java io.NotSerializableException when removing showcase-portlet from liferay 6.2:
An exception was seen after removing the showcase-portlet folder from the webapps directory while the server was running.
Note** the tooltip component was added to the portlet page during the session.
{code}
INFO: Undeploying context [/showcase-portlet]
Jun 07, 2016 7:31:51 PM org.apache.catalina.session.StandardSession writeObject
WARNING: Cannot serialize session attribute org.icefaces.impl.application.Window
ScopeManager for session A0FE592AFDEECAA85A295B6D303D5EB2
java.io.NotSerializableException: org.icefaces.ace.component.tooltip.Tooltip
        at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1183)

        at java.io.ObjectOutputStream.defaultWriteFields(ObjectOutputStream.java
:1547)
        at java.io.ObjectOutputStream.writeSerialData(ObjectOutputStream.java:15
08)
        at java.io.ObjectOutputStream.writeOrdinaryObject(ObjectOutputStream.jav
a:1431)
        at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1177)

        at java.io.ObjectOutputStream.writeObject(ObjectOutputStream.java:347)
        at java.util.HashMap.writeObject(HashMap.java:1133)
        at sun.reflect.GeneratedMethodAccessor875.invoke(Unknown Source)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAcces
sorImpl.java:43)
        at java.lang.reflect.Method.invoke(Method.java:606)
        at java.io.ObjectStreamClass.invokeWriteObject(ObjectStreamClass.java:98
8)
        at java.io.ObjectOutputStream.writeSerialData(ObjectOutputStream.java:14
95)
        at java.io.ObjectOutputStream.writeOrdinaryObject(ObjectOutputStream.jav
a:1431)
        at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1177)

        at java.io.ObjectOutputStream.writeObject(ObjectOutputStream.java:347)
        at java.util.HashMap.writeObject(HashMap.java:1133)
        at sun.reflect.GeneratedMethodAccessor875.invoke(Unknown Source)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAcces
sorImpl.java:43)
        at java.lang.reflect.Method.invoke(Method.java:606)
        at java.io.ObjectStreamClass.invokeWriteObject(ObjectStreamClass.java:98
8)
        at java.io.ObjectOutputStream.writeSerialData(ObjectOutputStream.java:14
95)
        at java.io.ObjectOutputStream.writeOrdinaryObject(ObjectOutputStream.jav
a:1431)
        at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1177)

        at java.io.ObjectOutputStream.writeObject(ObjectOutputStream.java:347)
        at org.icefaces.impl.application.WindowScopeManager$State.writeExternal(
WindowScopeManager.java:539)
        at java.io.ObjectOutputStream.writeExternalData(ObjectOutputStream.java:
1458)
        at java.io.ObjectOutputStream.writeOrdinaryObject(ObjectOutputStream.jav
a:1429)
        at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1177)

        at java.io.ObjectOutputStream.writeObject(ObjectOutputStream.java:347)
        at org.apache.catalina.session.StandardSession.writeObject(StandardSessi
on.java:1695)
        at org.apache.catalina.session.StandardSession.writeObjectData(StandardS
ession.java:1101)
        at org.apache.catalina.session.StandardManager.doUnload(StandardManager.
java:430)
        at org.apache.catalina.session.StandardManager.unload(StandardManager.ja
va:351)
        at org.apache.catalina.session.StandardManager.stopInternal(StandardMana
ger.java:516)
        at org.apache.catalina.util.LifecycleBase.stop(LifecycleBase.java:232)
        at org.apache.catalina.core.StandardContext.stopInternal(StandardContext
.java:5719)
        at org.apache.catalina.util.LifecycleBase.stop(LifecycleBase.java:232)
        at org.apache.catalina.core.ContainerBase.removeChild(ContainerBase.java
:1028)
        at org.apache.catalina.startup.HostConfig.undeploy(HostConfig.java:1547)

        at org.apache.catalina.startup.HostConfig.checkResources(HostConfig.java
:1474)
        at org.apache.catalina.startup.HostConfig.check(HostConfig.java:1695)
        at org.apache.catalina.startup.HostConfig.lifecycleEvent(HostConfig.java
:333)
        at org.apache.catalina.util.LifecycleSupport.fireLifecycleEvent(Lifecycl
eSupport.java:117)
        at org.apache.catalina.util.LifecycleBase.fireLifecycleEvent(LifecycleBa
se.java:90)
        at org.apache.catalina.core.ContainerBase.backgroundProcess(ContainerBas
e.java:1374)
        at org.apache.catalina.core.ContainerBase$ContainerBackgroundProcessor.p
rocessChildren(ContainerBase.java:1546)
        at org.apache.catalina.core.ContainerBase$ContainerBackgroundProcessor.p
rocessChildren(ContainerBase.java:1556)
        at org.apache.catalina.core.ContainerBase$ContainerBackgroundProcessor.r
un(ContainerBase.java:1524)
        at java.lang.Thread.run(Thread.java:745)

19:31:51,432 INFO [ContainerBackgroundProcessor[StandardEngine[Catalina]]][HotD
eployEvent:145] Plugin showcase-portlet requires marketplace-portlet
19:31:51,532 INFO [ContainerBackgroundProcessor[StandardEngine[Catalina]]][Port
letHotDeployListener:525] Unregistering portlets for showcase-portlet
19:31:51,582 INFO [ContainerBackgroundProcessor[StandardEngine[Catalina]]][Port
letHotDeployListener:565] 179 portlets for showcase-portlet were unregistered
Jun 07, 2016 7:31:51 PM org.apache.catalina.core.ApplicationContext log
INFO: Closing Spring root WebApplicationContext
19:31:51,582 INFO [ContainerBackgroundProcessor[StandardEngine[Catalina]]][Plug
inPackageUtil:1016] Reading plugin package for showcase-portlet
Jun 07, 2016 7:31:53 PM org.apache.catalina.loader.WebappClassLoader checkThread
LocalMapForLeaks
SEVERE: The web application [/showcase-portlet] created a ThreadLocal with key o
f type [org.icefaces.ace.context.RequestContext$1] (value [org.icefaces.ace.cont
ext.RequestContext$1@590c14ff]) and a value of type [org.icefaces.ace.context.De
faultRequestContext] (value [org.icefaces.ace.context.DefaultRequestContext@2836
9f05]) but failed to remove it when the web application was stopped. Threads are
 going to be renewed over time to try and avoid a probable memory leak.
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