HTTP Api return Sever Error for stack command, InaccessibleObjectException: accessible: module java.base does not "opens java.lang" to unnamed module

[ayoubeddafali]

• I have searched the issues of this repository and believe that this is not a duplicate.

Environment

• Arthas version: 3.6.0
• Operating System version: Ubuntu 18.04
• Java version of target JVM: openjdk version 17
• Java version of JVM used to attach: openjdk version 17

Steps to reproduce this issue

1. attach arthas to a running jvm , and export 8563 port .
2. http api async_exec action with the following command "stack -n 1 *JsonSanitizer sanitizeString"

Expected Result

I expect to get the stack trace, like this one when running interactively :

Affect(class count: 1 , method count: 1) cost in 240 ms, listenerId: 21
Condition express: null , result: true
ts=2022-04-15 10:54:09;thread_name=http-nio-8080-exec-5;id=18;is_daemon=true;priority=5;TCCL=org.springframework.boot.web.embedded.tomcat.TomcatEmbeddedWebappClassLoader@180da663
    @com.google.json.JsonSanitizer.sanitizeString()
        at com.google.json.JsonSanitizer.sanitize(JsonSanitizer.java:237)
        at com.google.json.JsonSanitizer.sanitize(JsonSanitizer.java:122)
        at com.google.json.JsonSanitizer.sanitize(JsonSanitizer.java:109)

Actual Result

Server Error

If there is an exception, please attach the exception trace:

In arthas.log there is this exception

http request error: /api
com.alibaba.arthas.deps.com.alibaba.fastjson.JSONException: write javaBean error, fastjson version 1.2.75, class com.taobao.arthas.core.shell.term.impl.http.api.ApiResponse, write javaBean error, fastjson version 1.2.75, class com.taobao.arthas.core.command.model.StackModel, fieldName : 0, Unable to make field private java.lang.String java.lang.StackTraceElement.fileName accessible: module java.base does not "opens java.lang" to unnamed module @6145930e
	at com.alibaba.arthas.deps.com.alibaba.fastjson.serializer.JavaBeanSerializer.write(JavaBeanSerializer.java:539)
	at com.alibaba.arthas.deps.com.alibaba.fastjson.serializer.JavaBeanSerializer.write(JavaBeanSerializer.java:149)
	at com.alibaba.arthas.deps.com.alibaba.fastjson.serializer.JSONSerializer.write(JSONSerializer.java:312)
	at com.alibaba.arthas.deps.com.alibaba.fastjson.JSON.writeJSONString(JSON.java:1002)
	at com.alibaba.arthas.deps.com.alibaba.fastjson.JSON.writeJSONString(JSON.java:954)
	at com.alibaba.arthas.deps.com.alibaba.fastjson.JSON.writeJSONString(JSON.java:944)
	at com.taobao.arthas.core.shell.term.impl.http.api.HttpApiHandler.writeResult(HttpApiHandler.java:177)
	at com.taobao.arthas.core.shell.term.impl.http.api.HttpApiHandler.handle(HttpApiHandler.java:137)
	at com.taobao.arthas.core.shell.term.impl.http.HttpRequestHandler.channelRead0(HttpRequestHandler.java:80)
	at com.taobao.arthas.core.shell.term.impl.http.HttpRequestHandler.channelRead0(HttpRequestHandler.java:39)
	at com.alibaba.arthas.deps.io.netty.channel.SimpleChannelInboundHandler.channelRead(SimpleChannelInboundHandler.java:99)

[ayoubeddafali]

I couldn't reproduce the error when using java 8, so I am not sure if this is exclusive to version 17

[hengyunabc]

When using jdk 17, this JVM option --add-opens java.base/java.lang=ALL-UNNAMED is required in many scenarios.

The next version will try to fix the fastjson problem.

[ayoubeddafali]

@hengyunabc, Thank you so much.