How to write something like Haxe's typedef= in Java?

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1

How to write something like Haxe’s typedef in Java instead of class ?

2

Java has primitive types, objects and arrays and that’s it. No typedefs.

Source: Is there a Java equivalent or methodology for the typedef keyword in C++? - Stack Overflow

3

MessagePack from Haxe to Java problem

I just use Haxe’s lib MessagePack to encode from Haxe’s typedef to Java Native

but Java native don’t know how to decode Haxe’s typedef,because Java have no [typedef]

but haxe can decode from Java Native encode data,

are there any easy way to fixed that ?