How to serialize B-tree java?

Question

Android

I implemented the Serializable interface and tried to write the entire tree to a file using the writeObject method on the ObjectOutputStream. The write succeeded, but the read failed with a java.lang.StackOverflowError

static class Node implements Serializable {
  char code;
  long frequency;
  boolean terminal;
  byte keyVal;
  LinkedList<Node> children;

  public Node() {
    this.frequency = 0;
    this.terminal = false;
    this.keyVal = 0;
    this.children = new LinkedList<Node>();
  }
}