reflection fails to access a private nested class

 
try {
abortTimeoutTask =
Class.forName(conf.get(ABORT_TIMEOUT_TASK, SystemExitWhenAbortTimeout.class.getName()))
.asSubclass(TimerTask.class).getDeclaredConstructor().newInstance();
} catch (Exception e) {
LOG.warn("Initialize abort timeout task failed", e);
}

2019-08-16 18:01:40,737 [WARN ] HRegionServer:1046 Initialize abort timeout task failed
 java.lang.IllegalAccessException: Class org.apache.hadoop.hbase.regionserver.HRegionServer can not access a member of class org.apache.hadoop.hbase.regionss
 erver.HRegionServer$SystemExitWhenAbortTimeout with modifiers "private"
 at sun.reflect.Reflection.ensureMemberAccess(Reflection.java:102)
 at java.lang.reflect.AccessibleObject.slowCheckMemberAccess(AccessibleObject.java:296)
 at java.lang.reflect.AccessibleObject.checkAccess(AccessibleObject.java:288)
 at java.lang.reflect.Constructor.newInstance(Constructor.java:413)
 at org.apache.hadoop.hbase.regionserver.HRegionServer.run(HRegionServer.java:1044)
 at org.apache.hadoop.hbase.master.HMaster.run(HMaster.java:598)