chat application cannot start about chat-application HOT 2 OPEN

i got this when i try to install chat plug-in for the first time
2016-10-16 21:27:15,900 | ERROR | Exception sending context initialized event to listener instance of class org.exoplatform.chat.listener.MigrateServiceListener [o.a.c.c.C.[.[localhost].[/chatServer]]
java.lang.UnsupportedOperationException: null
at java.util.Collections$UnmodifiableCollection.clear(Collections.java:1074) ~[na:1.8.0_102]
at org.exoplatform.chat.services.mongodb.MongoBootstrap.getDB(MongoBootstrap.java:126) ~[server-1.3.0.jar:1.3.0]
at org.exoplatform.chat.services.mongodb.MongoBootstrap.getDB(MongoBootstrap.java:112) ~[server-1.3.0.jar:1.3.0]
at org.exoplatform.chat.services.MigrateService.(MigrateService.java:22) ~[server-1.3.0.jar:1.3.0]
at org.exoplatform.chat.listener.MigrateServiceListener.contextInitialized(MigrateServiceListener.java:19) ~[server-1.3.0.jar:1.3.0]
at org.apache.catalina.core.StandardContext.listenerStart(StandardContext.java:5099) [catalina.jar:7.0.70]
at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5615) [catalina.jar:7.0.70]
at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:147) [catalina.jar:7.0.70]
at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:899) [catalina.jar:7.0.70]
at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:875) [catalina.jar:7.0.70]
at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:652) [catalina.jar:7.0.70]
at org.apache.catalina.startup.HostConfig.deployWAR(HostConfig.java:1092) [catalina.jar:7.0.70]
at org.apache.catalina.startup.HostConfig$DeployWar.run(HostConfig.java:1984) [catalina.jar:7.0.70]
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511) [na:1.8.0_102]
at java.util.concurrent.FutureTask.run(FutureTask.java:266) [na:1.8.0_102]
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142) [na:1.8.0_102]
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617) [na:1.8.0_102]
at java.lang.Thread.run(Thread.java:745) [na:1.8.0_102]

from chat-application.

ERROR | Exception sending context initialized event to listener instance of class org.exoplatform.chat.listener.MigrateServiceListener [o.a.c.c.C.[.[localhost].[/chatServer]]
java.lang.UnsupportedOperationException: null
at java.util.Collections$UnmodifiableCollection.clear(Collections.java:1074) ~[na:1.8.0_111]
at org.exoplatform.chat.services.mongodb.MongoBootstrap.getDB(MongoBootstrap.java:126) ~[server-1.3.0.jar:1.3.0]
at org.exoplatform.chat.services.mongodb.MongoBootstrap.getDB(MongoBootstrap.java:112) ~[server-1.3.0.jar:1.3.0]
at org.exoplatform.chat.services.MigrateService.(MigrateService.java:22) ~[server-1.3.0.jar:1.3.0]
at org.exoplatform.chat.listener.MigrateServiceListener.contextInitialized(MigrateServiceListener.java:19) ~[server-1.3.0.jar:1.3.0]
at org.apache.catalina.core.StandardContext.listenerStart(StandardContext.java:5099) [catalina.jar:7.0.70]
at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5615) [catalina.jar:7.0.70]
at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:147) [catalina.jar:7.0.70]
at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:899) [catalina.jar:7.0.70]
at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:875) [catalina.jar:7.0.70]
at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:652) [catalina.jar:7.0.70]
at org.apache.catalina.startup.HostConfig.deployWAR(HostConfig.java:1092) [catalina.jar:7.0.70]
at org.apache.catalina.startup.HostConfig$DeployWar.run(HostConfig.java:1984) [catalina.jar:7.0.70]
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511) [na:1.8.0_111]
at java.util.concurrent.FutureTask.run(FutureTask.java:266) [na:1.8.0_111]
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142) [na:1.8.0_111]
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617) [na:1.8.0_111]
at java.lang.Thread.run(Thread.java:745) [na:1.8.0_111]
2016-10-22 01:04:15,591 | ERROR | MongoDB Indexes couldn't be created during startup. Chat Extension may be unstable! [SchedulerService]
2016-10-22 01:04:15,591 | ERROR | One or more listeners failed to start. Full details will be found in the appropriate container log file [org.apache.catalina.core.StandardContext]
2016-10-22 01:04:15,592 | ERROR | Context [/chatServer] startup failed due to previous errors [org.apache.catalina.core.StandardContext]
2016-10-22 01:04:15,594 | INFO | CLOSING SCHEDULER [SchedulerManager]
2016-10-22 01:04:15,594 | INFO | Scheduler DefaultQuartzScheduler_$NON_CLUSTERED shutting down. [org.quartz.core.QuartzScheduler]
2016-10-22 01:04:15,594 | INFO | Scheduler DefaultQuartzScheduler$NON_CLUSTERED paused. [org.quartz.core.QuartzScheduler]
2016-10-22 01:04:15,594 | INFO | Scheduler DefaultQuartzScheduler$_NON_CLUSTERED shutdown complete. [org.quartz.core.QuartzScheduler]
2016-10-22 01:04:15,594 | INFO | CLOSING MONGODB [ConnectionManager]
2016-10-22 01:04:15,596 | INFO | CLOSING GUICE [GuiceManager]
2016-10-22 01:04:15,605 | ERROR | The web application [/chatServer] appears to have started a thread named [cluster-ClusterId{value='580a9eef330e7e0f0f300492', description='null'}-192.168.178.43:27017] but has failed to stop it. This is very likely to create a memory leak. [o.a.c.loader.WebappClassLoaderBase]
2016-10-22 01:04:15,605 | ERROR | The web application [/chatServer] appears to have started a thread named [pool-2-thread-1] but has failed to stop it. This is very likely to create a memory leak. [o.a.c.loader.WebappClassLoaderBase]
2016-10-22 01:04:15,606 | ERROR | The web application [/chatServer] appears to have started a thread named [DefaultQuartzScheduler_Worker-1] but has failed to stop it. This is very likely to create a memory leak. [o.a.c.loader.WebappClassLoaderBase]
2016-10-22 01:04:15,606 | ERROR | The web application [/chatServer] appears to have started a thread named [DefaultQuartzScheduler_Worker-2] but has failed to stop it. This is very likely to create a memory leak. [o.a.c.loader.WebappClassLoaderBase]
2016-10-22 01:04:15,606 | ERROR | The web application [/chatServer] appears to have started a thread named [DefaultQuartzScheduler_Worker-3] but has failed to stop it. This is very likely to create a memory leak. [o.a.c.loader.WebappClassLoaderBase]
2016-10-22 01:04:15,607 | ERROR | The web application [/chatServer] appears to have started a thread named [DefaultQuartzScheduler_Worker-4] but has failed to stop it. This is very likely to create a memory leak. [o.a.c.loader.WebappClassLoaderBase]
2016-10-22 01:04:15,607 | ERROR | The web application [/chatServer] appears to have started a thread named [DefaultQuartzScheduler_Worker-5] but has failed to stop it. This is very likely to create a memory leak. [o.a.c.loader.WebappClassLoaderBase]
2016-10-22 01:04:15,607 | ERROR | The web application [/chatServer] appears to have started a thread named [DefaultQuartzScheduler_Worker-6] but has failed to stop it. This is very likely to create a memory leak. [o.a.c.loader.WebappClassLoaderBase]
2016-10-22 01:04:15,608 | ERROR | The web application [/chatServer] appears to have started a thread named [DefaultQuartzScheduler_Worker-7] but has failed to stop it. This is very likely to create a memory leak. [o.a.c.loader.WebappClassLoaderBase]
2016-10-22 01:04:15,618 | ERROR | The web application [/chatServer] appears to have started a thread named [DefaultQuartzScheduler_Worker-8] but has failed to stop it. This is very likely to create a memory leak. [o.a.c.loader.WebappClassLoaderBase]
2016-10-22 01:04:15,619 | ERROR | The web application [/chatServer] appears to have started a thread named [DefaultQuartzScheduler_Worker-9] but has failed to stop it. This is very likely to create a memory leak. [o.a.c.loader.WebappClassLoaderBase]
2016-10-22 01:04:15,620 | ERROR | The web application [/chatServer] appears to have started a thread named [DefaultQuartzScheduler_Worker-10] but has failed to stop it. This is very likely to create a memory leak. [o.a.c.loader.WebappClassLoaderBase]
2016-10-22 01:04:15,621 | ERROR | The web application [/chatServer] appears to have started a thread named [cluster-ClusterId{value='580a9eef330e7e0f0f300493', description='null'}-192.168.178.43:27017] but has failed to stop it. This is very likely to create a memory leak. [o.a.c.loader.WebappClassLoaderBase]

from chat-application.