alibaba / alibaba/fastjson2

[BUG]fastjson反序列化又出现NoClassDefFoundError

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bug
Dominant language
Java
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Description

### 问题描述
```java
java.lang.NoClassDefFoundError: xxx/xxx/xxx/xxx/bean/response/BaseResponse$Error
at com.alibaba.fastjson2.reader.ORG_1_11_BaseResponse.readObject(Unknown Source)
at com.alibaba.fastjson2.JSON.parseObject(JSON.java:1534)
at com.xxx.xxx.xxx.xxx.JsonRpcUtils.decode(JsonRpcUtils.java:102)
at com.xxx.xxx.xxx.xxx.LspService.handleLspData(LspService.java:1364)
at com.xxx.xxx.xxx.xxx.LspService$3.onTextAvailable(LspService.java:1125)
at com.intellij.execution.process.ProcessHandler$2.onTextAvailable(ProcessHandler.java:289)
at com.intellij.execution.process.ProcessHandler.notifyTextAvailable(ProcessHandler.java:220)
at com.intellij.execution.process.BaseOSProcessHandler$SimpleOutputReader.onTextAvailable(BaseOSProcessHandler.java:133)
at com.intellij.util.io.BaseOutputReader.processInput(BaseOutputReader.java:213)
at com.intellij.util.io.BaseOutputReader.readAvailableBlocking(BaseOutputReader.java:151)
at com.intellij.util.io.BaseDataReader.readAvailable(BaseDataReader.java:72)
at com.intellij.util.io.BaseDataReader.doRun(BaseDataReader.java:153)
at com.intellij.util.ConcurrencyUtil.runUnderThreadName(ConcurrencyUtil.java:218)
at com.intellij.util.io.BaseDataReader.lambda$start$0(BaseDataReader.java:48)
at java.base/java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:539)
at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:264)
at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1136)
at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:635)
at java.base/java.util.concurrent.Executors$PrivilegedThreadFactory$1$1.run(Executors.java:702)
at java.base/java.util.concurrent.Executors$PrivilegedThreadFactory$1$1.run(Executors.java:699)
at java.base/java.security.AccessController.doPrivileged(AccessController.java:399)
at java.base/java.util.concurrent.Executors$PrivilegedThreadFactory$1.run(Executors.java:699)
at java.base/java.lang.Thread.run(Thread.java:840)
Caused by: java.lang.ClassNotFoundException: xxx.xxx.xxx.xxx.xxx.xxx.BaseResponse$Error
at java.base/java.lang.ClassLoader.findClass(ClassLoader.java:723)
at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:592)
at com.alibaba.fastjson2.util.DynamicClassLoader.loadClass(DynamicClassLoader.java:190)
at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:525)
... 23 more
```

### 环境信息
*请填写以下信息:*

- OS信息: windows 10
- JDK信息: JDK 17
- 版本信息:fastjson 2.0.57

### 重现步骤
问题场景同
https://github.com/alibaba/fastjson2/issues/3420
上一个issue调用的方法
```java
User user = Json.to(User.class, jsonStr);
```

现在出问题场景的调用方法是
```java
User user = JSON.parseObject(jsonStr, User.class);
```

问题完整复现场景:
User.Java
```java
package com.demo;

import com.alibaba.fastjson2.annotation.JSONField;

public class User {

@JSONField(name = "asss")
private String os;
private int age;
private Address address;

public String getOs() {
return os;
}

public void setOs(String name) {
this.os = name;
}

public int getAge() {
return age;
}

public void setAge(int age) {
this.age = age;
}

public Address getAddress() {
return address;
}

public void setAddress(Address address) {
this.address = address;
}

@Override
public String toString() {
return "User{" +
"name='" + os + '\'' +
", age=" + age +
", address=" + address +
'}';
}
}
```

Address.java
```java
package com.demo;

public class Address {

private String addr;

public String getAddr() {
return addr;
}

public void setAddr(String addr) {
this.addr = addr;
}

@Override
public String toString() {
return "Address{" +
"addr='" + addr + '\'' +
'}';
}
}
```

Example.java
```java
package com.demo;

import com.alibaba.fastjson2.JSON;
import com.alibaba.fastjson2.JSONObject;
import java.io.File;
import java.io.IOException;
import java.io.InputStream;
import java.nio.file.Files;
import java.nio.file.Paths;

public class Example {
public static void main(String[] args) throws ClassNotFoundException, IOException {
ExtClassLoader myClassLoader = new ExtClassLoader();
String jsonStr = "{\"name\": \"bobo\", \"age\": 15, \"address\": { \"addr\": \"demo address\" }}";
Class userClass = myClassLoader.loadClass("com.demo.User");

// 以下代码正常
// JSONObject jsonObject = JSONObject.parseObject(jsonStr);
// Object user = JSON.to(userClass, jsonObject);

Object user = JSON.parseObject(jsonStr, userClass); // 出错代码片段
System.out.println(user);
}

public static class ExtClassLoader
extends ClassLoader {
public ExtClassLoader() throws IOException {
}

@Override
public Class findClass(String name) throws ClassNotFoundException {
String path = "D:\\foo\\bar\\OtherModule"
+ File.separatorChar + name.replace('.', File.separatorChar) + ".class";
if (!Files.exists(Paths.get(path))) {
return super.findClass(name);
}
try {
byte[] bytes = Files.readAllBytes(Paths.get(path));
return defineClass(bytes, 0, bytes.length);
} catch (IOException e) {
e.printStackTrace();
throw new ClassNotFoundException();
}
}
}
}
```

### 期待的正确结果
可正常反序列化,不报错

### 相关日志输出
见前文问题描述

#### 附加信息
无附加信息

Contributor guide

Open the contributing guide

Research direction

Start with the provided Example.java reproduction and compare JSON.parseObject(jsonStr, userClass) with the working JSON.to path. Inspect the JSON.parseObject stack entry and DynamicClassLoader loading behavior; done means the supplied User and Address classes deserialize normally without NoClassDefFoundError.

Written by the indexing model from the issue text.

Assessment

Tech stack
java
Domain
backend
Issue type
Bug
Difficulty
4/5
Estimated time
3-5 days
Activity status
Stale
Clarity
Mostly clear
Newbie friendliness
35/100

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