https://www.ibm.com/support/pages/apar/IV98401
IV98401: JAVA.NET.URLCLASSLOADER.CLOSE() METHOD DOESNOT RELEASE THE JAR FILES IT OPENED.
Error Message: Unable to delete jar file being used by java.net.URLClassLaoder even after calling close() on it.
https://www.ibm.com/support/pages/apar/IV98370
IV98370: PERFORMANCE DEGRADATION WHILE LOADING CLASSES USING JAVA.NET.URLCLASSLOADER AFTER...
Error Message: Performance degradation after migrating to Java 7 and above.
using javaperformancedegradationloading