You can put everything in a csv file, something like:
L1412,10,100,Nissan,Sedan
and create a static factory method to create the instance you want:
public static Vehical createVehical(String line){
String[] parts = line.split(",");
String type = parts[parts.length -1]; //get the last column
switch (type) {
case "Van":
return new Car(a, b, c,...);
case "Sedan":
return new Van(a, b, c...);
default:
return null;
}
}
For furture checking subclass, use
if(vehical instanceof Sedan){
}else if(vehical instanceof Van){
}else...
Or you can look into Java Generic Collections, it may help you to solve your problem, hope it helps