2018-05-31 07:20:36,766 | DEBUG | 237)-10.110.3.30 | call                             |  -  -  | RMI TCP Connection(237)-1.1.1.1: [1.1.1.1] exception: 
javax.management.RuntimeMBeanException: java.lang.NullPointerException
	at com.sun.jmx.interceptor.DefaultMBeanServerInterceptor.rethrow(DefaultMBeanServerInterceptor.java:839)[:1.8.0_161]
	at com.sun.jmx.interceptor.DefaultMBeanServerInterceptor.rethrowMaybeMBeanException(DefaultMBeanServerInterceptor.java:852)[:1.8.0_161]
	at com.sun.jmx.interceptor.DefaultMBeanServerInterceptor.invoke(DefaultMBeanServerInterceptor.java:821)[:1.8.0_161]
	at com.sun.jmx.mbeanserver.JmxMBeanServer.invoke(JmxMBeanServer.java:801)[:1.8.0_161]
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)[:1.8.0_161]
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)[:1.8.0_161]
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)[:1.8.0_161]
	at java.lang.reflect.Method.invoke(Method.java:498)[:1.8.0_161]
	at org.apache.karaf.management.internal.MBeanInvocationHandler.invoke(MBeanInvocationHandler.java:60)[46:org.apache.karaf.management.server:2.4.0.redhat-621216]
	at com.sun.proxy.$Proxy2.invoke(Unknown Source)[:]
	at javax.management.remote.rmi.RMIConnectionImpl.doOperation(RMIConnectionImpl.java:1468)
	at javax.management.remote.rmi.RMIConnectionImpl.access$300(RMIConnectionImpl.java:76)
	at javax.management.remote.rmi.RMIConnectionImpl$PrivilegedOperation.run(RMIConnectionImpl.java:1309)
	at java.security.AccessController.doPrivileged(Native Method)[:1.8.0_161]
	at javax.management.remote.rmi.RMIConnectionImpl.doPrivilegedOperation(RMIConnectionImpl.java:1408)
	at javax.management.remote.rmi.RMIConnectionImpl.invoke(RMIConnectionImpl.java:829)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)[:1.8.0_161]
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)[:1.8.0_161]
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)[:1.8.0_161]
	at java.lang.reflect.Method.invoke(Method.java:498)[:1.8.0_161]
	at sun.rmi.server.UnicastServerRef.dispatch(UnicastServerRef.java:361)[:1.8.0_161]
	at sun.rmi.transport.Transport$1.run(Transport.java:200)[:1.8.0_161]
	at sun.rmi.transport.Transport$1.run(Transport.java:197)[:1.8.0_161]
	at java.security.AccessController.doPrivileged(Native Method)[:1.8.0_161]
	at sun.rmi.transport.Transport.serviceCall(Transport.java:196)[:1.8.0_161]
	at sun.rmi.transport.tcp.TCPTransport.handleMessages(TCPTransport.java:568)[:1.8.0_161]
	at sun.rmi.transport.tcp.TCPTransport$ConnectionHandler.run0(TCPTransport.java:826)[:1.8.0_161]
	at sun.rmi.transport.tcp.TCPTransport$ConnectionHandler.lambda$run$0(TCPTransport.java:683)[:1.8.0_161]
	at java.security.AccessController.doPrivileged(Native Method)[:1.8.0_161]
	at sun.rmi.transport.tcp.TCPTransport$ConnectionHandler.run(TCPTransport.java:682)[:1.8.0_161]
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)[:1.8.0_161]
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)[:1.8.0_161]
	at java.lang.Thread.run(Thread.java:748)[:1.8.0_161]
Caused by: java.lang.NullPointerException
	at java.io.Writer.write(Writer.java:157)[:1.8.0_161]
	at org.apache.felix.utils.properties.Properties$PropertiesWriter.writeProperty(Properties.java:1098)
	at org.apache.felix.utils.properties.Properties.saveLayout(Properties.java:480)
	at org.apache.felix.utils.properties.Properties.save(Properties.java:165)
	at org.apache.felix.utils.properties.Properties.save(Properties.java:161)
	at org.apache.felix.utils.properties.Properties.store(Properties.java:177)
	at org.apache.karaf.util.properties.FileLockUtils$2.call(FileLockUtils.java:106)
	at org.apache.karaf.util.properties.FileLockUtils.execute(FileLockUtils.java:69)
	at org.apache.karaf.util.properties.FileLockUtils.execute(FileLockUtils.java:97)
	at org.apache.karaf.admin.internal.AdminServiceImpl.execute(AdminServiceImpl.java:210)
	at org.apache.karaf.admin.internal.AdminServiceImpl.createInstance(AdminServiceImpl.java:236)
	at Proxyc6694036_20fc_41cd_bc3f_ef641b6dbeaf.createInstance(Unknown Source)
	at org.apache.karaf.admin.management.internal.AdminServiceMBeanImpl.createInstance(AdminServiceMBeanImpl.java:77)
	at org.apache.karaf.admin.management.internal.AdminServiceMBeanImpl.createInstance(AdminServiceMBeanImpl.java:62)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)[:1.8.0_161]
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)[:1.8.0_161]
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)[:1.8.0_161]
	at java.lang.reflect.Method.invoke(Method.java:498)[:1.8.0_161]
	at sun.reflect.misc.Trampoline.invoke(MethodUtil.java:71)[:1.8.0_161]
	at sun.reflect.GeneratedMethodAccessor21.invoke(Unknown Source)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)[:1.8.0_161]
	at java.lang.reflect.Method.invoke(Method.java:498)[:1.8.0_161]
	at sun.reflect.misc.MethodUtil.invoke(MethodUtil.java:275)[:1.8.0_161]
	at com.sun.jmx.mbeanserver.StandardMBeanIntrospector.invokeM2(StandardMBeanIntrospector.java:112)[:1.8.0_161]
	at com.sun.jmx.mbeanserver.StandardMBeanIntrospector.invokeM2(StandardMBeanIntrospector.java:46)[:1.8.0_161]
	at com.sun.jmx.mbeanserver.MBeanIntrospector.invokeM(MBeanIntrospector.java:237)[:1.8.0_161]
	at com.sun.jmx.mbeanserver.PerInterface.invoke(PerInterface.java:138)[:1.8.0_161]
	at com.sun.jmx.mbeanserver.MBeanSupport.invoke(MBeanSupport.java:252)[:1.8.0_161]
	at javax.management.StandardMBean.invoke(StandardMBean.java:405)[:1.8.0_161]
	at com.sun.jmx.interceptor.DefaultMBeanServerInterceptor.invoke(DefaultMBeanServerInterceptor.java:819)[:1.8.0_161]
	... 30 more