将List <DerivedClass>转换为List <BaseClass>

import java.util.ArrayList;
import java.util.List;

class BaseClass {
}

class DerivedClass extends BaseClass {
}

public class Main {
    public static void main(String[] args) {
        List<DerivedClass> derivedClassList = new ArrayList<>();
        derivedClassList.add(new DerivedClass());
        derivedClassList.add(new DerivedClass());

        List<BaseClass> baseClassList = new ArrayList<>();
        for (DerivedClass derivedClass : derivedClassList) {
            baseClassList.add(derivedClass);
        }
    }
}