如何在java中将协议缓冲区消息转换为HashMap？

<dependency>
    <groupId>com.google.protobuf</groupId>
    <artifactId>protobuf-java</artifactId>
    <version>3.18.0</version>
</dependency>

syntax = "proto3";

message MyMessage {
    string key = 1;
    int32 value = 2;
}

protoc --java_out=<output_directory> message.proto

import com.example.MyMessage; // 根据生成的Java类的包名导入

// 假设messageBytes是协议缓冲区消息的字节数组
MyMessage message = MyMessage.parseFrom(messageBytes);

// 将消息的字段值存储到HashMap中
HashMap<String, Object> hashMap = new HashMap<>();
hashMap.put("key", message.getKey());
hashMap.put("value", message.getValue());