# Returns the JNI signature format of this Nit method
	#
	# Example: a Nity signature `(Bool, Int, Float, JavaString)` is represented by
	# the JNI format `(ZIDLjava/lang/string;)V"
	private fun build_jni_format(recv_mtype: MClassType, from_mmodule: MModule): String
	do
		var mmethoddef = lookup_first_definition(from_mmodule, recv_mtype)
		var msignature = mmethoddef.msignature
		var format = new Array[String]

		format.add "("

		# receiver
		if not self.is_init then format.add recv_mtype.jni_format

		# parameters
		for p in msignature.mparameters do
			var param_mtype = p.mtype.resolve_for(recv_mtype, recv_mtype, from_mmodule, true)
			format.add param_mtype.jni_format
		end
		format.add ")"

		# return
		if self.is_init then
			format.add recv_mtype.jni_format
		else
			var return_mtype = msignature.return_mtype
			if return_mtype != null then
				return_mtype = return_mtype.resolve_for(recv_mtype, recv_mtype, from_mmodule, true)
				format.add return_mtype.jni_format
			else format.add "V"
		end

		return format.join
	end