Class1
Class2
Class3
Class4
etc.

"Class1", "Class3", "Class4"

if (myList.contains("Class1")) {
    Class1 object1 = new Class1(randomParams1);
    object1.method();
}
if (myList.contains("Class2")) {
    Class2 object2 = new Class2(randomParams2);
    object2.method();
}
if (myList.contains("Class3")) {
    Class3 object3 = new Class3(randomParams3);
    object3.method();
}
etc.