question: public static boolean checkPoolPropertiesChanged ( Set < String > existingValue , Set < String > newValue ) { boolean propertyChanged = false ; if ( existingValue == null && ( newValue != null && ! newValue . isEmpty ( ) ) ) { propertyChanged = true ; } else if ( newValue == null && ( existingValue != null && ! existingValue . isEmpty ( ) ) ) { propertyChanged = true ; } else if ( existingValue != null && newValue != null ) { if ( existingValue . size ( ) != newValue . size ( ) || ! ( existingValue . containsAll ( newValue ) ) ) { propertyChanged = true ; } } return propertyChanged ; }
target:  compares the two given Sets. Caller is using this to check whether a pool property has changed.