我有一个嵌入felix osgi容器的java应用程序。 java应用程序使用log4j 2.8.2。
我的一个osgi实现包也使用log4j。因此，我将罐子log4j-api-2.8.2和log4j-core-2.8.2添加到osgi系统中：
bundleContext.installBundle()
用以下内容启动捆绑包：
bundle.start()
安装捆绑包工作正常。除了bundle“org.apache.felix.scr”的启动之外引发异常：
ERROR StatusLogger Unable to create custom ContextSelector. Falling back to default.
java.lang.ClassCastException: Cannot cast org.apache.logging.log4j.core.osgi.BundleContextSelector to
org.apache.logging.log4j.core.selector.ContextSelector
我怀疑这是因为felix SCR正在尝试加载我正在使用log4j的实现包。因为我的应用程序（嵌入felix的应用程序）使用log4j并且可能使用ContextSelector。 osgi可能使用BundleContextSelector。因此例外。
我想知道我该如何解决这个问题？
我已经尝试将我的应用程序的ContextSelector设置为osgi one：
System.setProperty("Log4jContextSelector",
"org.apache.logging.log4j.core.osgi.BundleContextSelector")
但那里没有运气。我也尝试产生一个新的线程来设置osgi / felix。我的想法已经不多了。
我目前已从log4j切换到我的应用程序的java util日志记录。我的实现osgi bundle可以这样使用log4j而没有问题。
仅供参考，这是完整的异常跟踪：
ERROR StatusLogger Unable to create custom ContextSelector. Falling back to default.
java.lang.ClassCastException: Cannot cast org.apache.logging.log4j.core.osgi.BundleContextSelector to org.apache.logging.log4j.core.selector.ContextSelector
at java.lang.Class.cast(Class.java:3369)
at org.apache.logging.log4j.util.LoaderUtil.newCheckedInstanceOf(LoaderUtil.java:201)
at org.apache.logging.log4j.util.LoaderUtil.newCheckedInstanceOfProperty(LoaderUtil.java:226)
at org.apache.logging.log4j.core.impl.Log4jContextFactory.createContextSelector(Log4jContextFactory.java:97)
at org.apache.logging.log4j.core.impl.Log4jContextFactory.<init>(Log4jContextFactory.java:58)
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 java.lang.Class.newInstance(Class.java:442)
at org.apache.logging.log4j.LogManager.<clinit>(LogManager.java:94)
at com.okwant.emap.impl.ui.UIImpl.<clinit>(UIImpl.java:18)
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 java.lang.Class.newInstance(Class.java:442)
at org.apache.felix.scr.impl.manager.SingleComponentManager.createImplementationObject(SingleComponentManager.java:237)
at org.apache.felix.scr.impl.manager.SingleComponentManager.createComponent(SingleComponentManager.java:109)
at org.apache.felix.scr.impl.manager.SingleComponentManager.getService(SingleComponentManager.java:906)
at org.apache.felix.scr.impl.manager.SingleComponentManager.getServiceInternal(SingleComponentManager.java:879)
at org.apache.felix.scr.impl.manager.AbstractComponentManager.activateInternal(AbstractComponentManager.java:749)
at org.apache.felix.scr.impl.manager.AbstractComponentManager.enableInternal(AbstractComponentManager.java:675)
at org.apache.felix.scr.impl.manager.AbstractComponentManager.enable(AbstractComponentManager.java:430)
at org.apache.felix.scr.impl.manager.ConfigurableComponentHolder.enableComponents(ConfigurableComponentHolder.java:657)
at org.apache.felix.scr.impl.BundleComponentActivator.initialEnable(BundleComponentActivator.java:341)
at org.apache.felix.scr.impl.Activator.loadComponents(Activator.java:390)
at org.apache.felix.scr.impl.Activator.access$200(Activator.java:54)
at org.apache.felix.scr.impl.Activator$ScrExtension.start(Activator.java:265)
at org.apache.felix.utils.extender.AbstractExtender.createExtension(AbstractExtender.java:254)
at org.apache.felix.utils.extender.AbstractExtender.modifiedBundle(AbstractExtender.java:227)
at org.apache.felix.utils.extender.AbstractExtender.addingBundle(AbstractExtender.java:187)
at org.osgi.util.tracker.BundleTracker$Tracked.customizerAdding(BundleTracker.java:469)
at org.osgi.util.tracker.BundleTracker$Tracked.customizerAdding(BundleTracker.java:415)
at org.osgi.util.tracker.AbstractTracked.trackAdding(AbstractTracked.java:256)
at org.osgi.util.tracker.AbstractTracked.trackInitial(AbstractTracked.java:183)
at org.osgi.util.tracker.BundleTracker.open(BundleTracker.java:156)
at org.apache.felix.utils.extender.AbstractExtender.startTracking(AbstractExtender.java:150)
at org.apache.felix.utils.extender.AbstractExtender.doStart(AbstractExtender.java:142)
at org.apache.felix.scr.impl.Activator.doStart(Activator.java:172)
at org.apache.felix.utils.extender.AbstractExtender.start(AbstractExtender.java:114)
at org.apache.felix.scr.impl.Activator.restart(Activator.java:142)
at org.apache.felix.scr.impl.config.ScrConfigurationImpl.configure(ScrConfigurationImpl.java:196)
at org.apache.felix.scr.impl.config.ScrConfigurationImpl.start(ScrConfigurationImpl.java:117)
at org.apache.felix.scr.impl.Activator.start(Activator.java:110)
at org.apache.felix.framework.util.SecureAction.startActivator(SecureAction.java:697)
at org.apache.felix.framework.Felix.activateBundle(Felix.java:2238)
at org.apache.felix.framework.Felix.startBundle(Felix.java:2144)
at org.apache.felix.framework.BundleImpl.start(BundleImpl.java:998)
at org.apache.felix.framework.BundleImpl.start(BundleImpl.java:984)
at com.okwant.emap.client.HostActivator.installAndStartSystemBundles(HostActivator.java:82)
at com.okwant.emap.client.HostActivator.start(HostActivator.java:37)
at org.apache.felix.framework.util.SecureAction.startActivator(SecureAction.java:697)
at org.apache.felix.framework.Felix$SystemBundleActivator.start(Felix.java:4860)
at org.apache.felix.framework.util.SecureAction.startActivator(SecureAction.java:697)
at org.apache.felix.framework.Felix.init(Felix.java:844)
at org.apache.felix.framework.Felix.init(Felix.java:625)
at org.apache.felix.framework.Felix.start(Felix.java:963)
at com.okwant.emap.client.ClientOsgi.setupOsgi(ClientOsgi.java:55)
at com.okwant.emap.client.ClientFrame.doInit(ClientFrame.java:30)
at com.okwant.emap.client.ClientApp.<init>(ClientApp.java:21)
at com.okwant.emap.client.ClientApp.main(ClientApp.java:43)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
at com.intellij.rt.execution.application.AppMain.main(AppMain.java:147)
ERROR StatusLogger Unable to create custom ContextSelector. Falling back to default.
java.lang.ClassCastException: Cannot cast org.apache.logging.log4j.core.osgi.BundleContextSelector to org.apache.logging.log4j.core.selector.ContextSelector
at java.lang.Class.cast(Class.java:3369)
at org.apache.logging.log4j.util.LoaderUtil.newCheckedInstanceOf(LoaderUtil.java:201)
at org.apache.logging.log4j.util.LoaderUtil.newCheckedInstanceOfProperty(LoaderUtil.java:226)
at org.apache.logging.log4j.core.impl.Log4jContextFactory.createContextSelector(Log4jContextFactory.java:97)
at org.apache.logging.log4j.core.impl.Log4jContextFactory.<init>(Log4jContextFactory.java:58)
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 java.lang.Class.newInstance(Class.java:442)
at org.apache.logging.log4j.LogManager.<clinit>(LogManager.java:94)
at com.okwant.emap.impl.ui.UIImpl.<clinit>(UIImpl.java:18)
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 java.lang.Class.newInstance(Class.java:442)
at org.apache.felix.scr.impl.manager.SingleComponentManager.createImplementationObject(SingleComponentManager.java:237)
at org.apache.felix.scr.impl.manager.SingleComponentManager.createComponent(SingleComponentManager.java:109)
at org.apache.felix.scr.impl.manager.SingleComponentManager.getService(SingleComponentManager.java:906)
at org.apache.felix.scr.impl.manager.SingleComponentManager.getServiceInternal(SingleComponentManager.java:879)
at org.apache.felix.scr.impl.manager.AbstractComponentManager.activateInternal(AbstractComponentManager.java:749)
at org.apache.felix.scr.impl.manager.AbstractComponentManager.enableInternal(AbstractComponentManager.java:675)
at org.apache.felix.scr.impl.manager.AbstractComponentManager.enable(AbstractComponentManager.java:430)
at org.apache.felix.scr.impl.manager.ConfigurableComponentHolder.enableComponents(ConfigurableComponentHolder.java:657)
at org.apache.felix.scr.impl.BundleComponentActivator.initialEnable(BundleComponentActivator.java:341)
at org.apache.felix.scr.impl.Activator.loadComponents(Activator.java:390)
at org.apache.felix.scr.impl.Activator.access$200(Activator.java:54)
at org.apache.felix.scr.impl.Activator$ScrExtension.start(Activator.java:265)
at org.apache.felix.utils.extender.AbstractExtender.createExtension(AbstractExtender.java:254)
at org.apache.felix.utils.extender.AbstractExtender.modifiedBundle(AbstractExtender.java:227)
at org.apache.felix.utils.extender.AbstractExtender.addingBundle(AbstractExtender.java:187)
at org.osgi.util.tracker.BundleTracker$Tracked.customizerAdding(BundleTracker.java:469)
at org.osgi.util.tracker.BundleTracker$Tracked.customizerAdding(BundleTracker.java:415)
at org.osgi.util.tracker.AbstractTracked.trackAdding(AbstractTracked.java:256)
at org.osgi.util.tracker.AbstractTracked.trackInitial(AbstractTracked.java:183)
at org.osgi.util.tracker.BundleTracker.open(BundleTracker.java:156)
at org.apache.felix.utils.extender.AbstractExtender.startTracking(AbstractExtender.java:150)
at org.apache.felix.utils.extender.AbstractExtender.doStart(AbstractExtender.java:142)
at org.apache.felix.scr.impl.Activator.doStart(Activator.java:172)
at org.apache.felix.utils.extender.AbstractExtender.start(AbstractExtender.java:114)
at org.apache.felix.scr.impl.Activator.restart(Activator.java:142)
at org.apache.felix.scr.impl.config.ScrConfigurationImpl.configure(ScrConfigurationImpl.java:196)
at org.apache.felix.scr.impl.config.ScrConfigurationImpl.start(ScrConfigurationImpl.java:117)
at org.apache.felix.scr.impl.Activator.start(Activator.java:110)
at org.apache.felix.framework.util.SecureAction.startActivator(SecureAction.java:697)
at org.apache.felix.framework.Felix.activateBundle(Felix.java:2238)
at org.apache.felix.framework.Felix.startBundle(Felix.java:2144)
at org.apache.felix.framework.BundleImpl.start(BundleImpl.java:998)
at org.apache.felix.framework.BundleImpl.start(BundleImpl.java:984)
at com.okwant.emap.client.HostActivator.installAndStartSystemBundles(HostActivator.java:82)
at com.okwant.emap.client.HostActivator.start(HostActivator.java:37)
at org.apache.felix.framework.util.SecureAction.startActivator(SecureAction.java:697)
at org.apache.felix.framework.Felix$SystemBundleActivator.start(Felix.java:4860)
at org.apache.felix.framework.util.SecureAction.startActivator(SecureAction.java:697)
at org.apache.felix.framework.Felix.init(Felix.java:844)
at org.apache.felix.framework.Felix.init(Felix.java:625)
at org.apache.felix.framework.Felix.start(Felix.java:963)
at com.okwant.emap.client.ClientOsgi.setupOsgi(ClientOsgi.java:55)
at com.okwant.emap.client.ClientFrame.doInit(ClientFrame.java:30)
at com.okwant.emap.client.ClientApp.<init>(ClientApp.java:21)
at com.okwant.emap.client.ClientApp.main(ClientApp.java:43)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
答案 0 :(得分：0)
我设法通过以下方式实现了类似的目标
： ClassLoader contextClassLoader =
Thread.currentThread().getContextClassLoader();
Logger mine;
LoggerContext loggerContext;
try {
Thread.currentThread().setContextClassLoader(Foo.class.getClassLoader());
loggerContext = (LoggerContext) LogManager.getContext(null,
true, new File("log4j2_2.xml").toURI());
mine = loggerContext.getLogger("internal");
} finally {
if (contextClassLoader != null) {
Thread.currentThread().setContextClassLoader(contextClassLoader);
}
}