toString() can be implemented on Java types to return a human-readable textual representation useful for debugging, but should it also be used to return a portable string suitable for serialization and persistence?

I was experimenting with building a container image for my Spring Boot application (Spring Boot version 3.5.7, Java version 25). And I was wondering which approach would be better: use the Maven plugin with spring-boot:build-image to build the image, or use a custom Dockerfile with jlink.

For such a widely used piece of data like a URI, surely we must have water tight specifications right?

According to RFC 3986: Uniform Resource Identifier (URI) (2005) + is a reserved character which, if not used as a delimiter, must be percent-encoded as %2B.