Choice of design pattern - serial execution

I have a simple design problem - I am looking for the best pattern to implement a simple functionality. Let's say, I am going to create an xml message in java. This message consists of many fields in different logic groups.

So, the first idea - create a class to set all fields. I can do it one method (which will be really long...) or split the method into multiple smaller (for each of the logical groups). However, I don't think it is a good approach, because the class will be really long and difficult to mantain.

The second idea is to create a functional interface and some implementations for different groups, for instance GroupXxxSetter, GroupYyySetter, etc. I can create and keep all instances in a list or a set and call the method defined inside the interface for each object stored inside the collection. It seems to be very similar to the 'Chain of responsibility' pattern. However, the idea of this pattern is different, so I am not sure if it is a good idea to use this pattern in my case.

Should I use the 'chain of responsibility' pattern here? Or, maybe there is something better?

Thanks in advance.