javax/management/MBeanServer加载程序约束违规问题

Question

我试图将应用程序从JBoss-4.0.4.GA迁移到wildfly-10.1.0.Final。我遇到了JMX的问题。

在应用程序的启动时，我发现了以下内容：

10:58:02,689 WARN [org.jboss.modules] (ServerService Thread Pool -- 90) Failed to define class javax.management.MBeanServer in Module "com.xor.genesis:main" from local module loader @1c2c22f3 (finder: local module finder @18e8568 (roots: /home/user/wildfly-10.1.0.Final/modules,/home/user/wildfly-10.1.0.Final/modules/system/layers/base)): java.lang.LinkageError: Failed to link javax/management/MBeanServer (Module "com.xor.genesis:main" from local module loader @1c2c22f3 (finder: local module finder @18e8568 (roots: /home/chaos1/wildfly-10.1.0.Final/modules,/home/chaos1/wildfly-10.1.0.Final/modules/system/layers/base))): loader constraint violation: loader (instance of org/jboss/modules/ModuleClassLoader) previously initiated loading for a different type with name "javax/management/MBeanServer" 
    at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) 
    at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62) 
    at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45) 
    at java.lang.reflect.Constructor.newInstance(Constructor.java:423) 
    at org.jboss.modules.ModuleClassLoader.defineClass(ModuleClassLoader.java:446) 
    at org.jboss.modules.ModuleClassLoader.loadClassLocal(ModuleClassLoader.java:274) 
    at org.jboss.modules.ModuleClassLoader$1.loadClassLocal(ModuleClassLoader.java:78) 
    at org.jboss.modules.Module.loadModuleClass(Module.java:606) 
    at org.jboss.modules.ModuleClassLoader.findClass(ModuleClassLoader.java:190) 
    at org.jboss.modules.ConcurrentClassLoader.performLoadClassUnchecked(ConcurrentClassLoader.java:363) 
    at org.jboss.modules.ConcurrentClassLoader.performLoadClass(ConcurrentClassLoader.java:351) 
    at org.jboss.modules.ConcurrentClassLoader.loadClass(ConcurrentClassLoader.java:93) 
    at com.xor.genesis.core.jmx.framework.ApplicationMBeanManager.registerMBean(ApplicationMBeanManager.java:37) 
    at com.xor.genesis.cgo.listeners.CGOApplicationListener.registerApplicationLogger(CGOApplicationListener.java:161) 
    at com.xor.genesis.cgo.listeners.CGOApplicationListener.initMBeans(CGOApplicationListener.java:112) 
    at com.xor.genesis.cgo.listeners.CGOApplicationListener.contextInitialized(CGOApplicationListener.java:59) 
    at io.undertow.servlet.core.ApplicationListeners.contextInitialized(ApplicationListeners.java:187) 
    at io.undertow.servlet.core.DeploymentManagerImpl$1.call(DeploymentManagerImpl.java:200) 
    at io.undertow.servlet.core.DeploymentManagerImpl$1.call(DeploymentManagerImpl.java:171) 
    at io.undertow.servlet.core.ServletRequestContextThreadSetupAction$1.call(ServletRequestContextThreadSetupAction.java:42) 
    at io.undertow.servlet.core.ContextClassLoaderSetupAction$1.call(ContextClassLoaderSetupAction.java:43) 
    at io.undertow.servlet.api.LegacyThreadSetupActionWrapper$1.call(LegacyThreadSetupActionWrapper.java:44) 
    at io.undertow.servlet.api.LegacyThreadSetupActionWrapper$1.call(LegacyThreadSetupActionWrapper.java:44) 
    at io.undertow.servlet.api.LegacyThreadSetupActionWrapper$1.call(LegacyThreadSetupActionWrapper.java:44) 
    at io.undertow.servlet.api.LegacyThreadSetupActionWrapper$1.call(LegacyThreadSetupActionWrapper.java:44) 
    at io.undertow.servlet.api.LegacyThreadSetupActionWrapper$1.call(LegacyThreadSetupActionWrapper.java:44) 
    at io.undertow.servlet.core.DeploymentManagerImpl.deploy(DeploymentManagerImpl.java:234) 
    at org.wildfly.extension.undertow.deployment.UndertowDeploymentService.startContext(UndertowDeploymentService.java:100) 
    at org.wildfly.extension.undertow.deployment.UndertowDeploymentService$1.run(UndertowDeploymentService.java:82) 
    at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511) 
    at java.util.concurrent.FutureTask.run(FutureTask.java:266) 
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142) 
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617) 
    at java.lang.Thread.run(Thread.java:748) 
    at org.jboss.threads.JBossThread.run(JBossThread.java:320) 

要在代码级更精确的下面的行是生产上述异常：

MBeanServer server = java.lang.management.ManagementFactory.getPlatformMBeanServer(); 

我创建自己的模块与所需的罐子清单。我没有修改野蝇内的客户端库。

你有什么想法可以解决这个问题吗？

感谢， 阿纳托利

Answer 1

这是错误消息的有趣的部分：

装载机约束冲突：装载机（的 组织/ JBoss的/模块实例/ ModuleClassLoader）先前启动加载的 不同类型的名称为“javax/management/MBeanServer”

潜在问题解释为here更详细。本文的结论是：

在简单的话，可能会出现链接错误，如果两个不同的类 彼此互动，并在此互动类是指 类型具有相同的符号名称但不同的类的对象。

不同的类对象来源于类通过不同的类加载器加载的事实，因为每个类都由它的FQN和（！）加载它的类加载器来标识。

请检查您的类路径中是否存在javax/management/MBeanServer的多个实例（位于Wildfly/JBoss的模块目录中，甚至在您的部署中）。