How to store the Alloy solution into a desired Data structure?

How to store the Alloy solution into a desired Data structure?

I built an Alloy model and it successfully enumerated all the solutions I
want. Each solution is a A4Solution object.
The output of each instance should be a simple Java POJO object, like the
example below:
Class POJO {
int a;
int b;
String c;
boolean d;
}
My Alloy model basically generated all the possible combinations of the
above 4 fields.
My question is that the A4Solution object is very complicated, how can I
parse the object and store the generated fields into the POJO above?
Thanks