Linux下Matlab R2020A启动log4j缺失报错的解决办法

问题描述 #

我在Linux系统上启动Matlab R2020A时出现以下错误。公司因安全问题移除了log4j，请问该错误是否有影响？若有影响，我有哪些解决选项？

错误日志 #

Exception in thread "CFB Source Control Executor": java.lang.NoClassDefFoundError: org/apache/log4j/Appender
at java.lang.Class.forName0(Native Method)
at java.lang.Class.forName(Class.java:264)
at com.mathworks.util.ImplementorsCacheImpl.getService(ImplementorsCacheImpl.java:142)
at com.mathworks.util.ImplementorsCacheImpl.getServicesForImplementors(ImplementorsCacheImpl.java:126)
at com.mathworks.util.ImplementorsCacheImpl.getImplementors(ImplementorsCacheImpl.java:61)
at com.mathworks.cmlink.management.registration.OsgiCMAdapterFactoryList.lookUpFactories(OsgiCMAdapterFactoryList.java:35)
at com.mathworks.cmlink.management.registration.OsgiCMAdapterFactoryList.<init>(OsgiCMAdapterFactoryList.java:27)
at com.mathworks.cmlink.management.registration.OsgiCMAdapterFactoryList.<clinit>(OsgiCMAdapterFactoryList.java:17)
at com.mathworks.cmlink.management.registration.SingletonCMAdapterFactoryList.getCMAdapterFactoryLists(SingletonCMAdapterFactoryList.java:32)
at com.mathworks.cmlink.management.registration.SingletonCMAdapterFactoryList.<clinit>(SingletonCMAdapterFactoryList.java:14)
at com.mathworks.cmlink.management.pool.adapter.PrefBackedAdapterFactoryProvider.provide(PrefBackedAdapterFactoryProvider.java:29)
at com.mathworks.cmlink.util.adapter.CMAdapterFactoryProviderDecorator.provide(CMAdapterFactoryProviderDecorator.java:19)
at com.mathworks.cmlink.util.adapter.transformer.TransformableCMAdapterFactoryProvider.provide(TransformableCMAdapterFactoryProvider.java:24)
at com.mathworks.cmlink.util.adapter.CMAdapterFactoryProviderDecorator.provide(CMAdapterFactoryProviderDecorator.java:19)
at com.mathworks.cmlink.util.adapter.transformer.TransformableCMAdapterFactoryProvider.provide(TransformableCMAdapterFactoryProvider.java:24)
at com.mathworks.cmlink.management.pool.PooledCmStatusCacheEntry.<init>(PooledCmStatusCacheEntry.java:77)
at com.mathworks.cmlink.management.pool.PooledCmStatusCacheProvider$1.<init>(PooledCmStatusCacheProvider.java:101)
at com.mathworks.cmlink.management.pool.PooledCmStatusCacheProvider.provideEntryFor(PooledCmStatusCacheProvider.java:98)
at com.mathworks.cmlink.management.pool.PooledCmStatusCacheProvider.provideCacheUnsafe(PooledCmStatusCacheProvider.java:55)
at com.mathworks.cmlink.management.pool.PooledCmStatusCacheProvider.provideCacheFor(PooledCmStatusCacheProvider.java:47)
at com.mathworks.cmlink.management.cache.RootSearchingCmStatusCacheFactory.provideCacheFor(RootSearchingCmStatusCacheFactory.java:38)
at com.mathworks.sourcecontrol.SCAdapterConnectionManager.updateCache(SCAdapterConnectionManager.java:174)
at com.mathworks.sourcecontrol.SCAdapterConnectionManager.access$500(SCAdapterConnectionManager.java:29)
at com.mathworks.sourcecontrol.SCAdapterConnectionManager$2.run(SCAdapterConnectionManager.java:78)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
at java.lang.Thread.run(Thread.java:748)
Caused by: java.lang.ClassNotFoundException: org.apache.log4j.Appender
    at java.net.URLClassLoader.findClass(URLClassLoader.java:381)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
    at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:349)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
    ... 27 more
Exception in thread "CFB Source Control Executor": java.lang.NoClassDefFoundError: Could not initialize class com.mathworks.cmlink.management.registration.SingletonCMAdapterFactoryList
    at com.mathworks.cmlink.management.pool.adapter.PrefBackedAdapterFactoryProvider.provide(PrefBackedAdapterFactoryProvider.java:29)
    at com.mathworks.cmlink.util.adapter.CMAdapterFactoryProviderDecorator.provide(CMAdapterFactoryProviderDecorator.java:19)
    at com.mathworks.cmlink.util.adapter.transformer.TransformableCMAdapterFactoryProvider.provide(TransformableCMAdapterFactoryProvider.java:24)
    at com.mathworks.cmlink.util.adapter.CMAdapterFactoryProviderDecorator.provide(CMAdapterFactoryProviderDecorator.java:19)
    at com.mathworks.cmlink.util.adapter.transformer.TransformableCMAdapterFactoryProvider.provide(TransformableCMAdapterFactoryProvider.java:24)
    at com.mathworks.cmlink.management.pool.PooledCmStatusCacheEntry.<init>(PooledCmStatusCacheEntry.java:77)
    at com.mathworks.cmlink.management.pool.PooledCmStatusCacheProvider$1.<init>(PooledCmStatusCacheProvider.java:101)
    at com.mathworks.cmlink.management.pool.PooledCmStatusCacheProvider.provideEntryFor(PooledCmStatusCacheProvider.java:98)
    at com.mathworks.cmlink.management.pool.PooledCmStatusCacheProvider.provideCacheUnsafe(PooledCmStatusCacheProvider.java:55)
    at com.mathworks.cmlink.management.pool.PooledCmStatusCacheProvider.provideCacheFor(PooledCmStatusCacheProvider.java:47)
    at com.mathworks.cmlink.management.cache.RootSearchingCmStatusCacheFactory.provideCacheFor(RootSearchingCmStatusCacheFactory.java:38)
    at com.mathworks.sourcecontrol.SCAdapterConnectionManager.updateCache(SCAdapterConnectionManager.java:174)
    at com.mathworks.sourcecontrol.SCAdapterConnectionManager.access$500(SCAdapterConnectionManager.java:29)
    at com.mathworks.sourcecontrol.SCAdapterConnectionManager$2.run(SCAdapterConnectionManager.java:78)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
    at java.lang.Thread.run(Thread.java:748)

错误影响分析 #

从报错栈可以看出，缺失的org.apache.log4j.Appender类是Matlab源代码控制（Source Control）模块依赖的组件。这个错误只会影响Matlab的源代码控制功能：

• 无法使用Matlab内置的源代码管理集成（比如连接Git、SVN等版本控制系统）
• 源代码状态缓存更新失败，可能导致文件状态显示异常
• Matlab主程序核心功能（计算、脚本编辑、工具箱使用等）不会受影响，依然可以正常运行

解决选项 #

选项1：替换为安全版本的log4j #

向公司安全部门申请符合安全要求的log4j 1.x安全补丁版本（比如log4j 1.2.17的安全修复版），将对应的log4j.jar文件放到Matlab的Java类路径中：

• 找到Matlab的Java库目录，通常在$MATLAB_ROOT/java/jar/toolbox下（$MATLAB_ROOT是Matlab安装路径，比如/usr/local/MATLAB/R2020a）
• 将安全版的log4j.jar复制到该目录，或者添加到Matlab的Java类路径配置中
• 重启Matlab即可恢复源代码控制功能

选项2：禁用Matlab的源代码控制模块 #

如果不需要使用Matlab的源代码控制集成，可以直接禁用该模块，避免报错：

1. 启动Matlab时添加参数跳过源代码控制初始化：

   matlab -nojvm
   

   注意：-nojvm会禁用所有Java相关功能，除了源代码控制，还会影响GUI界面、部分工具箱，适合仅用命令行的场景
2. 或者修改Matlab配置文件，禁用源代码控制服务：
   • 编辑Matlab启动目录下的startup.m文件，添加以下代码：

     com.mathworks.sourcecontrol.SCAdapterConnectionManager.disable;
     

   • 重启Matlab，源代码控制模块会被禁用，报错不再出现

选项3：升级Matlab版本 #

Matlab R2020a是较旧的版本，后续版本（比如R2021b及以后）已经替换或移除了对log4j 1.x的依赖，升级到新版本可以从根本上解决这个问题。需要确认公司是否允许升级，以及新版本是否兼容现有工作流程。

内容的提问来源于stack exchange，提问作者Mastiff