final synchronized void unregisterMBean(final ObjectName on) {
// first check that on was registered using this instance
boolean removed = registeredObjectNames.remove(on);
- Preconditions.checkState(removed, "Cannot unregister - ObjectName not found in 'registeredObjectNames': {}", on);
+ Preconditions.checkState(removed, "Cannot unregister - ObjectName not found in 'registeredObjectNames': %s", on);
try {
getMBeanServer().unregisterMBean(on);