Get fields for super class

 
import java.lang.reflect.Field;
import java.util.Collection;
import java.util.HashMap;
import java.util.Map;

public class Main {
    public static Collection<Field> getFields(Class<?> clazz) {
        Map<String, Field> fields = new HashMap<String, Field>();
        while (clazz != null) {
            for (Field field : clazz.getDeclaredFields()) {
                if (!fields.containsKey(field.getName())) {
                    fields.put(field.getName(), field);
                }
            }

            clazz = clazz.getSuperclass();
        }

        Collection<Field> returnCollection = fields.values();
        return returnCollection;
    }

}