我想通过反射取到TreeMap中的root字段然后遍历这颗树

Question

取到root字段后不会转换成Map.Entry类型了

import java.lang.reflect.Field;
import java.util.TreeMap;

public class Main {
    public static final Object PRESENT = new Object();
    public static void main(String[] args) throws Exception {
        TreeMap<Integer, Object> tree = new TreeMap<Integer, Object>();
        tree.put(1, PRESENT);
        Class<? extends TreeMap> c = tree.getClass();
        Field root = c.getDeclaredField("root");
        root.setAccessible(true);
        System.out.println(root.getType());
    }
}