Wan-Derer

class Main {
    public static void main(String[] args) {
        A b = Fabric.getInstance("B");
        A c = Fabric.getInstance("C");

        System.out.println(b.getString());
        System.out.println(c.getString());
    }

}

class Fabric {

    public static A getInstance(String className) {
        return switch (className) {
            case "B" -> new B();
            case "C" -> new C();
            default -> throw new IllegalArgumentException("Unknown class name " + className);
        };
    }
}

interface A {
    String getString();
}

class B implements A {
    @Override
    public String getString() {
        return "bbb";
    }
}

class C implements A {
    @Override
    public String getString() {
        return "ccc";
    }
}

$get_params = drupal_get_query_parameters();
echo $get_params['arg'];

@Query(value = "select FIELD1, FIELD2 from TABLE
where
      CRITERIA1 = :criteria1 and
      CRITERIA2 = :criteria2 and
      CRITERIA3 in :criteria3 and
      CRITERIA4 in :criteria4", native = true);

List<MyPOJO> getAllPojo(@Param Integer criteria1, @Param String criteria2, @Param List<Integer> criteria3, @Param List<String> criteria4);

-- get records with wrong parents
select * 
from test
where 
	parent_id is not null 
	and not exists (
		select id from test as parents where parents.id = test.parent_id
	);
	
-- delete records with wrong parents
delete test.* 
from test
left join test as parents on parents.id = test.parent_id
where test.parent_id is not null and parents.id is null;

select * from test;

-- add foreign key to prevent missing parents
alter table test add foreign key (parent_id) references test(id);