在java中存储哈夫曼树

import java.util.PriorityQueue;

class Node implements Comparable<Node> {
    char value;
    int frequency;
    Node leftChild;
    Node rightChild;

    public Node(char value, int frequency) {
        this.value = value;
        this.frequency = frequency;
    }

    @Override
    public int compareTo(Node other) {
        return this.frequency - other.frequency;
    }
}

public class HuffmanTree {
    private Node root;

    public HuffmanTree(String input) {
        buildTree(input);
    }

    private void buildTree(String input) {
        // 统计字符频率
        int[] frequencies = new int[256];
        for (char c : input.toCharArray()) {
            frequencies[c]++;
        }

        // 创建节点并加入优先队列
        PriorityQueue<Node> queue = new PriorityQueue<>();
        for (int i = 0; i < frequencies.length; i++) {
            if (frequencies[i] > 0) {
                queue.offer(new Node((char) i, frequencies[i]));
            }
        }

        // 构建哈夫曼树
        while (queue.size() > 1) {
            Node left = queue.poll();
            Node right = queue.poll();
            Node parent = new Node('\0', left.frequency + right.frequency);
            parent.leftChild = left;
            parent.rightChild = right;
            queue.offer(parent);
        }

        // 保存根节点
        root = queue.poll();
    }

    // 其他操作和方法...

    public static void main(String[] args) {
        String input = "Hello, World!";
        HuffmanTree tree = new HuffmanTree(input);
        // 其他操作和方法...
    }
}