring.factories

So we decided to write our own implementation of PropertySourceLoader which would be able to load properties from UTF-8 file correctly. The idea is from answer @BalusC - How to use UTF-8 in resource properties with ResourceBundle

Our PropertySourceLoader implementation:

public class UnicodePropertiesPropertySourceLoader implements PropertySourceLoader {

@Override
public String[] getFileExtensions() {
    return new String[]{"properties"};
}

@Override
public PropertySource load(String name, Resource resource, String profile) throws IOException {
    if (profile == null) {
        Properties properties = new Properties();
        PropertyResourceBundle bundle = new PropertyResourceBundle(new InputStreamReader(resource.getInputStream(), "UTF-8"));
        Enumeration keys = bundle.getKeys();
        while (keys.hasMoreElements()) {
            String key = keys.nextElement();
            properties.setProperty(key, bundle.getString(key));
        }
        if (!properties.isEmpty()) {
            return new PropertiesPropertySource(name, properties);
        }
    }
    return null;
}

}

Then we created file resources/META-INF/spring.factories with content:

# Custom PropertySource Loaders
org.springframework.boot.env.PropertySourceLoader=\
your.own.package.UnicodePropertiesPropertySourceLoader

Now we have 3 PropertySourceLoader in our application in following order:

• UnicodePropertiesPropertySourceLoader
• PropertiesPropertySourceLoader
• YamlPropertySourceLoader

NOTES!

1. I'm not sure that it is proper usage of PropertyResourceBundle
2. I'm not sure that order of PropertySourceLoaders in Spring Boot will be the same if you make a dedicated library to reuse it in other projects.

In our project this solution works fine.

UPDATE!

It's better to implement load method of UnicodePropertiesPropertySourceLoader without PropertyResourceBundle:

@Override
public PropertySource load(String name, Resource resource, String profile) throws IOException {
    if (profile == null) {
        Properties properties = new Properties();
        properties.load(new InputStreamReader(resource.getInputStream(), "UTF-8"));
        if (!properties.isEmpty()) {
            return new PropertiesPropertySource(name, properties);
        }
    }
    return null;
}