Please check this post: Making your Java code null-safe without rewriting

Things can get confusing if the explanation is too long, so here’s a concise way to put it.

It’s not entirely clear whether Groovy includes 100% of Java syntax, but in my view, Groovy focuses on enhancing the language itself, addressing areas where it falls short compared to modern languages.

On the other hand, JPlus is similar to how TypeScript addresses JavaScript’s lack of type safety: it focuses on strengthening Java’s safety while improving developer convenience through features like boilerplate code generation. Importantly, JPlus code always compiles down to standard Java, which means it can be integrated seamlessly into existing Java projects without changing the build environment or toolchain.

In short:

Groovy: Focuses on enhancing the expressive power of Java, adding modern language features and syntactic flexibility.

JPlus: Focuses on enhancing language safety and developer convenience, while maintaining full compatibility with Java. This allows developers to adopt JPlus without worrying about breaking existing Java projects.