Getting Exception when deploying portlet war file

[sandeep l，修改在7 年前。]

Hi ,
I am getting below exception when deploying Portlet war file. What could be the issue ? I am using Slf4j for logging.

20:49:49,114 INFO [org.jboss.web] (ServerService Thread Pool -- 129) JBAS018210: Register web context: /xyz-portlet
20:49:49,237 ERROR [stderr] (ServerService Thread Pool -- 129) java.lang.NullPointerException
20:49:49,238 ERROR [stderr] (ServerService Thread Pool -- 129) at com.liferay.util.log4j.Log4JUtil.configureLog4J(Log4JUtil.java:142)
20:49:49,238 ERROR [stderr] (ServerService Thread Pool -- 129) at com.liferay.portal.deploy.hot.PluginPackageHotDeployListener.initLogger(PluginPackageHotDeployListener.java:182)
20:49:49,239 ERROR [stderr] (ServerService Thread Pool -- 129) at com.liferay.portal.deploy.hot.PluginPackageHotDeployListener.doInvokeDeploy(PluginPackageHotDeployListener.java:130)
20:49:49,239 ERROR [stderr] (ServerService Thread Pool -- 129) at com.liferay.portal.deploy.hot.PluginPackageHotDeployListener.invokeDeploy(PluginPackageHotDeployListener.java:61)
20:49:49,239 ERROR [stderr] (ServerService Thread Pool -- 129) at com.liferay.portal.deploy.hot.HotDeployImpl.doFireDeployEvent(HotDeployImpl.java:230)
20:49:49,240 ERROR [stderr] (ServerService Thread Pool -- 129) at com.liferay.portal.deploy.hot.HotDeployImpl.fireDeployEvent(HotDeployImpl.java:96)
20:49:49,240 ERROR [stderr] (ServerService Thread Pool -- 129) at com.liferay.portal.kernel.deploy.hot.HotDeployUtil.fireDeployEvent(HotDeployUtil.java:28)
20:49:49,240 ERROR [stderr] (ServerService Thread Pool -- 129) at com.liferay.portal.kernel.servlet.PluginContextListener.fireDeployEvent(PluginContextListener.java:164)
20:49:49,241 ERROR [stderr] (ServerService Thread Pool -- 129) at com.liferay.portal.kernel.servlet.PluginContextListener.doPortalInit(PluginContextListener.java:154)
20:49:49,241 ERROR [stderr] (ServerService Thread Pool -- 129) at com.liferay.portal.kernel.util.BasePortalLifecycle.portalInit(BasePortalLifecycle.java:44)
20:49:49,241 ERROR [stderr] (ServerService Thread Pool -- 129) at com.liferay.portal.kernel.util.PortalLifecycleUtil.register(PortalLifecycleUtil.java:74)
20:49:49,242 ERROR [stderr] (ServerService Thread Pool -- 129) at com.liferay.portal.kernel.util.PortalLifecycleUtil.register(PortalLifecycleUtil.java:58)
20:49:49,242 ERROR [stderr] (ServerService Thread Pool -- 129) at com.liferay.portal.kernel.util.BasePortalLifecycle.registerPortalLifecycle(BasePortalLifecycle.java:54)
20:49:49,242 ERROR [stderr] (ServerService Thread Pool -- 129) at com.liferay.portal.kernel.servlet.PluginContextListener.contextInitialized(PluginContextListener.java:116)
20:49:49,243 ERROR [stderr] (ServerService Thread Pool -- 129) at com.liferay.portal.kernel.servlet.SecurePluginContextListener.contextInitialized(SecurePluginContextListener.java:151)
20:49:49,243 ERROR [stderr] (ServerService Thread Pool -- 129) at org.apache.catalina.core.StandardContext.contextListenerStart(StandardContext.java:3339)
20:49:49,243 ERROR [stderr] (ServerService Thread Pool -- 129) at org.apache.catalina.core.StandardContext.start(StandardContext.java:3780)
20:49:49,244 ERROR [stderr] (ServerService Thread Pool -- 129) at org.jboss.as.web.deployment.WebDeploymentService.doStart(WebDeploymentService.java:163)
20:49:49,244 ERROR [stderr] (ServerService Thread Pool -- 129) at org.jboss.as.web.deployment.WebDeploymentService.access$000(WebDeploymentService.java:61)
20:49:49,244 ERROR [stderr] (ServerService Thread Pool -- 129) at org.jboss.as.web.deployment.WebDeploymentService$1.run(WebDeploymentService.java:96)
20:49:49,245 ERROR [stderr] (ServerService Thread Pool -- 129) at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:471)
20:49:49,245 ERROR [stderr] (ServerService Thread Pool -- 129) at java.util.concurrent.FutureTask.run(FutureTask.java:262)
20:49:49,245 ERROR [stderr] (ServerService Thread Pool -- 129) at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
20:49:49,246 ERROR [stderr] (ServerService Thread Pool -- 129) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
20:49:49,246 ERROR [stderr] (ServerService Thread Pool -- 129) at java.lang.Thread.run(Thread.java:745)
20:49:49,246 ERROR [stderr] (ServerService Thread Pool -- 129) at org.jboss.threads.JBossThread.run(JBossThread.java:122)