JSON.toJSONString() 序列化导致原Map的value转换为LinkedHashMap

[bzl132]

Describe the bug

JSON.toJSONString() 序列化导致原Map的value转换为LinkedHashMap。

Expected behavior

JSON.toJSONString() 序列化后不影响原实体

Actual behavior

JSON序列化自定义对象时，调用BeanSerializer.serialize()将对象转换成map

如果，自定义对象中属性是Map时，会将Value替换成递归调用的结果，

这时如果Value是对象，会转换成LinkedHashMap，返回后会替换原始实体

Steps to reproduce

运行Demo的main方法

Minimal yet complete reproducer code (or GitHub URL to code)

import com.alipay.sofa.rpc.common.json.JSON;
import java.util.HashMap;
import java.util.Map;

public class TestDemo {

public static void main(String[] args) {
    BeanEntity bean = new TestDemo.BeanEntity();
    Map<String, ? super ValueEntity> map = new HashMap<>();
    map.put("1", new ValueEntity());
    bean.map = map;

    String jsonString = JSON.toJSONString(bean);

    bean.map.values().forEach(value -> {
        System.out.println(value.getClass().getSimpleName());
    });
}

static class BeanEntity {
    Map<String, ? super ValueEntity> map;
}

static class ValueEntity {}

}

Environment

• SOFARPC version:5.7.3
• JVM version (e.g. java -version): 11.0.15
• OS version (e.g. uname -a): Windows10
• Maven version:3.6.1
• IDE version:idea 2020.2.4

[EvenLjj]

@bzl132 Thank you for feedback. It's really a bug, there should be a new map. Are you interested to fix it?

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[gofow]

Hi there, I'd like to take a crack at fixing it. Would you mind assigning the issue to me? My thought is to create a fresh Map within the serialize() function when the "bean" is a Map instance, in order to prevent any unpredictable changes due to references. @OrezzerO @EvenLjj

[EvenLjj]

@gofow You are right, looking forward to your participation.