java - 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 ? ? ü ? problem

In this class I have the representation of the custom attributes.

@Component
@ConfigurationProperties(prefix="custom.mail.property")
public class MailProperties {
    private String subjectMessage;
    public String getSubjectMessage() {
        return subjectMessage;
    }
    public void setSubjectMessage(String subjectMessage) {
        this.subjectMessage = subjectMessage;
    }

And here I use my MailProperties:

@Service
public class SimpleUnknownResponseMessage extends MailProperties implements UnknownResponseMessage{

    private JavaMailSender javaMailSender;

    @Autowired
    public SimpleUnknownResponseMessage(JavaMailSender javaMailSender) {
        this.javaMailSender = javaMailSender;
    }

    @Override
    public void placeUnknownResponse(BookResponse bookResponse) {
        MimeMessage message = javaMailSender.createMimeMessage();
        try {
            MimeMessageHelper helper = new MimeMessageHelper(message, "UTF-8");
            helper.setSubject(this.getSubjectMessage());            
            javaMailSender.send(message);

        } catch (MessagingException e) {
            e.printStackTrace();
        }
    }

While debugging I can see that my this.getSubjectMessage() variable has this value inside: This is a ?¤ ?? ?? ? problem. So before sending my mail I already have an UTF-8 encoding problem.

I already checked the encoding of the application.properties file and its UTF-8.

My IDE(STS/Eclipse) and the project properties are also set on UTF-8.

How can I set the UTF-8 encoding for the text of my custom attributes in the application.properties file?

Answer 1

As already mentioned in the comments .properties files are expected to be encoded in ISO 8859-1. One can use unicode escapes to specify other characters. There is also a tool available to do the conversion. This can for instance be used in the automatic build so that you still can use your favorite encoding in the source.