[WICKET-4955] SessionData violates comparison contract

• Type: Bug
• Status: Resolved
• Priority: Minor
• Resolution: Fixed
• Affects Version/s: 6.4.0
• Fix Version/s: 6.5.0
• Labels: requestlogger
• Environment: java 7
• Assignee: Emond Papegaaij
• Reporter: Sverre Boschman
• Created: 08/Jan/13 08:11
• Updated: 10/Jan/13 09:49
• Resolved: 08/Jan/13 19:06

Description

AbstractRequestLogger.getLiveSessions sorts the SessionData objects, this sort 'sometimes' (most likely load/concurrency) results in a contract violation:

Caused by: org.apache.wicket.WicketRuntimeException: Error calling method: public final java.lang.Integer org.apache.wicket.proxy.$Proxy200.getLiveSessions() on object: org.apache.wicket.proxy.LazyInitProxyFactory$JdkHandler@438532d0
at org.apache.wicket.core.util.lang.PropertyResolver$MethodGetAndSet.getValue(PropertyResolver.java:1148)
at org.apache.wicket.core.util.lang.PropertyResolver$ObjectAndGetSetter.getValue(PropertyResolver.java:649)
at org.apache.wicket.core.util.lang.PropertyResolver.getValue(PropertyResolver.java:103)
at org.apache.wicket.model.AbstractPropertyModel.getObject(AbstractPropertyModel.java:86)
at org.apache.wicket.Component.getDefaultModelObject(Component.java:1615)
... 75 more
Caused by: java.lang.IllegalArgumentException: Comparison method violates its general contract!
at java.util.ComparableTimSort.mergeHi(ComparableTimSort.java:835)
at java.util.ComparableTimSort.mergeAt(ComparableTimSort.java:453)
at java.util.ComparableTimSort.mergeForceCollapse(ComparableTimSort.java:392)
at java.util.ComparableTimSort.sort(ComparableTimSort.java:191)
at java.util.ComparableTimSort.sort(ComparableTimSort.java:146)
at java.util.Arrays.sort(Arrays.java:472)
at org.apache.wicket.protocol.http.AbstractRequestLogger.getLiveSessions(AbstractRequestLogger.java:135)
at nl.topicus.cobra.monitoring.BaseApplicationInfo.getLiveSessions(BaseApplicationInfo.java:103)
at sun.reflect.GeneratedMethodAccessor256.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:601)
at org.apache.wicket.proxy.LazyInitProxyFactory$JdkHandler.invoke(LazyInitProxyFactory.java:434)
at org.apache.wicket.proxy.$Proxy200.getLiveSessions(Unknown Source)
at sun.reflect.GeneratedMethodAccessor255.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:601)
at org.apache.wicket.core.util.lang.PropertyResolver$MethodGetAndSet.getValue(PropertyResolver.java:1144)
... 79 more